I updated to 10.10.3 this morning. After the update, I find that Preview will not display jpgs in 7360x4912 size (D810) if those jpgs were exported from LR 5.7, using the same LR settings I've been using for many months. The image flashes briefly (maybe a second) and is then replaced by background, which seems to scroll up. If I ask for a thumbnail I get one. But I can't do anything with it. If I use Preview on a 7260x4912 NEF -- no problem. If I take the 7360x4912 jpg into Photoshop and do nothing but write it back out again, Preview will open it. The same is true for a NEF that I bring into PS. I took a Sony RX100 jpg into LR, sized it to 7360x4912 for export, and Preview failed. At 7220 it fails. At 7018 it doesn't. At 7019 it does. It seems to be a LR--Preview collision of some kind, but what could that be? I'm baffled.