Renee choreographed a chorus line of high-kicking electrons to spell
out:

[snip]

After perusing the internet, it's my understanding now that you only
do a custom white balance adjustment indoors when you're shooting
without a flash. Maybe that's what you all meant, and I somehow missed
the point. Is this correct?

Custom WB has a lot of uses indoors, yes. "Only?" Not
necessarily, but indoor lighting can be very hard to pin down.

I've only played around with the presets
and haven't tried to do a custom white balance with my camera yet. I
wonder whether the custom adjustment will work, as someone mentioned,
on a white spot instead of using a white paper or gray card. A spot
would be much more convenient for casual shooting. Will it work if the
white spot doesn't completely fill the center of the frame?

"Spot" as in a highlight on a surface? A totally white highlight
is not a good idea since it might not have any underlying color info. It
also might not be totally white, if the surface underneath is colored.
You can get a Custom WB point from a not-totally-white frame, but filling
the frame is safer. A small gray card or a fresh white index card can do
the job if you're holding it close to the camera lens, just make sure
that it is not in your own shadow.


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