Sometimes, when my brother sends me emails with attached photos from his iPhone 6, the photos are about 3 or 4 times the size of my screen. It's not always but is quite often. I'm not sure if the problem is on his end or my end - I can't find any settings or preferences to address this. I've tried sending myself photos from my iPhone 6 specifying the photos as small, medium or large - they all show up the same size on my MacBook screen. I'm on a MacBook Pro running 10.10.5 Yosemite and my email is Gmail. Any help greatly appreciated.