1942 panzer colour

[V]

All chemical films are however colour balanced, that is why the person in charge of the colour balance gets their name in the credits.

Possibly apocryphal story: when the first colour films of photographs taken at Peyto Lake in Canada were sent off for processing, they were returned with an apology that there was evidently an issue with the film, as they could not get a colour positive image with believable colours. This was due to the distinct and unnatural looking  turquoise colour of the water.
https://en.m.wikipedia.org/wiki/Peyto_Lake
And yes, it is that colour.

They certainly are all colour balanced, and the chemicals used for development can effect colouration of the negative and the films original dyes can impart a hue, in regards Agfa stock of the 1930s it seems to have a red hue to it on occasion. They also degrade over time so that with restored slide transparency the restorer has a degree of artistic influence on the final product.

However colour balancing would not take that StuG from grey to yellow while keeping the rest of the scene correct, but I do agree the colours across that photo, and others of the period, would likely be a little different in real life, as we see today even with digital cameras. But on the whole, it remains a very good period rendition especially of German Field Grey uniforms of the period.

[V]

Thank you V for that information I think it will send some rivet counters into a swoon . I plan on building a collection just for Stalingrad so it will give me something to think about.

It's never an exact science, especially with the Germans, but some historians do take the German orders on camouflage of Panzers as an absolute, when I'm personally not sure on that.

The change to Panzer Grey plain, from the red/brown of early war is dated June 1940. However there are colour images from Poland 1939 that seem to show tanks and other vehicles in plain grey.

This isn't unlikely. Factory production could be speeded up by the deletion of one colour in a factory applied scheme. When preparing new vehicles for an upcoming offensive it seems likely this step would be taken to increase production output. It's also anecdotally stated that the June 1940 order to move to plain grey was merely officially recognising a practice already underway at the factories due to the need for rapid production.

Of course part of the issue with black and white.in 1940 is that Rot Braun looks the same as Panzer Grey in monochrome. Only in a few.pictures cant the two tone camo be seen, but on colour transparency film we can see both Rot Braun/Panzer Grey and plain grey in use.

My personal view is that the Germans were never as exact and precise as we may wish to stereotypically assume of the Prussian Military Machine. All manner of variations and trials were also tested and conducted, the sheer variety of things the German military tried and did is astonishing and often futile and a drain on resources. Which to me makes it all the  more exciting for modellers and wargamers.