Michael A. Stecker

Luminous Mask vs. Selective Levels/Curves

Test of Selective Levels/Curves in Photoshop



Selective Levels/Curves

Before: Shot with Canon A710IS at 6X zoom


After: Selective Levels applied to shadow areas





1. original photo
(by DrFogg)


2. Selective levels applied to blue sky, houses, bird and trunk plus cardboard in Adobe  Photoshop







3. Quick single photo/no mask technique
Simple lassos with 22 pixel feathers for midsection and lower trunk areas made.  Independently, a mid-level increase in curves made to brighten the selected areas in the two lower regions followed by levels adjustments for each.  For the sky I selected the blue area with Color
Range and did a 12 pixel feather.  A mid-level curve was pulled down to darken and a levels adjustment made to raise the contrast of the blue sky.  This is the "quick" method for adjusting brightness in selected areas of the photo.  Painting a mask is not required in this single photo technique.


4. General levels adjustment to entire image with slight brightening  (non-selective).






Rodolfo's image

The brightness range is too large and is not adequately covered by the exposure.  The highlights are grossly over exposed.  The histogram shows marked clipping (curve chopped off) of the highlights so the bright area can never be adequately seen.  Two exposures -- one for the trees and one for the bright grassy area can be taken and then blended in Adobe Photoshop which will result in a much better image.

I did do Selective (feathered Color Range) Levels on the bright areas in two stages which did help, but is still not optimal because the histogram was clipped in the highlights.  One could also use the "Shadow/Highlight" under Image Adjustment in Adobe Photoshop CS2 for similar results.


Original image with clipped histogram in the bright areas


Selective Levels applied to the overexposed bright areas