JVC HDV Camera and Lens Options

[David Jinks]

Regarding the JVC GY-HD100 and it's lens options.

Having seen the camera and decks at a number of trade shows recently.
People do not seem to realise that the HD100 does not have a record-in facility.

This comes with the GY-HD101 which could be released a couple of months later.

The standard 16x lens has a Fuginon designator of 6t - where the 't' stands for "third" of an inch.
The additional 13x lens is denoted by 13h - the 'h' being for HD - apparently.
The price of the additional lens has been quoted at between £4K-5.5 - ouch !
NB. There has previously been some e-noise regarding the suitability of the standard offering for HD(V).
Apparently, these 1/2" lenses have been around before - anyone know where ?
There was some rumour about the 16x lens being part of that range and not originally developed for the higher resolutions required by this new format...?

Considering that the HDV tape transport mechnism could be transitory and the JVC deck is £2,500 and together with all of the issues with HDV1 and HDV2 etc. it may be better to spend the extra money on the improved lens. Hopefully, it will not turn out to be this expensive on release.

And yes, the camera has 1/4" screw mount for the standard tripod plate and therefore doesn't require the ubiquitous release plate at an extra £100 or so.

It'll be interesting to see all of this pan out.
Will Canon release something soon, if so, will it be of this quality or more like JVC's earlier HD-10 style ?

Either way, it appears a better offering than the consumer derived Z1 and the costly and (as yet) vapour-ware DVX200.
Time will tell ...

Apparently, the second HD-100 that came across for their road shows did work, but died soon afterwards. The JVC backroom Johnnies seemed to know why. Obviously, pre-productionn teething troubles. Pity though.

Good to see this news board tying up with Showreel magazine and much better than the rubbish often spouted on US sites.
Computer Video lives on - Great stuff !

Regards,

David Jinks.

[infocus]

Some interesting snippets! I was wondering about the cost of the wider angle lens - I wonder how much a package would be with it, but without the 16x? I suspect we're now getting into sums of money considerably more than a Z1, which perhaps just goes to show there's no such thing as a free lunch.

My trust in JVC was shaken by their marketing of the PD1, and was just beginning to come back with the HD100. If it appears the 16x lens is an SD lens, that's not good - I've heard that an SD lens on an HD camera is a bad thing, apparently the HD shows up the imperfections in a way an SD camera masks. To sell an HD camera with an SD lens as a package doesn't inspire confidence. And to sell a non input enabled camera like this without a clear warning is unforgiveable.

Yes, the question is what can we expect from Canon?

[jayess]

David,

The JVC US site has been updated and the 16x lens is now referred to as Th16x5.5BRMU in the updated specifications and accessories areas.

Note the h for HD designation has appeared.

Jonathan

[David Jinks]

Although the lens options make the HD100 a lot more expensive than the HDR-Z1 I think the differences are significant to warrant a cost difference in this region. However, £5.5K would be taking the urine somewhat.

JVC has stated that they would consider selling it body-only on a pick 'n' mix basis.

The fact that the HD-100 is not record-inable is being passed off as an EU restriction when probed. It didn't wash with me to be honest. JVC's shiny new HD50 deck bears this out in my opinion. I thought that this restriction was catapulted out of existence some time back (DSR PD-150 etc.)

I've also noticed that JVC seems to have stopped demo'ing the camera with a battery - perhaps to prevent people trying to switch it on.

The comprehensive US .pdf brochure not only itemises the option list, but also displays them also. The 13x WA lens is quite a bit longer than the standard 16x model.

I can see another reason for purchasing a IDX house brick...

DLE - HDD (Firestore FS Pro)
=====================

It seems the DLE HDD records the same MPEG-2 stream as it does to tape.
Pity it doesn't record a 1280x720 .AVI in a similar format to Cineform Aspect HD and thus circumventing the MPEG-2 issues and drawbacks. Perhaps it could - anyone know ?

With HDD's getting larger and cheaper by the day it would be almost ideal.

1080i vs 720p - resolution
===================

It's been stated on this and other sites that 1080i has greater resolution when compared to 720p. From my understanding the 1080 lines over 720 is outweighed by the fact that only half of the lines are displayed at any one time (ie. interlaced). Whereas all 720 lines are displayed at once in the 720p format. I make this better (540/720) ! I'd be glad to be corrected by those more knowledgable on the matter.

1080i vx 720p - application
====================

It's also been stated that 720p is better for sport and 1080i for drama-based productions. I understand this to be the reverse. In the US I thought 1080i was being adopted specifically for sport applications - possibly due to fast pans etc ? Similarly, by the Sports cable channels.

Interesting times.

Regards,

David Jinks.

[infocus]

It's been stated on this and other sites that 1080i has greater resolution when compared to 720p. From my understanding the 1080 lines over 720 is outweighed by the fact that only half of the lines are displayed at any one time (ie. interlaced). Whereas all 720 lines are displayed at once in the 720p format. I make this better (540/720) ! I'd be glad to be corrected by those more knowledgable on the matter.

I think that's a cue for Mr Roberts and the Kell factor...... ;)

Having said which, would it be a good idea to sticky a FAQ of Alans technical explanations of matters like this to the top of this forum? Could save a lot of future typing when questions like this come up in the future!

[StevenBagley]

It seems the DLE HDD records the same MPEG-2 stream as it does to tape.
Pity it doesn't record a 1280x720 .AVI in a similar format to Cineform Aspect HD and thus circumventing the MPEG-2 issues and drawbacks. Perhaps it could - anyone know ?


No chance without significant modifications to the camera which would need to supply uncompressed HD out on to an external encoder chip.

It's been stated on this and other sites that 1080i has greater resolution when compared to 720p. From my understanding the 1080 lines over 720 is outweighed by the fact that only half of the lines are displayed at any one time (ie. interlaced). Whereas all 720 lines are displayed at once in the 720p format. I make this better (540/720) ! I'd be glad to be corrected by those more knowledgable on the matter.


This *might* have been true on CRT based displays (all though we SD displays can certainly get more than 288 lines displayed from a PAL signal) but as most HD capable displays are pixel mapped it doesn't apply. A typical plasma or LCD (with 1280x720 panel) will refresh every 1/50s every pixel on the panel whether being fed 720p50 or 1080i25. If fed 1080i25, then the panel obviously has to scale this to the panel res which means deinterlacing it to 1080p50 at some point. Depending on how this deinterlacing is done you should find that you fill the panel with as much if not more resolution from a 1080i signal as you do from a 720p one.

And as displays move to being 1080p native then 1080i means you are capturing more res to display. Of course, this assumes that the camera can capture that much res in the first place, that the tape format doesn't decimate the high frequencies (DVCProHD capture as 960x720, the severity of MPEG compression in Hdv will do nasties to the image too) and I doubt that the lens on the Z1 or the JVC are really up to the job. It is worth remembering that the cost of the JVC camera is about half the cost of a professional HD lens...

It's also been stated that 720p is better for sport and 1080i for drama-based productions. I understand this to be the reverse. In the US I thought 1080i was being adopted specifically for sport applications - possibly due to fast pans etc ? Similarly, by the Sports cable channels.

