Here's how I quickly knock out some of the alternate color schemes for the GW photos of new marine releases. My version of PS is CS6 and is a bit old but it should work for most versions.
As an example, here's the rotating colors gif that I made using what I'm going to show you.
I always try to use Ultramarine pictures for this and I'll explain why a little further in, but for now, the first step will be to load up the Ultramarine pic in PS and you can see I have the Primaris Captain I used for my 16 color rotating gif.
Next you will see that I click on the Adjustment Layer icon and choose the Hue/Saturation option. If you are ever going to alter a picture in any way with an adjustment option such as Hue/Saturation, Levels, Curves, etc, you should always do it as an adjustment layer because this allows you go back and play with the options at a later time and it's not a permanent change to your image. You can simply hide the layer or delete it if you don't like the results.
After creating the Hue/Saturation adjustment layer, I click on the Master drop down and choose Blue so that when I play with the Hue slider, it will only affect the blue colors in the photo. The reason that Ultramarines work so well for this is that there is rarely much blue in the pictures other than their armor so you won't be changing anything but the color of the armor. If you chose the Yellow tones from the dropdown for example, the Hue slider would alter the color of the gold trim and decorations, the eyes, and the paper on the purity seal.
Here's what happens when I move the Hue slider with only the blue tones selected.
Pretty cool, huh? And that's pretty much it. The Saturation slider will decrease or increase the strength of the color in the image, and pushed all the way to the left (-100), it removes all the color. If you did this on the Master setting of that dropdown (affecting all the colors in the image), it would turn the entire image black & white.
To get some of the colors in the gif like the darker green of the Salamanders or the darker red of the Flesh Tearers, I used a combination of the Saturation and Lightness sliders to both desturate and darken the brighter red and green armor colors that precede them in the gif. To make the black armor, I pushed the Saturation and Lightness all the way to the left, and for the lighter grey armor, Saturation all the way to the left and Lightness all the way to the right.
There are some limitations to the colors you can get with this technique, and a good yellow color is hard to come by. The closest I could get to an Imperial Fists tone with just the Hue slider is the ochre color that precedes it in the gif and then I had to fiddle with the Saturation and Lightness sliders in tiny increments until I got it as close as I did. A pure white color is also not possible and the light grey color in the gif is as close as you can get.
Hope this helps anyone that wants to see what an alternate color would look like on a model!
Edited by Brother Chaplain Kage, 29 May 2017 - 09:52 AM.