What color brown was the original SA/SS brownshirt?

[Dimitrov2012]

I'm looking for information on the original SA brownshirt aka the (Rossbach bought) 'Lettow Shirt' (1924-1929c) It was worn by Hitler, Hess, Himmler and many others attending the 1927 Reichsparteitag. It was even worn by Horst Wessel

Hitler wearing the shirt in a 1926 Hoffmann test photo

1926 ah1 (2).jpg (20.49 KiB) Viewed 731 times

Here is Hitler wearing the shirt with Goebbels at the 1927 Reichsparteitag

1927 tumblr_nqinhhiHhA1rknukao1_500.jpg (52.19 KiB) Viewed 731 times

Also from the 1927 RPT: Hess, Graf, Himmler, Hitler, and others wearing der shirt

1927 Nurnberg5.jpg (52.73 KiB) Viewed 731 times

Very specifically, I'm looking to locate one of these rare shirts , from a private
collection if possible, to answer a few basic questions:

Photos show it to be a rather dark brown, with pearlescent buttons, but what shade
of brown was it?

What was the shirts material? It appears to be rather course in the photos. denim?
cotton? gabardine? It also looked to have a sheen to it. what does it look like to you?

What was the reason for the unique upper sleeve cut? Do you think it was meant to
adjust the length of the sleeves?

Hand colored photos and a few paintings are the only color references which could
be found.

here are a few:

This appears to be a painting made from a 1926 Hoffmann photo

1926 CLEAR truth-woman-ah-art28.jpg (68.96 KiB) Viewed 731 times

This was a hand-colored cigarette card also made from the same 1926 photo, but with a different shade of brown.

1926c Hitler mystery shirt hand painted.jpg (82.02 KiB) Viewed 731 times

Would be very grateful for any help to locate a collector who might own one in
private collection.

Also would appreciate comments from those knowledgeable about uniforms from the kampfzeit period or anyone else wanting to assist in this challenge

Please post any photos of this shirt that you might have here, to aid in the discussion

[von thoma]

but what shade of brown was it?

I would say it's a "chestnut" or "sienna" brown colour.
Later the NSDAP shirts adopted a tone more clear, "bronze" or "cooper" brown.

[von thoma]

"cooper brown"

It sounds like something for keeping birds....
I meant "copper brown".