Colours on WW2 aircraft are often a contentious issue. Different factories used different shades of paint at different times, particularly the Axis countries. The paint faded over time as well and the game alters the way colours look. Sometimes its a case of TLAR: "that looks about right".
Simmers Paintshop is a good site. I've also used the
IPMS Stockholm site at times, although this needs a screen capture utility to be useful.
There are various filters in paint programs you can use to get the "aged paint" effect. I do it another way though. First make sure one of the paint layers on the skin covers the entire painted surface of the plane. You can use this layer to select just the painted areas of the skin for weathering effects. The other colour layers are placed above this with portions of them erased.
Create a "paint ageing" layer. After selecting the painted areas move to this layer. Then select the airbrush tool. Give it a very wide spread but a very low density, say 255 pixels wide, but 1 or 2% density. Using some shade of grey or brown spray evenly over the whole skin. Then change to a different colour and repeat. I usually do about 3 or 4 colours with at least one quite dark and one quite light shade. The colours used depend on the colours beneath and where the plane was used (desert, at sea etc).
What you'll end up with is your skin covered in lots of randomly placed individual one pixel dots of several different shades of grey and brown. What you do next is gaussian blur these, 1 or 2 pixels usually works for me. Finally reduce the opacity of this layer until the effect is barely visible.
Material files in AH aren't useful for weathering. They just effect the overall way the skin reflects light, how shiny or matt it is for example. In other games you can use a map to make some bits of the skin like paint chips shine out against a matt paint. This needs a lot more video memory per skin however. This would be a problem in AH, where there are so many skins that can be on screen at one time. Here's a couple of threads on weathering:
Thread 1 Thread 2