720p50/60 should give better results than 1080i at the same field rate because it refreshes every line every refresh rather than alternate ones so you don't get combing effects like you can with interlace. However, Sky's own tests over here suggest people prefer the look of 1080i over 720p for sport so don't always trust the science!

For drama, especially if you are going for 24fps/25fps motion than 720p never makes sense as you are always delivering less pixels than if you shoot and distribute 1080p25 as 25psf.

Of course it is worth remembering that the JVC HD cameras are useless as they crippled to a 25fps frame rate. In other words, you get jerky-motion whether you want it or not. Presumably the JVC camera does let you select a 1/50s shutter -- if not then it is not even suitable for drama acquisition.

Steven

[jayess]

I am currently working on an independent feature film shot 25p on HDCAM

There is no nasty jerkiness, it looks like film.

If you want live TV look get a Z1, want film look get a HD100.

[StevenBagley]

I am currently working on an independent feature film shot 25p on HDCAM

There is no nasty jerkiness, it looks like film.

Exactly -- film jerks :)

If you want live TV look get a Z1, want film look get a HD100.

But different jobs may require different looks, or the same job may require different looks in different scenes. The HD100 is crippled in that it can only provide film-like looks, whereas the Z1 can provide both (native interlace -- conversion to film-like look is a pretty mature technology now). I'm fully aware of technologies to get from film-look to video-look, as used on several BBC programmes, but the fact remains they take far longer to process than adding a film-look and add in their own motion oddities (they look like standards conversions if you are not careful). It is always better to start with more information and decimate down in my opinion.

If you can afford multiple cameras then get both, but if you are after just one, the hd100 is inherently flawed from the start.

Steven

[infocus]

.......... the hd100 is inherently flawed from the start.

I know exactly what you're saying, and don't really disagree with it. But it is important to define perspective, and whilst your comment may be true from an engineering aspect, from a cameramans perspective it's the Z1 that is inherently flawed - not technically, but in terms of usability. As has been said many times before, it is a very high quality consumer camera.

All of which is why there is so much interest awaiting what Canon are going to do. Let's just hope it's more like the the Z1s innards in an HD100 body than the HD100s innards in a Z1 body....... ;)

[StevenBagley]

I know exactly what you're saying, and don't really disagree with it. But it is important to define perspective, and whilst your comment may be true from an engineering aspect, from a cameramans perspective it's the Z1 that is inherently flawed - not technically, but in terms of usability. As has been said many times before, it is a very high quality consumer camera.

Well I was speaking as much from an artistic point of view as an engineering POV. With the Z1 (albeit in a cumbersome manner) I can obtain video-look and film-look material (either natively, or via any number of software or hardware devices). With the JVC, I'm forced into film-look. (Yes, I could process it up to a video look but it'd take well over a day to do a 30min doc, in HD res). The result I've lost artistic choices compared to the Z1.

And here is an interesting question -- which will look better technically? Progressive 1280x720 @25fps from the hd100 or the 1080i Z1 footage given a film-like look and downscaled to 720p. (In other words, will the artefacts from the Z1's mpeg encoding be filtered off in the downconversion?)

All of which is why there is so much interest awaiting what Canon are going to do. Let's just hope it's more like the the Z1s innards in an HD100 body than the HD100s innards in a Z1 body....... ;)

I'm far more interested in when the cheap pro HD cameras arrive from the likes of Sony -- i.e. the equivalent to the DSR-500/570/450 (almost certainly XDCam based) as that is the market segment which we are missing at the moment. WE have the HDV models, in the PD150 end of the market. The F900, F750, F730 in the Digibeta end of the pro market -- it's the bit in the middle we are missing -- the bit that is needed if the BBC is going to take its output HD to film shows like 'Trading Up'.

Steven

[infocus]

Well I was speaking as much from an artistic point of view as an engineering POV. .............

..........I'm far more interested in when the cheap pro HD cameras arrive from the likes of Sony -- i.e. the equivalent to the DSR-500/570/450 (almost certainly XDCam based) as that is the market segment which we are missing at the moment. WE have the HDV models, in the PD150 end of the market. The F900, F750, F730 in the Digibeta end of the pro market -- it's the bit in the middle we are missing -- the bit that is needed if the BBC is going to take its output HD to film shows like 'Trading Up'.

Fair point, I'm not arguing about which will "look" better, or whether that's an artistic or engineering criteria, rather which I would prefer to operate on a day by day basis. (Only seeing a small v/f image after all. ;) ) The HD100 is styled and has it's pedigree in pro cameras operationally, but yes, it's lacking in other ways as you say. Hence the interest in Canons intentions, for the prosumer market at least.

As for your comments about cheap pro HD cameras, then yes, absolutely. An "HD DSR570" must be what that market's ready for. That and down the scale true consumer HD, by which I mean small and light enough to take on holiday.

[StevenBagley]

The HD100 is styled and has it's pedigree in pro cameras operationally, but yes, it's lacking in other ways as you say.

Oh I won't argue that the JVC is styled and operates the right way, but it also seems about as flawed as producing a camera that is only black and white to me. :)

Hence the interest in Canons intentions, for the prosumer market at least.

I just hope it gives better pictures than the XL1, which always seem too edgy and with odd colourimetry from what I've seen

That and down the scale true consumer HD, by which I mean small and light enough to take on holiday.

Indeed, I'm very interested in the HC1/A1 for just that reason.

Steven
(fed up with carting a VX1000 on planes)

[cstv]

That and down the scale true consumer HD, by which I mean small and light enough to take on holiday.

sort of back on-topic... how are things going to work out for lenses on true consumer HD kit that's going to be taken on holiday. We have enough problems with DV camcorders that have cheap CCDs that are far too small with tiny pixels, and tiny lenses on the front of these isn't making things better. I can't imagine that consumer HD is going to be anything more than a big number on the spec sheet in much the same way as the pixel count has become the be all and end all of low-end digital stills cameras.

as for the HD100 being DV out only, i'm not really that bothered. At first it was a bit of a shock, but when you think about it, it makes sense. Why bother paying the import duty on an already expensive camcorder when most people won't use the DV-in feature anyway...? This really is prosumer with a big PRO and the target user probably isn't going to want to wear the heads out by using the camcorder in an edit suite.

It's also worth considering how the footage is going to be used - there's no way any serious distribution is going to take place on HDV, firstly because that would require either careful planning or everyone who accepts tapes to have 2 decks for HDV1 and HDV2. Secondly because there's no need for it - the infrastructure is (to a certain extent) already in place for HDCAM and DVCProHD. Certainly no broadcaster is going to accept an HDV Master.

As i see it, at this level HDV is an aquisition format. Footage will be edited and then mastered to another HD format, either tape-based or in the near future on HD-DVD/BluRay. Even more likely for the time being is that footage will be down-converted to SD, or maybe even shot in SD in the first place.

The long and short of it is that i don't see the lack of video input as too much of a problem. What would be a problem is if JVC really are considering shipping the HD100 with an SD lens, but i can't see them being quite that a) devious or b) stupid!

mark.

