On Oct 30, 6:28 pm, Shawn Hirn <s...@[EMAIL PROTECTED]
> wrote:
> In article <1193733169.993827.142...@[EMAIL PROTECTED]
>,
> The Translucent Amoebae <transamoe...@[EMAIL PROTECTED]
> wrote:
>
>
>
> > i think about them this way...
> > Brightness seems to increase/decrease the whiteness of all pixels
> > uniformly
> > Contrast seems to make dark pixels darker, and light pixels lighter
> > Exposure is more complicated;
> > When you lighten a picture, the light pixels get lighter, but the dark
> > pixels remain pretty much the same darkness. This occurs along a
> > curve, so the dark pixels are effected, but not by as much.
> > likewise, when you darken a picture with Exposure, the dark pixels get
> > darker, and the light pixels remain pretty much the same.
>
> > i do use the Levels controls, and i've noticed that when the spikes
> > are clumped together in the middle, and i slide the dark or light
> > towards the mountains, it seems to bring out detail by enhancing
> > surface texture with local contrast...???
>
> > But i STILL don't SEE what the mountains are supposed to be
> > representing...
> > Obviously; it's a graph of somekind, and as such, the x & y axis must
> > represent SOMETHING...???
> > But i just don't see what...???
>
> I just googled for "digital photo histogram" and the first hit
washttp://www.photoxels.com/tutorial_histogram.htmlwhich
does a good job
> of explaining what the histogram means.
Thanx, i have never been able to figure out how to get search engines
to return anything useful either...!!!
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