You might check to make sure that your camera is set for close objects...
I believe your tin was made by the Metal Box Company, Limited of London.
Here is the logo of the English firm stamped on a 1941 mess tin.
Here it is on a 1943 megaphone.
Here is another similar stamp for the Indian branch of the Metal Box Company, Limited (of Bombay or Calcutta) on an Indian-made Pattern 1937 strap.
Lastly, here is the Indian firm stamped on some Indian-made mess tins.