1. Open the image with red eye problem. Below you will see an example image with a red eye.
2. Now we have to de-saturate the red pupil part in the image. First we have to select the pupil with the 'Elliptical Marquee Tool (M)'. Make a circular selection round the pupil.
3. Then from the main menu select 'Image -> Adjustment -> Desaturate' to desaturate the selection above, this last action turns black and white the selection. Next image shows the result of this step.
4. Create a new layer with this selection or just pressing Ctrl + J in the keyboard.
5. Choose the 'Brush Tool (B)', set the mode to 'Soft Light' and set the 'Opacity' to 50%.
6. In this final step you have to select a color related to the color of the eye, and draw over the layer created in the step 4 until you have obtained a realistic result. Next image shows a final result of this tutorial.






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