@Paul - Thank you for your comments and I am glad that you found the photos pleasing. We've experimented some with outdoor photos (weather permitting) and have found that a bright overcast day results in the best pictures. We believe that that is because the light in general, under those conditions, is more uniform. Too sunny and you end up with harsh shadows.
@Eddy - Nosey fellow, aren't you!
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Wnat me to divulge all the trade secrets.
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Seriously though, in order of the questions asked:
-Base colour NATO Green and black pre-shading were done using a single action, siphon feed Paasche Model H airbrush at 25 PSI. The NATO black and red brown were sprayed using an Iwata Eclipse HP-CS.
-All paints used were Tamiya and I also used that brand's thinner. The thinner is unique as it also contains an "extender" in it's formulation. The extender makes the paint more "watery" and less prone to dry in the air before hitting the model. Airbrush pressure for the camo was 12 - 15 PSI.
-All colours had approximately 10% to 15% white added to compensate for scale effect. It's pretty much a case of mix until it looks right.
Cheers,
Jan