Filters on camera

[Johnc]

Hi.
I use a Canon Hi8 which has auto exposure which I can lock on to a scene (ie point and auto focus/expose then lock the exposure). The camera has manual focus also. I do not use editing software that has the facility to colour filter.
If I use, for example, a blue filter to make "moonlight" I assume I lock the exposure and then screw the filter on? If I put the filter on first before locking the exposure the camera would, presumably, automatically compensate exposure and white balance and prevent the effect?
Any advice/comments (apart from "get Premiere or MSP"!) will be much appreciated.

[Unicorn]

For 'moonlight' shots in the past I've just zoomed in on a streetlight and set the white balance on it; the camera compensates for the orange light by shifting the white balance to blue.

Otherwise you definitely need to lock the white balance before attaching the filter (or use one of the presets), as the auto white balance will remove most of the blue tint.

[gadget]

John,

I am not familiar with your camera, but the key thing you want to do is to stop the camera automatically white balancing with the filter in place. If you expose before fitting the filter, depending on the transmission of the filter, you will get an under-exposed image.

I don't think white balance is normally adjusted along with exposure (but I am not that familiar with consumer cameras, and could well be wrong in your case).

Perhaps you could switch white balance to manual (or 'daylight' preset), do a correct balance (without the filter), put the filter on and then do a correct exposure separately.

As Unicorn suggests, an alternative way of getting a 'blue' looking picture is to do a manual white balance whilst pointing at a slightly redish image. The camera will then 'incorrectly' compensate as if red was white, resulting in a slightly blue image.

Neither method is as good as using decent lighting (with some blue gel) to create a moonlight effect with a correctly balanced camera - if this is possible.

Hope this helps,

Gadget

[Tarun]

In the film world it was called 'Day for night'(English title for a Truffaut film 'la nuit americane' excuse my french i am from colonised india). Usually in film shoots with artificial light, the film used is Tungsten Balanced, meaning it sees white as white under Tungsten light. For doing Day for night you shot at dawn or dusk when street lamps are on, house light on and then with tungsten balanced film in your camera the the sky would register deep/ dark blue, the shadow areas would have blue moonlighty cast.
In video lingo- you still shoot at dawn or dusk, but shift the white balace of your camera to tungsten (or a flashing bulb sign).
Obviously you can use blue gel on lights etc... but imagine lighting up the whole street... if you have HMIs/5000w arcs go ahead and do it.
(And people here seem to be confusing between colour filters and aolour correction filters. For instance 80b or blue colour correction filter corrects for tungsten light when your white balance is set for daylight. But blue filter would colour the whole scene blue even if you white balance your camera.
You use colour correction filters/gels when in mixed light situation to make scene look realistic. For example you are indoor in day with artificial light and a big window, whatever lightsource you white balance for you would either get very blue window or very red l, solution- put 80a 0r 80b gel on the lamp and white balance for daylight or put a 82a(?)/amber gel on the window and white balance for tungsten. Get a book of still photography and swot on Colour temperatures)