The following model had a somewhat unlucky history. As you may see, it has a pretty uneven paint distribution. What happened is that I dropped it by mistake 4 meters from the balcony (where I spray the undercoat) in the garden below. So wet undercoat + mud equals something else than good.
On the positive side, I've used it to experiment with some color schemes and painting techniques, the latest being the EYES.
I wanted to create a new helmet pattern for my army, since the other marine squads need to stand out from the sternguard placeholder I've finished. I tried yellow faceplates , I tried gold faceplates, and settled for black.
However, the regular red eyes were not good enough against a black background, so, after several tries I came up with this look (don't mind the paint splats, he's my walking test pallet)
How this came to be:
1) Painted the eye sockets with Mechrite Red
2) Painted almost 3 quarters of the eye socket from front to back with Blood Red.
3) Painted the first half from front to back with Blazing Orange
4) Added a dot of Sunburst Yellow
5) Filled the eye sockets with a hefty amount of Baal Red wash. This last step provided an internal outline for the eye socket as well as blended the colors together.
I've made a rough sketch of that below. Note that the colors I've used are the RGB values from GW's paint chart.
The good thing about very dark backgrounds is that you don't have to worry about overflowing paint from detail slots, such as eyes. Instead, you can use the extra paint outside to create a glow effect. This is done by using a wash corresponding to one of the colors (background, or overflowing foreground) as it will blend one color with another.