We make a trial exposure
and review it.
On our digital camera
backs, we see flashing when highlights lose detail (are blown
out). That’s the first thing we check. We know that in the RAW
mode we can recover some highlight detail that appears blown
out, but there’s no reason in a white on white image to force
that issue. (Note: in some compositions we might choose to
design the image with some highlight detail blown out.)
The second thing we
check is whether there is adequate separation between the
various white components of the composition. While this can be
enhanced later in Photoshop, we may find that a new camera angle
will improve on the situation.
The third thing to check
in the review screen is the histogram. If your composition is
truly shades of white, the data recorded on your histogram
should show up in the right 1/2 to 1/4 of your graph. You don’t
want the histogram crashing into the right edge of the graph –
that would indicate blown out highlights as discussed above.
And, you don’t want too much data wandering down into the mid
tones (unless there truly are some mid tones in your