Letters From Home

SPOILER

The clue above the entry box means to look at the name of the hotel: datoname hotel = day to name.

So take the day of the month given in the post marks, and then take the country name on the stamps. Sometimes you'll have to figure out the country.

Apply the number to the name like this:

Nov 7 United States = United States = S

You get "St Paul's Cathedral".

The hint from the London projection [1] is "Photographer"

Answer: HERBERT MASON . He took the photograph of the 1940 bombing of St Paul's Cathedral in London.

SPOILER

Working top to bottom, left to right gives the following:

Nov 7 - United States

Apr 9 - Great Britain

May 1 - Poland

Dec 2 - Japan

Jan 2 - Bulgaria

Jul 8 - Switzerland

Mar 2 - Estonia

Feb 1 - China

Jun 7 - Romania

Oct 2 - Italy

Aug 1 - Hong Kong

Sep 4 - Argentina

Nov 10 - New Zealand

Jun 3 - Norway

Apr 6 - Canada

May 7 - Australia