Deepu Chand R

How to find the correct colors to use in design? (i.e, colors for nature, Engineering, Automobiles etc) is there any rules for that?

The process of finding the most relevant colors of a photo is called Color quantization - there are many different algorithms to do that some of which are aiming to be fast, some which try to get the best fit. But since you ask this in "Photoshop Techniques" you are probably more interested in a hands-on approach: In Photoshop the easiest way is to select Image -> Mode -> Indexed Color then in the following popup you select what algorithm should be used for the color reduction and how many colors you want to reduce the image to. A good choice is one of the "Local: Perceptual/Selective/Adaptive" and if you want to use the colors as a color scheme for a website to pick a rather low number of colors like 5 to 8. Once you have converted the image to Index Colors you can see the color palette by opening Image -> Mode -> Color Table. That window also allows you to save the colors as an ACT palette file. Keep in mind:- 1. Convert your photograph from RGB to Index Color Mode and choose your settings. 2. Go to Image > Mode > Color Table to create your color table. 3. Save the color table as ASE rather than ACT file. This way, you can use it for any Adobe product rather than just Photoshop.