Many thanks Bora and Joel!
Joel,
I have had better pre-shading results when placing the pre-shading in random panel lines, if the pre-shading is too uniform the end result could be the bottom of the model looking almost like a quilt.
The same goes for panel line washes, I don't usually care for high contrasting oil color washes (like black) and have found using darker shades of the same color the panel line wash is going into is pleasing to the eyes, black will still be used on mostly just control surface gaps and near engine cowls.
When I paint the upper surface colors on my aircraft models I usually paint the wings and tail planes first, this way I have a safe place to hang onto the model whilst painting so I don't leave fingerprints in wet paint.
This 109 will be getting more weathering than the Revell 109 I finished a couple weeks ago so I will go with some subtle paint fading on it.
After a thin base coat of RLM 75 was sprayed on I added some highlights in a highly lightened version of RLM 75.
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Then some contrasting darkened RLM 75 was sprayed on for some pre-shading.
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And below a base coat of thin RLM 75 was sprayed on to tone down the weathering effects. I was trying to get a patchy sun faded/worn look to the paint and I think I achieved this.
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Matrixone