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Category: New Questions

Photography Question 
Steven Chaitoff
BetterPhoto Member Since: 6/22/2004

Photoshop Levels

Ashamedly, as long as I've been using Photoshop, I've never really understood how Levels work, so I've managed to do all of my editing without using that tool. How exactly is Photoshop modifying the image when you drag any of the 3 input arrows or 2 output arrows? I can't seem to get a feel for it myself by playing around with the sliders and watching the histograms.

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6/3/2005 11:22:45 AM

Andrew Laverghetta
BetterPhoto Member Since: 9/13/2004
  When I mess with levels, I'm watching the photo more than I am the histogram. Maybe this is the wrong way to do it according to some who think more mathematically, but I like my way. The way that I learned about levels, in a nutshell, was to move the left and right sliders until they were nearer to their closest peak on the histogram. So, you would move the right slider a little further left if it wasn't directly under the furthest right peak (on the histogram). Do the same with the left slider. Then move around the middle one until it lookes like you want it. Of course, these are guidelines I got from a book, but they are good for general touch-ups. Hope this helps!

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6/3/2005 5:10:43 PM

Vince Broesch   When you go to levels, just click auto, and then look at where auto set them on each (RGB) channel. That will give you an idea where they should be set in general. They should be up to the edge of your data on the histogram. You can move them - you don't have to accept the position that auto set them at.
What you are doing is increasing the dynamic range for that color (channel). There are only 255 steps from white to black; in general, your data should stretch across that full range on each color channel. In general, you should not need to move the output; it should be full dynamic range.
There are exceptions, like for offset press you would want to limit your output to about 90 percent of the range.
A photo of snow would, of course, have a lot of pixels near white.

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6/5/2005 12:00:29 AM

Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
  It's best not to use auto and learn to use the eye droppers to set the blacks and whites.

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6/5/2005 1:02:49 AM

Scot Benton
BetterPhoto Member Since: 3/29/2005
  Hold down the Alt key (in Windows) while you adjust the sliders. It will show you where the ultimate whites and blacks are and how much.

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6/5/2005 2:27:07 PM


BetterPhoto Member
  ps is the best

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6/6/2005 9:09:37 AM

BetterPhoto Member Since: 5/28/2002
  Ed-or-whatever-his-next-name-will-be's bs is the best.

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6/6/2005 11:23:34 AM

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