I have a MacBook Air running 10.12.1 Sierra. Loaded a lot of photos into Photos app. When I scroll through them full size, using the arrow keys, some of the photos look blurry UNTIL photoI zoom in and then zoom out - then it's clear and sharp. It's a problem because I'm going through them specifically to delete bad ones and I might delete a photo that's actually sharp! Weird - anyone else have this problem? Not sure it happens with every photo but it happens with enough of them to prompt this question. 
Thanks!
Andrew
	
		
			
		
		
	
				
			Thanks!
Andrew