I dont know what paint to use the humbrol nr 67 panzer grey ore the tamiya nr TS 4 german grey. Can somebody tell me what collor is the best of these two
I presume the colour you are looking for is RAL 7021, for which several sites seem to think that Humbrol 67 is a good match.
Is TS-4 the same as XF-63 ? That (XF-63) is the Tamiya colour which people seem to equate to RAL7021.
Even when you have picked your colour, you then get into the debate as to whether you need to lighten it to counter the effect of the reduced scale of the model - see the recent thread in the Panzer III forum.
In the end it usually comes down to personal choice.
Personally, it seems to me that the really rusted and faded tanks werer the ones that had been destroyed and abandoned, perhaps after the war. Just my opinion though.
Compared to the original RAL 7021 both samples are way too light.
The original paint was much darker and varied from almost full black to a very dark grey with a touch of blue, depending on the light conditions (indoors or sunlight).
The Humbrol colour with some additional black could do the trick for a scaled model.