Not standard schemes were due to many types of repainting.
The use of field made camouflaged started at the war outbreak, usually on the base of the old solid green painting.
In some cases the field camo was very similar to the factory applied one, ie large bands of dark green or black.
Other aircraft were painted in more fanciful way, forthemost with thin mottling or striping of black on a green base; many photos exist of such arrangement, but they show forthemost the aircraft in only a partial way.
Many standard green/dark green MiG-3s were overpainted with black bands, mottles or sections; this could have been due both to a will to improve the two-shades camo, both to repairs. Perhaps the black paint was easier to be found on the field than the dark green one.
Sometimes the base camo was improved with the application of a lighter paint, that could have been light grey or sand.
 
 

no. 42 of 7 IAP,  Leningrad front, October 1941	unknown unit, possibly 401 IAP	n.9 of 38 PAE,  Moscow front, late 1941.
aircraft of Lt.Baikov of 34 IAP, Moscow front, 1941	unknown unit	unknown unit

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