[infocus]

... how are things going to work out for lenses on true consumer HD kit that's going to be taken on holiday. ......I can't imagine that consumer HD is going to be anything more than a big number on the spec sheet in much the same way as the pixel count has become the be all and end all of low-end digital stills cameras.

Well...yeah, but no, but, yeah, but no but....... I stand to be corrected on this one, but it's not difficult to make a reasonably sharp lens quite cheaply. It's not difficult to make a fast lens, and it's not difficult to make a long zoom, and it's not difficult to make a lightweight lens. What IS expensive (and difficult) is to do all of it at the same time! Which is why true pro lenses, especially come HD, cost an arm and a leg. They DO need to have long zoom ranges, AND be wide at the wide end, AND be fast and not ramp, AND be very high quality - all at the same time. Low-end digital stills are a good analogy - they are capable of excellent results in good light, but don't begin to match the versatility of a good DSLR. You get what you pay for.

So hence I do think HD consumer cameras are viable, and do think there will be a big difference between such as them and current SD models. On the beach in good light with a limited zoom range, there's no reason why pretty good HD pictures shouldn't be got with a relatively small, cheap package. But they won't be as sharp as the latest HDCAM with HD lens, they will need far more light to work well, the lens coverage range won't be anything like that of the big camera etc etc. Sadly, I also think one of the reasons for their introduction will be the desire to put "HD" on the box for marketing reasons. Just as nowadays all DV cameras are far from equal, in spite of all recording the same signal to tape, so, I suspect, it will be with HD in the future.

I am thinking much more along the lines of a TRV900 size of camera than the tiniest palm cameras.

Regarding HDV back to tape, everybodys needs will be different. The use of Firestore may lessen the need for a tape deck to be used for capture, so lessen much of the need for a separate deck to lessen camera head wear. Yes, for cororate use etc in the future distribution will likely be Blu-Ray or whatever, but I think I'd still like the option of keeping a master of the edit on tape for the foreseeable future. And for that occasional use for many users, HDV-in is a must have. What does worry me slightly about JVC is their lack of up frontness about some matters, HDV-in being the latest, I wonder how many people may buy such a camera only to get a rude shock later?

[cstv]

indeed, John Kelly's (of JVC) words were "nobody's got a bad thing to say about it" and i'm begining to think that may be because JVC haven't given anyone the chance to find out about the bad bits yet... being stuck with progressive is one thing that they have mentioned a bit, but understandably their not shouting about it. lacking any inputs is as you say a bit of a shock, and while i don't think many people will be too bothered about it, it's always nice to know!

mark.

[Alan Roberts]

Gents, time for some explanations:

1: I was talking to a JVC rep yesterday at the BBD R&D Open Days. He assures me that the HD100 camera runs at 720p/50, but the recorder only records at 720p/25 because the required shipset for 50p isn't available yet. That changes my view of the camera part, it makes it a full-spec, proper camera, hobbled as a camcorder by the recording system. Full 720p/50 is avaliable from the camera for recording, but not via firewire yet because that uses the tape compressor chipset. So 720p/50 is available from it only as a video signal. All this must mean that there will be a MkII version of it, or a different model, that records 720p/50 properly when the chipsets are available.

I know that some of my stated views on this camera have offended JVC somewhat, I still hold those views, the camera's not suited for general use because it doesn't record 720p/50, yet. If Sarah wants a fight, I'll meet her for several rounds, with a referee (Ian?), in any pub :)

2: We need to nail this issue of the differences in resolution between i and p, 720 and 1080. As you might expect if you've read any of my interminable explanations, it isn't as simple as it seems, so I'm going to take up the suggestion of compiling a bit of the science and will make it sticky. It'll take me a few days to put it together, so bear with me for a while.

[infocus]

That nicely answers the question I posed in the first post in this thread -http://forums.dvdoctor.net/showthread.php?t=33628&page=1&pp=10 ! And hopefully puts to bed all the discussion about whether or not HDV1 is capable of supporting 50p - it obviously is, and the 25p only to tape is solely due to current hardware rather than a fundamental system limitation. Your use of "yet" regarding the 50p chipset is interesting, and begs several questions, like "when?" and "upgrade?" ;)

Alan - should your fight ever take place, you may at least like to make your opposition feel a little better by saying that at least they seem to be getting praise for the styling of the HD100 v the Z1 at this market point. I don't think there's been any fundamental disagreement on that in these forums so far..... anybody? Perhaps that's something that could be fed back to Sony as well.

And on the subject of manufacturers, could it also be fed back that consumers think it would be a jolly good idea if decks at least could playback HDV1 AND HDV2, even if they only recorded one or the other?

[Alan Roberts]

You can rest assured that at least JVC are reading this thread, and presumably other HD-related threads here. So you should assume that any suggestions you make here are getting to JVC, at least. I suspect that "other manufacturers" are also lurking :D

[cstv]

You can rest assured that at least JVC are reading this thread

so who wants to check the server's IP logs to find out who exactly has been lurking...? maybe it's a another 3:30am job for Mr C ;)

[David Jinks]

JVC kindly emailed me this week confirming the price of the optional Th13x3.5BRMU Fuginon 1/3" High Definition zoom lens.

Unfortunately, it looks likely to be tagged with a RRP of £5,860 excl. VAT
(double ouch !!)

I'm informed that its availablilty is likely to be from July as the camera itself.

An accurate 720/1080 breakdown as suggested by AR would be very welcome indeed. Keep up the good work !

Regards,

David Jinks.

[infocus]

Unfortunately, it looks likely to be tagged with a RRP of £5,860 excl. VAT
(double ouch !!)
When I first heard about it, I commented how desirable that lens seemed etc - now we know why! It really does make this camera a totally different kettle of fish now, no longer comparable price wise (with this lens) to such as a Z1. Any news as to the price of a package with this lens v the standard? Hence an idea of the cost of the standard lens by itself?

It does seem to indicate that the standard lens has a relatively low price comparatively, and that begs the question why - is it really a true HD lens, for example? Noting that the Z1 at w/a is 4.5mm (pretty average), the JVC w/a lens at 3.5mm was an immense step forward. If only the standard lens (5.5mm wide end) is realistically affordable for the intended market, that rather changes matters. (Might still be good for wildlife filming etc though!)

It would make me think that if I have to pay that much, to hell with it, how much extra is that 2/3" HD XDCAM....... ?

[David Jinks]

JVC have said that a body only option may be available at some point.
My local dealer is quoting the following pre-launch price :

JVC GYHD-100 PRO HD Camera
Fujinon T16x5.5 BRMU Zoom Lens
.44" Viewfinder
AA-P30 AC P/Adapter
Battery Charger
BN-V428
Plus:
JVC WVC-82SC Wide Angle Converter (list price £410 + VAT)
List price for all of the above is £4,200 + VAT

JVC have said the DV-in version (GYHD-101) of the standard package will be about £4,200+VAT

Regards,

David Jinks.

