The photo of the gun on the foredeck is the automatic 6pdr gun the Dog Boats were armed with later in the War. There are other close up shots of this gun available on the IWM web site
. It definitely would not have been taken in combat as all personnel would be closed up at their stations during any action. The second photo shows German E-Boats, so this must be the German forces that were gathered at Tagliamento in the Northern Adriatic in late April 1945 and which surrendered there to a force of three Dog Boats, MTBs 634, 651 and 670, who escorted them back to the CF base, then at Ancona in Italy. Certain of the E-boats had broken away from Tagliamento to return to their own base at Pola to pick up their base staff there, to prevent them falling into the hands of the Yugoslavian Partisans, and then made their own way to Ancona to surrender. The incident is recorded by Len Reynolds at the very end of his book MGB 658
in which he relates having been absent from his own boat, having to attend as a witness at a Courts Marshall on Malta, but that the E-Boats had been spotted in their approach to Ancona, and 658 with others had roared out of harbour to meet them and escort them in. So depending on which E-boats these are, this could have been taken from 658, or it may have been one of the other Dog Boats at Tagliamento, photos having been shared among crew.
P.S in the third photo, this looks like a stern view of the Dog Boat, stern on to an E-Boat, with the aft 6pdr turned to starboard, and one of the Officers or a Petty Officer temporarily manning the midship Oerlikon turned to port, this possibly to indicate the boat will not fire, in response to the E-Boats which were said to have had their guns in a vertically elevated position to indicate the same, whilst flying a white flag.