5D MkII: Histogram Specifics

[thinkstopthink]

Hi,

Searched the site but didn't find the info I'm after. I think the Histogram section of the manual ought to explain what the controls do, instead of just sending you off to LL's page on reading a histogram. I know how to read one, I just would like the controls explained. Specifically the Clip Warning settings. This is what I'm assuming:

1% px shows a warning when 1% of the pixels are clipped. Etc., for 0.1% px, and so on.

With the camera set to 1/3 stop aperture increments, the difference between 0.1% px and 0.01% px is not noticeable, as the percentage increment is smaller than the aperture stop increments.

I guess I'm curious why someone might use 0.001% px over, say, 1% px. I would think a .5%/1%/2% spread might be more useful? Just curious, ya'know.

I also shot two frames with the same clip settings. But, I switched between Luma and RGB. In order to not clip the any of the RGB channels, I had to shoot at 1/2500. With Luma, the exposure was 1/1000, ceteris paribus. However, when I looked at both images' histograms in LightRoom, neither had clipped (as expected) but the RGB indicated image was, again as expected, exposed less. I guess I didn't expect that much difference.

I just trying to decide why one would choose YUV or RGB in particular.

What a wonderful feature! I am really enjoying digging around in the menus and finding such useful tools!

Jon