[cstv]

It would make me think that if I have to pay that much, to hell with it, how much extra is that 2/3" HD XDCAM....... ?

you'd still have to buy a nice lens for the XDCAM - the advantage of the HD100 is that the camcorder is cheap and will accept propper lenses. This actually makes perfect sense when you consider that a good HD lens bought in the next 6-12 months should still be usable in several years (hopefully!) but that camcorder will probably be superceded in a maybe a year. The only problem is the size of the lens mount.

The ability to use v-mount batteries is a good idea for the same reason.

mark.

[cstv]

JVC have said the DV-in version (GYHD-101) of the standard package will be about £4,200+VAT


Aha, so it's a nEUtered camcorder...? not seen one of those for a while. Did anything ever come of the letters that were sent to the widget makers asking them to stop in-enabling camcorders? If not then maybe we'll see a little box for the HD100...

[StevenBagley]

you'd still have to buy a nice lens for the XDCAM - the advantage of the HD100 is that the camcorder is cheap and will accept propper lenses. This actually makes perfect sense when you consider that a good HD lens bought in the next 6-12 months should still be usable in several years (hopefully!) but that camcorder will probably be superceded in a maybe a year. The only problem is the size of the lens mount.

But that's a huge problem -- the lens mount on the JVC is designed for (I think) 1/3" lenses while every other camera and HD lens uses a 2/3" B4 lens mount. Even with some form of stepping ring, the lens will behave very differently on a 1/3" camera compared to a 2/3" model (I suspect having the same effect as a 2x telephoto converter on it)

Which gives two problems -- any lens you own now won't work as expected on the JVC so people who have bought HD lenses for DV cameras such as the DSR570/DV700 won't be able to capitalize on their investment. Any lens bought for the JVC will be useless when the user upgrades to a 2/3" camera.

Which is why going straight for a 2/3" HD XDCam with a proper HD lens starts to look a more exciting prospect in the long term.

Steven

[Alan Roberts]

Exactly my thoughts. It's another reason why the HDV range still looks, to me, like a consumer range rather than a professional/broadcast range. If that offends anyone, I'm sorry, but it's an observation and not a criticism.

[infocus]

It looked at first as if the HD100 was going to be comparable in price to such as a Z1, and with the prospect of a 13x3.5mm lens that was a mouthwatering prospect. Now the details coming out that if with that lens it will be SUBSTANTIALLY more than the Z1, it becomes less attractive. We're now presumably looking at £8-9,000, which puts it in a different league - too expensive to be considered "prosumer", but with 1/3" chips and limited connectability still nowhere near the pro league. And yes, 1/3" lenses will be no use for any future upgrade to 2/3", and presumably will have less of a future resale market?

And with the standard lens 16x5.5, I'd argue that 5.5mm (11mm in 2/3equiv terms) is generally too tight for the wide end of the zoom in a camera for this market. The Z1 at 4.5mm has an edge on it. I don't think the wide angle adaptor is the answer either.

If HDV in is going to put £400 on the price, this could do wonders for deck sales, especially for such as colleges with more than one camera......

[Chrome]

Chaps,

I just thought I would make you aware... I got this a few days ago so they might have all gone. What IS interesting is they seem to have upgraded the viewfinder to a slightly larger one! :) I would have thought one that size might be a bit unweildy?

====
For the FIRST FIVE CUSTOMERS to order the camera on the back of this offer, SYMBIOSIS will supply the following:

To supply:

JVC GYHD-100 PRO HD Camera
Fujinon T16 X 5.5 BRMU Zoom Lens
44" Viewfinder
AA-P30 AC P/Adapter
Battery Charger
BN-V428

Plus: JVC WVC-82SC Wide Angle Converter (list price £410 + VAT)
List price for all of the above is £4,200 + VAT
However, our offer price for the above is just £3,395 + VAT + shipping (A saving of nearly 20%)

====

[Alan Roberts]

Getting a v/f that big's one thing, having to pay a 6-man crew to shift it about's quite another :)

[Chrome]

I'm wondering if the earlier postings fears were unfounded.
My thoughts are if they're offering it at £3.4k now then that will end up being roughly about what the street price will settle down around in a few months.

That large viewfinder is still putting me off though :)

[infocus]

I'm wondering if the earlier postings fears were unfounded.
My thoughts are if they're offering it at £3.4k now ..........
Those prices relate to the package with standard lens, whereas the recent posts were more thinking about the camera with the wide zoom. (A far more attractive proposition.) Earlier David Jinks posted that the price of that (the wide lens) would be £5,860+VAT, and I took that price to refer to the lens by itself - not a camera/lens package. That would infer a package price of £8-9,000, which starts to put it well beyond the prosumer price range. By the same token, even though presumably still well cheaper than the awaited HD XDCAM, it is nowhere near the standard of a true pro camera, so the question remains whether it will fall between stools or fill a gap neglected until now?

If JVC manage to bring in new chips, and get a 720p/50 version out, it could be Panasonic who feel the heat, since it then becomes more comparable to the HVX200 with a couple of P2 cards. From paper specs the HD100 with a Firestore and wide lens would then seem a more generally useful proposition than the HVX200.

There's always something new round the corner, but in HD at the moment there are huge gaps. Most notably between the Z1 and HDCAM. It's when product in the range in between starts to appear that HD will really become feasible for average broadcasters for mainstream production.

[Alan Roberts]

Well said. I think we're all using the same hymn sheet now. HDV is a consumer range that's gently extending towards, but not into, the prosumer range. There are plenty of slots for new kit to fall into, no manufacturer has yet fully cornered any part of this market.

[infocus]

HDV is a consumer range that's gently extending towards, but not into, the prosumer range.
I think there's a general problem with definitions, though I haven't got any good answers as to what they should be..... ;) If "prosumer" was previously defined by the PD170, the XL2 and their predecessors etc, then if we forget about the PD1, I'd say that HDV firmly started with the FX1/Z1 as a "prosumer" product, and is now moving gently upwards with the HD100 and gently downwards with such as the HC1. High Definition in general is, I suspect, waiting for two things, a true consumer camera, and a true professional camera at the bottom of the professional range - to be to HDCAM what such as a DSR570 is to DigiBeta.

I agree we are all singing off the same hymn sheet, it's the terminology that is serving to confuse rather than explain. Evaluation was easier when cameras and recorders were separate entities, the two parts could be evaluated independently.

[cstv]

i supose it depends on what you mean by "professional" really. Here's what wikipedia says:

A professional works to receive payment for an activity (as a profession), which usually requires expertise and carries with it socially significant mores and folkways. That is to say, behaving professionally would indicate that the person's actions remain in accordance with specific rules, written or unwritten, pertaining to behavior, dress, speech, etc. By extension, the adjective professional can indicate that someone has great expertise or skill in a craft or activity.

But a professional wedding videographer has different technical needs to a professional wildlife videographer who has different needs to a ENG camera operator who has different needs to a tv drama production team. All of them are professionals and all of them have very different kit and very different budgets.

