Crisp to Blurry iPhoto pictures

When I import photos from my iPhone5 to iPhoto, the pictures are crisp for a millisecond then become more blurry. This has been a consistent problem for the past few months, but did not occur until I (against my will) upgraded to OS 10.7.5.

I have also seen numerous other posts in various forums describing the same problem, with no solution. It is ridiculous. The camera is clearly taking higher-quality pictures, iPhoto is clearly uploading it correctly, if only for less than a second. I'm getting afraid to delete photos from my phone because I don't know how to fix this problem and I don't want to lose their higher quality.