Today is the day of colour casting… What can you do if you have an image with colour cast, for example a scan of an old photograph? Is there anything you cna do to get rid of it? Of course you can! 🙂
This technique works really well on the images that have colour cast like old scanned photographs as an example.
We’ll start by finding the Shadows and Highlights in the image to find real blacks and whites. We will be using Color Sampler Tool and Threshold Adjustment. Here is our Before and After:
We’ll start by Selecting Color Sampler Tool and in the Options Bar choosing 3 by 3 Average.
We will need Info Panel so make sure it is open. If it is not, go to Window -> Info to open it. Info Panel will display colour values for pixels and will give us some important information.
Let’s add the Threshold Adjustment Layer:
In the Threshold Adjustment window, we will set Shadows and Highlights. Let’s start by setting Shadows first – drag the slider in the Threshold dialog box to the left until everything goes white, then start slowly dragging it to the right until some black pixels start showing through.
Now Shift-Click on the image (on the black area) to set sampling point. A new sampling point with number 1 will appear.
Next, do the same in the opposite direction – move the slider to the right, look for the white pixels and add a sampling point number 2.
If you look into the Info Panel, the numbers show you if any of the channels are dominant creating tint. To remove the tint, go to the Levels adjustment, select Shadows Eyedropper and click on the 1st sampling point. Next, select Highlights Eyedropper and click on the 2nd sampling point.
Select OK to accept changes and you’re done! 🙂