I've always assumed Alan's definition of professional to be similar to "broadcastable" but that again differs depending on who's doing the broadcasting. BBC might be considered to hold very high standards, but that all changes when you start talking about channels like Discovery HD Theatre. The problem with broadcastable is that it only refers to the recording quality of the capture electronics and the recording medium and doesn't really take into account the creative and technical controls that a camara needs in order for people like Alan to work their magic and enable operators to achieve the derisred results.

I don't think we're ever going to reach an all-encompassing definition of professional camcorder equipment so the only way to decide if kit is good enough is to see if the industry is happy to use it. That does mean, however, that we'll continue to sit here and talk ourselves around in circles for the next 6 months or so... :D

mark.

[infocus]

Well, I'll certainly agree with the last sentence......

The term "broadcast" has lost most of the relevance it once had, and in this context I'd argue is now redundant. For reality work etc, broadcasters now sometimes use consumer grade equipment, and on the other side of the coin high end corporate work (non-broadcast) is often done with top end gear. In the past the main difference between "broadcast" and "non-broadcast" would be in picture quality, whereas now it may be argued that the differences are more usability, connectivity, flexibility etc than sheer technical quality on a bog standard scene in good light.

So where does that leave us? The terms "amateur" and "professional" have more relevance in that the former does something for the love of it whilst the latter does it for financial gain, but then as Mark says above there are many different shades of "professionals" who all have different needs of their equipment.

In some ways categorisation is a nearly impossible task, but at another level it is necessary in some way, to try and ensure like gets compared with like. Hence the term prosumer - equipment used professionally, but styled in a consumer fashion, and generally smaller, cheaper and lighter than what is normally referred to as "professional". This is what's so interesting about the HD100. Whereas most prosumer cameras are basically consumer cameras built to slightly higher standard, and maybe given a couple of "professional" features like XLR inputs, the HD100 seems to have come the other way. It seems to have true professional roots and styling, with less used features thrown off to get the price down. Whilst it may be let down technically somewhat by such as the 25/50p coding issue etc, it should be commended as a step in the right direction. I hope the likes of Sony are looking at it very closely.

Maybe in the future we will be talking more about equipment styled like professional gear, but used by consumers - instead of prosumer, what about "confessional" equipment, anyone? :)

[Alan Roberts]

My definition comes from the manufacturers; Sony and Panasonic have Professional/Broadcast and Consumer operations, sun separately. So PD170 is Consumer, but the 570 is Pro/Broadcast. Panasonic goes roughly the same. If there's one thing to separate the camps, I'd put it at interchangeable, standard, lenses.

[cstv]

So PD170 is Consumer

erm... are you sure about that...? vx2000 is consumer but i thought PD170 was pro? in the same way as the FX1 and Z1 respectively...

anywho a good point all the same and complicated even further when the different parts of the company don't talk to each other! That said, i've recently had more problems caused by an occasion when sony consumer and pro decided to work together... only now neither of them want to claim responsibility for the product! anywho... slightly off-topic rant over now.

mark.

[Alan Roberts]

Going back to what I said about where I get the definitions from, PD170 comes from the consumer division of Sony, 570 comes from the pro/broadcast division. The definitions aren't mine, but the manufacturer's. Similarly, the FX1 and Z1 both come from a consumer division factory. QED.

But I like the idea of "confessional" level kit :)

[infocus]

But I like the idea of "confessional" level kit :)
Glad that didn't fall on stony ground. ;)

But which do you like - the name, or the concept of "equipment styled like professional gear, but used by consumers "? (Definition copyrighted.)

[StevenBagley]

Glad that didn't fall on stony ground. ;)

But which do you like - the name, or the concept of "equipment styled like professional gear, but used by consumers "? (Definition copyrighted.)

Oh,

I thought it'd be equipment where the manufacturers told you what the problems were up front :P

Steven

[greg30]

can anyone tell me what the problem is with the hd 100 not having input? what would you use it for. I'm probably being dumb. also, anyone know if the lense issue has been resolved i.e. is it an sd lense?

thanks greg30

[Alan Roberts]

The problem with the HD100 not having input is that you can't record back to it from NLE. I've said this before: given the market that JVC are aiming at, record input isn't needed because professional users will not be using the camera during editing for tape access, it's only at consumer level that this happens. So they've added inoput in the 101, for extra money. Sounds ok to me.

As far as I'm aware, the lens is rated for HDTV, not SDTV.

[infocus]

MAY not be a problem, depends on your circumstance. Normal workflow would be to digitise tape to NLE (or use Firestore), edit, and ... now what do we do? In SD land the options are to lay back onto DV tape or make into a DVD. (Ideally both.) As yet making High Def discs isn't really yet an option for consumers, so that leaves back on to tape. Colleges, broadcasters etc are likely to have decks to do that, one man operations aren't, hence the desirability of HDV-in.

(Edit) See Alan just beat me to it! Worth mentioning that AFAIK the cost of DV-in is a percentage of cost price, levied as a tax. Hence quite cheap on a cheap camera - but a lot on one costing £3-4,000. Hence a deck looks quite a cost effective option the more expensive the camera!

[Chrome]

Just an interesting aside on the 'Broadcast/Broadcastable' issue mentioned earlier in this thread, and what is acceptable or not.

Today was the first time I have seen broadcast the main video picture on the news coming from a mobile phone. There was video from someone who had a phone on the Kings Cross train (I think), a few minutes of extremely poor quality footage. So in certain circumstances even almost the poorest video camera possible is 'broadcastable'.

[infocus]

So in certain circumstances even almost the poorest video camera possible is 'broadcastable'.
Agreed, and that's only the latest example as technology has changed. In the past 8mm film and later amateur video would be shown if the content warranted it, even against a background of strict union agreements. But I can't see all future drama moving over to camera phones somehow....... ;)

More seriously, I think research has shown that quality isn't worried about by audiences for short clips, but can be perceived badly if overused.

[Alan Roberts]

Interesting point about "Broadcast quality" versus "Broadcastable".

When I was working for Auntie Beeb, I had a lot of input into deciding what was broadcastable or not, image quality assessment was part of my job. The issue was never a straight judgement on the pictures, it always was a balancing act. You had to assess the quality in the light of the conditions; so a really crummy video-phone picture is most definitely broadcastable if there's no alternative. And that's the crunch, yesterday there were lots of people with video-phones on the scene, but transport for crews (and the availability of lots of crews) was the problem. As soon as crews got out and about, the pictures changed; that's the obvious and right way to deal with it.

Broadcast quality always means the best you can do in the circumstances, there is never a definitive statement of what it means because it changes all the time. If you're out to shoot a period drama, stately homes and big frocks, you'll want to do it on 35mm film or HD, the alternative of doing it on a single-chip DV camera is just silly. If you're out and about and something unique happens, and you're the only crew around and you've got a video-phone, you get the pictures because it would be silly not to (i.e. you'd miss the event if you waited for a full crew with broadcast kit).

This is always common sense. There are no formal rules, although I was on a project to formulate a way of assessing exactly where in the quality chain any single process of chain nof processes might be. So we can categorise capture and contribution, or more accurate we can peg them on a quality scale, but nobody's ever going to reject pictures of something important if they're the only ones available. Even when better pictures are available the crummy ones will be used if they fill an angle that the rest don't.

