White Balance Questions

I read with interest the previous 'white balance' question. This brought to mind my issues with white balance. I tried and tested, compared and contrasted etc all the different options Canon gives for w/b on the XL1 and could not find a satisfactory one - The 18% gray card that is suggested there sounds like a potential solution - two questions then: where can someone in the uk get hold of such a card, and, when white balancing, is it best to have the light source shining directly onto the card, or have it facing elsewhere?

Your knowledge would be greatly appreciated folks.

[Chris Hurd]

As to where to find an 18% grey bounce card -- any photography store that sells still photo cameras and assorted supplies will have one.

[Casey Visco]

when white balancing, you want to balance for the lighting that is falling on the key part of your scene. light the scene to taste, then place the card where the principal action in the scene will occur. if your lighting for an interview for example, have the interviewee hold the card right where his head is, and adjust your balance.

another note, i dont know if this was mentioned previously: if you want to preserve color effects from gels, light to taste, and remove the gels to white balance, then place them back on the lights and roll.

my 2cents
c

[Ron Pfister]

But what do you do when you have no control over the lighting, and you want to, say, give a scene under an overcast sky a warmer look?

I have experimented with negative compensation (i.e. if I want a more yellowish look, I white-balance with a blue filter in front of the lens). Any proven recipes here? What filters do you use for what effects, etc.?

Any hints would be highly appreciated!

Cheers,

Ron

[Casey Visco]

ron -
to be honest i usually handle these type of situations in post. call me a computer geek, but hey it's just what works for me ;)

but i'd be interested to hear what others have to say about the in-camera aspect of it, as im sure i'll run into that problem as well.

-c

[John Klein]

1st

On the xl1s, there are manually preset white balances, i.e. one for daylight and one for incandescent light. If you used the daylight one, and it was around sunset, my guess is that it should give you a reddish look because it's set for daylight, but the light itself is red. If it's overcast it would likely be more blue. Which is what you're trying to avoid, right? But if you like the morning or evening light, like most films are shot then, that's where I'd start.

2nd

Don't do that filter trick.... it's going to be overkill. Try taking a white sheet and put some (color) dots on it (maybe 1-3% of the paper)with a magic marker. Then manually do the white balance proceedure (and fill the frame with the sheet). This should change the balance some, but not too obvious a change.

Usually with Canon's, they are too warm to begin with. I'd try some red dots to fool the camera to go cooler. You want more warmth, try some cyan dots.

It might make sense to make a few of these cards up for the different corrections that are needed from time to time.

[John Klein]

3rd

Just use a white piece of paper to do the white balance.

No 18% gray card needed. 18% grey is half way between black and white. It might be okay to use because there is no "color" on it. I WOULD use it to white balance and then lock my exposure.

In theory, the cam's light meter is set to the same 18% gray. That way if the cam is set up properly and you lock the exposure (on the gray card), anything lighter than middle gray is lighter and anything darker is darker.

Trouble is, when shooting, you never get things that are perfectly in that middle zone. I'm sure you've shot someone against a white wall and the meter in the cam says...whoa...too bright and knocks the image back to middle, 18% gray. I just know through experience that if my subject is on a light colored wall, I need to bump it up a couple/few clicks. If I had a gray card, I could just lock the exposure and let the light fall where it will.

Last, don't forget that the lens' aperture changes at different focal lengths. So you've got to be cautious about when you lock that exposure. If you zoom to much (from where you did your metering/settings) you will lose some light.

[Casey Visco]

as far as the filter trick goes, i would imagine you could get away with using a 1/8ctb or 1/8cto or cts for subtle effect. 1/8 changes the color 300 degrees... anything higher than that would produce a very noticeable shift in the color of the scene.

my .02
c