Looks to me like he is trying to get the photos tossed out because of possible distortion during the enlargement process.
It goes, I believe, to the elevation of the muzzle of the rifle. Some photos may be distorted so as to show the barrel of the gun is higher than it really was. If the barrel was not pointing to the ground as the defense states, the ADA makes the claim that the gun was pointed at the attacker.
sounds like the prosicution has doctored some images... PHOTOSHOPED THE EVIDENCE.