This has never been a problem in News, their jobs are to get stories told.

[David Jinks]

In response to Alan's comments about DV-in cameras.

The reasons I mentioned it in the first place were :

a) This fact was been overlooked by most who I had seen at shows and were interested in the product.
b) JVC weren't exactly publicising the fact (small print only)
c) Not everyone has access to a recording deck all of the time. If working remotely, but with two cameras, security copies can be made if at least one of the cameras is DV-in recordable. You need to "think outside of the box" on this one. DV-in is useful to have. (For instance, take a look at my website to understand the work, the places, it's limitations and potential hazards I can encounter)
d) HDV (to tape) is a tranistory medium. Unless HDV is being used extensively for commercial purposes I really don't think the deck would pay for itself in some cases. It may be preferrable to purchase the WA lens option instead (£5800++), or perhaps Firestore drives.

In these days of technological growth, camera bodies at this level are out-moded within 4-5 years. I'd prefer to get the most out of the device as possible.

This is one reason why I'm concerned about the mounting size of these lenses. Will they be of use to future cameras down the line ? Will cameras reduce in size so that this lens type will become the norm ?

Both lenses are HD rated, the comment from JVC was that the WA lens option is "more HD" than the standard. ie. I suppose better quality. A fact denoted by the model ID given by Fujinon.

David.

[Alan Roberts]

I'll not argue with any of that; DV-IN is always useful, but the pro/broadcast market JVC are aiming at will be much more likely to have pro kit around, so DV-IN is much less relevant to them.

HDV drops into a gap between SD and HD, the signals fit on an HDTV raster but are less "good" than "true HD" signals that costs lots more to acquire. Broadcasters using HDV for acquisition are going to dub to HDCAM pretty soon in the post operations, so being able to record back to the deck is pretty irrelevant to them. It's only in the consumer and low-end pro market that DV-In becomes relevant. Remember that HDV compression is pretty heavy, it's not something you want to do more times than really needed on a signal.

[infocus]

This is one reason why I'm concerned about the mounting size of these lenses. Will they be of use to future cameras down the line ? Will cameras reduce in size so that this lens type will become the norm ?

Who knows!? That said, my best guess is that 1/3" "cheap end pro" cameras will become more common, whilst 2/3" will still dominate for well into the future the higher up the market you go - they will always be more sensitive than a 1/3" camera, and always give more DOF control.

To David - absolutely right on the points raised above. My only comment would be that because DVin is "bought" in tax terms as a percentage of the camera cost, it may be more sensible to go down a route of buying a non DVin first camera, and a really cheap and cheerful (and yet to hit the shelves) HDV camera, just to use as an HDV in deck.

As for "b) JVC weren't exactly publicising the fact (small print only)", then if anyone from JVC is reading this thread I can only say they could do themselves a huge favour by being more upfront about their products, warts and all. In the case of the HD100 the other big wart being that it is 25p, not 50p to tape, and 50p is only available as analogue. Again, a fact very far from publicised. A marketing policy of "accentuate the positive" is one thing, but I know of at least one colleague who bought a PD1 and now feels grossly misled over the way it was advertised and presented, to the extent he is unlikely to touch anything from JVC ever again.

Quite a shame as JVC really do seem to have got their act together with the HD100. It has a few issues, but does promise much for the future, and hopefully may shake up such as Sony consumer to get their ergonomic act together.

[Relievo]

:confused: I feel queezy....

So are we saying the JVC HD100/101 is rubbish?
----------------------------------------------------

I haven't got a camera, and the last camera I used was an XL1s (I hated that one).

I just wanna buy a camera High Quality, that I could use to make promo stuff to make a living, but have the option to squeeze out a low budget feature film once in a while. -Films are what I want to get into.

HD100/101 is very £££, some people say its great, others are saying it's a thieving waste of cash?

The Z1 is more affordable, but whats the 'Progessive look' option like?

The more I read, the less I know! :o

[Relievo]

http://forums.dvdoctor.net/images/smilies/confused.gif I feel queezy....

So are we saying the JVC HD100/101 is rubbish?
----------------------------------------------------

I haven't got a camera, and the last camera I used was an XL1s (I hated that one).

I just wanna buy a camera High Quality, that I could use to make promo stuff to make a living, but have the option to squeeze out a low budget feature film once in a while. -Films are what I want to get into.

HD100/101 is very £££, some people say its great, others are saying it's a thieving waste of cash?

The Z1 is more affordable, but whats the 'Progessive look' option like?

The more I read, the less I know! http://forums.dvdoctor.net/images/smilies/redface.gif

[DVdoctor]

The lack of HDV in of course goes back to the silly outdated EU protection import duty that was designed to protect EU based VCR manufacturers??? anyone know of any EU based VCR manufacturers? with HD?? of course not, so that whole tariff is completely outmoded. One of these days someone will wake up and decide to repeal this tariff. I would think that one option for storage and interchange might be the WMP 9 hd format.

John

[DVdoctor]

I asked some friends at MS to give me some suggetions on using WM9 for HD and they sent me this link Unofficially (especially since it offers links to non MS products. BUT it makes for an interesting starting point. Some of the comments on how to get the performance to work better on endoding are pretty usefull

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=227837

John

[Alan Roberts]

I, for one, am definitely NOT saying that the HD100 is rubbish. From the spec., it looks very nice if what you want is a camera that shoots 720p/50. BUT, if you want to record it, the recorder won't do it justice because of data-rate rectrictions. The fact of having a removable lens sets it apart from all other HDV offerings.

In my book, there are two factors that differentiate professional from consumer camcorders:

1: removable lens
2: viewfinders that don't overscan

The HD100 scores on #1, and I'm not sure about #2 until someone tells me what the v/f does. If it overscans, then the camera lives firmly in the high end of cosumer products. If it doesn't, it lives in the low end of professional.

[Relievo]

[QUOTE=Alan Roberts]I, for one, am definitely NOT saying that the HD100 is rubbish.[QUOTE]

Good enough for me!

[infocus]

In my book, there are two factors that differentiate professional from consumer camcorders:

1: removable lens
2: viewfinders that don't overscan
I've heard worse definitions, but I think they are pointers rather than defining factors. Imagine for instance a "Matteo modded" FX1, done to enable it's use with a wide zoom lens (like the 11x3.5 promised for the HD100). Optically and technically it may work fine, but in real usage, at least hand held, I don't think it would be a starter in ergonomic terms.

The real advantages of interchangeable lens cameras are not so much that one can, errrr, interchange lenses, but that they tend to have responsive focus and iris adjustability, and the most appropiate lens can be purchased initially. That leaves the XL range as a bit of an oddity, interchangeable lenses, but appallingly "steppy" control of iris.

The HD100 has a few marks against it, but it is far, far from *rubbish*, and is arguably the most professional of the cameras in this price range by quite a long way. At least until the next milestone comes along. :)

[Alan Roberts]

Agreed; I wasn't suggesting that those were the only differences, just that they're highly significant. Interchangability of lenses lets you use proper separate lens controls, and a non-overscanning v/f lets you see what you're shooting, two absolute requirements for grown up cameras.

