Larger photo with soldiers and officers gathered in front of a tent. Several stretchers in photo, and a man with armband, so assuming military field hospital?
Some soldiers wearing Stahlhelm helmets, others field caps. This would date it to 1916 or later.
Needs further investigation
Pencil ‘8552’ on back.
Printed on thicker paper
12 x 16.50 cm
(Red text is an electronic watermark that is not physically part of the photo for sale)