Akubra
I think the aircraft is an Avro 504N and the camera is mounted above the tailplane.
Flap40
I appreciate your question, the figure quoted came from the Flight article, the article also stated that the engine was a Gypsy Major. I note that A J Jackson in his book De Havilland Aircraft since 1909 states the Tigermoth DH 82C had a range of 275 miles so whether this aircraft had a larger fuel tank I do not know