[Mad_mardy]

in one post what are the few things against the hd100/101?

[StevenBagley]

in one post what are the few things against the hd100/101?

The major one is that you are limited to high def spatial resolution and jerky motion or smooth motion and standard def images when recording to tape.

Steven

[infocus]

in one post what are the few things against the hd100/101?
As Stephen says, or to put it another way, it will only record an HD signal at 720p/25, rather than the preferred 720p/50 (or 1080i/25). Used SD and 576i/25 it obviously has no disadvantage compared to the opposition.

There is also the matter of lens coverage. With standard lens and no convertor, w/a is a fairly tight 5.5mm, compared to 4.5mm of the Z1. Using the optional wide lens on the HD100 brings this to an extremely desirable 3.5mm - but virtually trebles the cost, oh well!

[Mad_mardy]

I was thinking of getting it for mainly SD work at the moment
how do you think it would compare with the sd camera's around at the moment OR recording HD and then doing SD dubs for editing as it seems to output sd from recorded HD (composite out i think)

[Alan Roberts]

My biggest gripe about it is the 1"/3 sensor size. It means that other standard tv lenses are of little use on it (they're mostly 2"/3 or 1"/2 format) unless you're happy to use an adaptor (and that can give misleading lens angles). Also, since you're using only the centre of such lenses, the resolution's lowered significantly. Add to that, the depth of field is huge since the sensors are small, so you need the lens wide open to get any DoF differentiation in shot. Plus, the diffraction limitation means that pictures get softer as the lens stops down beyond about F/5.6, not sharper.

This camera comes at a time when the cinema industry is busily developing large-format cameras (35mm film frame or bigger). That doesn't make it a rubbish camera, it makes it a camera with huge DoF, and that means it won't get a lot of use in serious drama or film unless budgets are firmly screwed to the floor.

All that said, I like the package, it's easily the best of the HDV offerings so frar.

[Mad_mardy]

now i know it shoots at 720p25
but according to the brochure it seems to be able to output via component
at 1080i50 any thoughts.
i could be wrong i may have mis read the brochure and it does say component out on the specs but i can't see component out on the pics i have seen

[Alan Roberts]

No, it shoots at 720p/50. The camera, that is. The recorder throws away alternate frames and records at 720p/25. That's what we've been going on about for so long; it's in the spec., not in big print, but it's there and has been confirmed by me in conversation with reps from JVCPro.

The camera can upconvert it's content and output it as 1080i/25 (meaning 25 frames per second, interlaced, what used to be known as 50Hz interlaced), and if that upconversion is directly from the camera, it should have 50Hz motion, but if from tape it'll be jerky like film because alternate frames have already been thrown away.

I can see that I'm going to have to get on with that big posting of resolution and rates that I promised to do a while ago.

[infocus]

My biggest gripe about it is the 1"/3 sensor size. It means that other standard tv lenses are of little use on it (they're mostly 2"/3 or 1"/2 format)..........
All true, but now we're starting to compare it with true pro cameras, which is interesting in itself. In no respect does it challenge the likes of an HDCAM - but then it is far, far cheaper, and for some work the small size/weight (enabled by 1/3" chips) may be an advantage in itself. Pricewise, the comparison should really be with the likes of the Z1, and from the brief hands on and paper specs I've experienced so far, in usability terms it seems to beat the Z1 hands down. Used for SD the thing we've been banging on about (720p/25) becomes irrelevant, so for SD widescreen work I'd definately consider it far superior to such as a Z1 for a similar price.

For SD the only downer remains lens angle with the standard lens at it's widest setting (5.5mm). For some types of work the 4.5mm of the Sony Z1 could be more suitable. It remains to be seen what the sensitivity is like.

[Alan Roberts]

Aw, c'mon, you got to let me fit it into the total scale of things. Sensitivity should be better than FX1/Z1 because the pixels are bigger, but they could have traded off some or all of that in exchange for latitude (and that would be a big plus in my book).

[cstv]

IIRC they guys at JVC did mention something briefly about the overscan on the viewfinder beign one of the things that the engineers were still working on... wouldn't it be useful if i could remember what it was they said?!?!

Used for SD the thing we've been banging on about (720p/25) becomes irrelevant
in fact the HD100 will record 576p/50 as an mpeg TS - that's got to be quite usefull in itself...

[infocus]

Aw, c'mon, you got to let me fit it into the total scale of things. Oh yes indeed, no complaints! I just think it says a lot that the HD100 is being automatically and subconsciously compared to "true pro" cameras costing many times more, whilst all the FX1/Z1 comparisons I've seen compare them to such as the PD170 etc.
Sensitivity should be better than FX1/Z1 because the pixels are bigger, ........
This is now harking back to things said earlier about maybe 720 is a better option for this type of camera (1/3" chips). Maybe a better compromise between resolution/other performance aspects than HDV2 and 1080i? And leaving true 1080 to cameras with bigger chips? Especially if JVC get to record the full 50p to tape.

[cstv]

Especially if JVC get to record the full 50p to tape.

give 'em time... they'll get there...

if they threw the tape away i suspect they'd do it tomorrow. the problem is that they couldn't squeeze so much data into the part of the track that they use for the TS reliably. Take the tape away and you say goodbye to the 19.7Mbps limit. Then they'll replace the encoder chipset with one that will encode the 720p/50 to MPEG TS and you can do what you like with it - hard drive, solid state, firewire, whatever!

in fairness, analogue component 720p/50 really ain't that bad for the money we're talking about here.

[infocus]

if they threw the tape away i suspect they'd do it tomorrow. the problem is that they couldn't squeeze so much data into the part of the track that they use for the TS reliably.
Don't think that's true, I'm pretty sure I was told it's due to the coding chips in the camera. I'm also pretty sure I saw a PLAYBACK demo of 720p/50 HDV1 - obviously not recorded on an HD100. There should be NO theoretical problem with 720p/50 MPEG 2 at about 19Mb - that is, after all, roughly what all the US HD 720 broadcasts are.

[Alan Roberts]

Take the tape away and it isn't HDV. HDV's a tape format agreement.

When you start talking of the recorded bit rate, you need to do some sums, here's a quick run down of the basics (totally ignoring sound and metadata):

1080i/25: image size is 1440x1080 so total pixels/frame is 1.555,2M. With 4:2:0 subsampling for colour, the colour resolution is 720x540=388,8k for each of U and V, giving a grand total of 2.332,8M. 25 frames/second gives a vision data rate of 58.32Mbytes/sec, uncompressed.

720p/50: image size is 1280x720, 921.6k. With 4:2:0 again, colour is 640x360=230.4k for each of U and V, grand total of 1.382,4M. 50 frames/second gives a vision rate of 69.12Mbytes/sec.

