Over exposure

[Nintembo]

Hi,

I was shooting with my FX1 down my local park last week, and I realised that my backdrops were subject to major over exposure. (My zebra gauge was having a field day)

Without the funds to block out the sun, I was wondering what you guys think the best methods of reducing this problem are?

Nin

[Unicorn]

Did you have the ND filters on?

[Nintembo]

At one point yes, it was flashing ND1 on the screen so I took this as a prompt and turned it on - it didn't seem to do much...

[MattDavis]

It's a darn shame the FX1 hasn't got Black Stretch - I shot an event this weekend (I'm passing time during the ingest) on a Z1 using Black Stretch which allowed me to expose for the highlights without the shadows disappearing down a deep dark well.

Certainly CineTone should help ramp off the highlights but you'll lose a bit of video 'zing'.

Some silly tricks:
- Polarising filter, grads, etc to darken sky (polariser will intensify colours)
- Wickes or B&Q polystyrene sheets (thick insulating stuff) to fill shadows on subject where sunlight is too strong (tempting you to shoot into sun, hence blowing out background)
- Big white brolly to partially shade subject when the sun's behind you (so they don't screw their eyes up)

NDs won't visibly do much, but they help when the camera runs out of iris to stop the lens. By the way, the Z1 manual says the lens loses quality at small iris settings (f11 onwards), so whack in the ND2 to get around f8 (sun behind you) to f5.6 (shoot into sun - and for gawds sake keep the lens clean to improve contrast :) )

[Alan Roberts]

F/11's a bit small, I'd not go beyond F/5.6 if you want to keep maximum sharpness. I wouldn't even use F/11 on a 1"/3 SD camera, let alone on an HD version.

[tom hardwick]

I'm with Alan here. Apart from the vignetting issue (and all cameras suffer this) the FX1 will give better and sharper pictures wide open at f1.6 than it will at f11. This surprises many folk who've come to DV from 35 mm film, say, where diffraction was hardly ever an issue.

tom.

[MattDavis]

I think we're all in agreement - I wasn't advocating small stops, merely pointing out that even with the ND2 engaged, my shoot in a sunny park this weekend had me using f5.6 to f8 at 50th (not wanting to use higher shutter speeds).

Just pointing out the sage advice in the Z1 Manual, and more importantly, feeding these limits into my little "list of Z1 Picture Profiles". :)

[tom hardwick]

As the PD170 / VX2100 is a good stop more sensitive than the FX1, the same sunny park conditions find me filming at a dangerously small f/9.5 to f/11 aperture. This with both the NDs engaged, and as I'm not one to faff about screwing ever more filters into position, I often have to resort to higher shutter speeds just to soak the light.

It means going to 1/215th sec to let me open to f/5.6, but I'd hesitate to select a faster speed, even if it's just wedding guests in my v'finder. If you're shooting action I'd not recommend this technique - go for an ND8 and keep the shutter speed at 1/50th.

We've rather strayed from Nintembo's original post, but hey - it's all good fun.

tom.

[Des]

What's wrong with shortening the shutter speed to keep the aperture open when ND2 is on?

[MattDavis]

What's wrong with shortening the shutter speed to keep the aperture open when ND2 is on?

PMJI - but using really fast shutter speeds make quick movement a bit... uhm,... "whammery". Great effect in its place, but it breaks up all the fluidity. For example, note the difference between straight Flash style animation and expensively motion-blurred graphics on an interlaced monitor. All that blurriness goes down the swannee past 100th sec.

It can feel like scrubbing your teeth with a wire brush and dettol. :D

[Des]

So if you don't have a pan or track on the shot and have slow movement within the frame it would be ok - especially landscapes when the light hits hardest?

[tom hardwick]

Yes it's ok to up the shutter speed because it means you have to open the aperture to compensate. But apart from the stacatto effect on zooms, pans and subject movement, upping the shutter speed makes a lot of camcorders very prone to CCD smear. The Canon MVX3i and Sony TRV950 are terrible in tis respect, and upping the shutter speed should be avoided.

Beware though, as some camcorders up the shutter speed without telling you, as part of their auto exposure programming.

tom.