Quality of .gif output from Photoshop
I'm trying to output a .gif from Photoshop (CS6) and have run into some difficulty with the quality it is producing. Ideally, each image should resemble these stills - 1, 2 and 3 which are crisp and clear, but as a .gif file (especially on the second image), the depth and colours are removed, resulting in a splotchy image animation...
You're experiencing dithering due to the color reduction of the GIF color table. Gif images can only contain a maximum of 256 colors. There's really not a great deal you can do about it.
You are asking the gif format to support smooth color, which it doesn't. The best you can do is experiment with the dithering options in the Save for Web window. However, you are never going to get a smooth color photograph when using the gif format.