So, you can easily see that 720p/50 needs to be compressed harder than 1080i/25 to get it into the same tape bit-rate. Conversely, it's a darn sight easier to get 720p/25 to tape simply because it needs only 34.56Mbytes/sec. In round figures, if 1080i/25 fills 25Mbits/sec, then 720p/25 fills 25*34.56/58.32=14.81481Mbits/sec if it has the same compression ratio. And that's why the JVC can get away with using only 19Mb/s. They're going to have a big problem getting 720p/50 onto tape at sensible quality unless they can come up with a better compression algorithm than the one they're using now.

And that's why this is such an interesting problem, there's no simple solution to it yet.

[infocus]

Is not that explanation missing the progressive/interlace argument? Hence, although the 720p/50 signal may start off with a lot of bits, it's inherently easier to compress than 1080i/25, being progressive? By similar argument I would not expect a 50p signal to need twice as many bits for comparable quality encoding as 25p - in simple terms the differences between frames every 1/50 sec will be less than every 1/25 sec, and presumably longer GOPs could be used, with more frames to the second.

[cstv]

bear in mind that the data recorded to tape and the data broadcast for HDTV will be slightly different. I'd hope for increased reliability in an aquisition format which generally means increased redundancy. Maybe since it's a consumer format that's not the case. The guys at JVC also said something about the data that's used to make up an image when you're scanning through the tape at higher speed, which again reduces the number of bits available for the TS.

I totally agree about the interlace / progressive encoding though. complete frames should be easier to compress to the same perceived quality.

i wonder what happens if you take 720p/50 from elsewhere, wrap it up in an HDV-compatible MPEG TS and pump it out to an HD101 over IEEE1394... do we think the electronics in the HD101 would realise it couldn't decode it and stop recording, or would it allow the dump to tape anyway? might be an interesting experiment... i suspect it won't work though. maybe someone could try something similar with a Z1?

mark.

[infocus]

I totally agree about the interlace / progressive encoding though. complete frames should be easier to compress to the same perceived quality.

i wonder what happens if you take 720p/50 from elsewhere, wrap it up in an HDV-compatible MPEG TS and pump it out to an HD101 over IEEE1394... do we think the electronics in the HD101 would realise it couldn't decode it and stop recording, or would it allow the dump to tape anyway?
I think it would work. My understanding was that the HDV1 spec *is* 720p/50 and this is always recorded to tape, hence a Firewire input on the HD101 or whatever should be expecting this. I thought the HD100/101 could only encode 25p, but then duplicated every frame to record the standard 720p/50 HDV1 signal to tape. In other words, the problem lies within the chips of the camera, and nothing to do with the basic HDV1 spec.

My memories of the JVC demo I saw were of two HD monitors, one displaying an HD100 "live" (via component, so hence 720p/50), the other showing an HDV recording. The information wasn't volunteered, ( ;) ) but I'm pretty sure I was told this latter was 720p/50, BUT had been shot on a different camera and converted to HDV - it was standard HD stock footage. Later some genuine HD100 material was played, and then the "film jerkiness" could be seen on movement. It wasn't unduly unpleasant, and for lovers of "the film look" would be seventh heaven, but nice to have the option of true 50p.

[Alan Roberts]

The interlace/progressive argument is the one excercising broadcasters all over Europe at present. If all other things are equal, then the difference between prgressive and interlace is about 30% in perceived resolution, i.e. 1080i/25 has about 70% of the vertical resolution of 1080p/25. So you could add about 30% to the bit budget for compression. On the other hand, 1080i images have vertical filters to prevent excessive interlace twitter, and that's controllable in the camera (the dreaded detail enhancement) so we can't be didactic about it. And it means that the bit budget difference is less than the 30% you'd expect, more like 20%, and that puts 720p/50 fairly close to 1080i/25 overall. Which is why it works.

There's a lot of work been done on compression for tape, and the rules aren't obvious. Mark's right about "pictures in shuttle". You can get much better compression algorithms if you don't need pictures in shuttle, DV's compromised by that, so HDV must be as well. And this means that the DV or HDV footage is an inefficient way of keeping it on disk, you can get a significantly better usage of storage if pictrures-in-shuttle isn't needed. This is one of the reasons why DVProHD has more artefacts than HDCAM, it's 6.7:1 rather than HDCAM's 4.3:1; the artefacts are rather more visible than that comparison would lead you to expect, DVCProHD survives because the compression blocks are smaller so the artefacts exist in smaller clumps.

[StevenBagley]

Is not that explanation missing the progressive/interlace argument? Hence, although the 720p/50 signal may start off with a lot of bits, it's inherently easier to compress than 1080i/25, being progressive?

This must be some new meaning of the word 'easier' that I was not previously aware of. :)

While, mathematically, it is much easier to compress progressive over interlaced material or to put it more precisely there is more redundant information in a progressive system. This doesn't mean it is 'easier' to actually compress it in real-life.

Since 720p50 has such a higher datarate (in the region of 11MB/s (that's about 3 streams of DV!) than 1080i25, it means that my encoder is going to need more memory to store the data and be faster to process it all in the same timeframe. Now memory is cheap, but speed isn't. So the chip either becomes more expensive because it's faster (and so requires more power, generates more heat etc etc etc) or you simplify your compression algorithm at which point it is no longer as efficient and your output gets bigger for the same quality.

Actually, there is a very simple way for JVC to record 720 @50Hz to tape now using currently available tech. Either record it as 720i50 (and deinterlace it back to 720p on playback) or upconvert it in camera to 1080i25 and downconvert to 720p50 on playback :)

Steven

[infocus]

This must be some new meaning of the word 'easier' that I was not previously aware of. :)

All right, but I did say "easier" - NOT "easy"! ;) The point I'm trying to make is that uncompressed data rates are only part of the story, and progressive/interlace is another, so taking raw data rates in isolation doesn't give the full picture. Yes, the compression of the 720p/50 that the basic camera produces will take a lot of power - and THAT (I believe) is precisely why the HD100 doesn't do it, rather than there being any intrinsic technical limitation within the HDV1 spec. Come improved, more powerful, coding chips and I don't believe there is any fundamental reason why we won't see the 50p option.

[cstv]

Actually, there is a very simple way for JVC to record 720 @50Hz to tape now using currently available tech. Either record it as 720i50 (and deinterlace it back to 720p on playback) or upconvert it in camera to 1080i25 and downconvert to 720p50 on playback :)

erm... "720i50" in the new terminology or the old style? ie. did you mean 50 fields or 100 fields per second? and are we still working with a 720p/50 source here?

and all that conversion can't be good for the image quality.

[StevenBagley]

erm... "720i50" in the new terminology or the old style? ie. did you mean 50 fields or 100 fields per second? and are we still working with a 720p/50 source here?

and all that conversion can't be good for the image quality.

oops I of course meant 720i25

Although 100 fields a second would be nice :)

as for image quality -- how much it'd suffer would depend on how good your algorithms are :) but it could never be better than true 720p50.

Steven

[cstv]

100 fields per second would be nice... bit of a shame it would have the same data rate as 50 frames per second... :D

[Alan Roberts]

JVC's problem with 720p/50 is not tape capacity but coding hardware.