WB Question

[Goldorak]

This may be a naive question, but I'll ask anyway:

I understand that an 18% gray card should be used when photographing subjects under difficult indoor lighting, such as in bathroom.
Now, for the naive part: why not use this Custom WB setting for all types of shooting (i.e. ourtdoor, sunlight...) as it will produce almost no color cast?

What's the more efficient way to set then assign this custom WB on the Rebel XT? I mean, how do you accurately photograph a white/gray paper (should it occupy the entire viewfinder or the center only? Should the flash be used or ISO boosted up?)

As you can see, I'm quite a bit confused with WB...

Thanks.

[Chucko]

The Custom WB setting can be used any time the lighting conditions are constant. It's not much use when the lighting is constantly changing, for example on a partly cloudy day when the sun is intermittently blocked, or at sunrise or sunset.

I'm not familiar with the XT/350D. I believe the grey or white card has to surround the partial metering circle on the 10D and 20D. RTFM (Read The Fine Manual) to be sure. The manuals are downloadable from Canon's web site.

[Chucko]

And by the way, if you shoot raw, you can adjust white balance during post-processing in Digital Photo Professional, or Photoshop's Adobe Camera Raw plugin, or ...