Levels

Levels

Correcting colour casts and contrast. The destructive Method.

After scanning, or downloading from a camera, the first task should be to correct the contrast. The contrast control is a little crude so Levels or Curves give you much more control.

Use CMD and L to get the levels window. You will see that the histogram shows that there is very little at both the black and the white ends of the graph. Hold the Alt key down and select the white slider, you will see the screen turn black. Now move the slider to the left until the highlight areas start to show through. If any go white, they will appear burnt out on the image. Repeat the process with the black slider, this time the screen goes white. Repeat as necessary until the contrast is acceptable.

Select the centre eye dropper, this is mid grey. You now need to find an area in the image that you wish to appear as a neutral grey. Click on the area and you will see the colour balance change. The program uses the area you have selected as a reference and alters the 

colours to balance this to grey.

Non Destructive

To avoid permanently altering the image use a Levels adjustment layer.