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So I was taking pictures last night and I turned off the camera and then turned it on again to take more and all of a sudden the squares won't go red anymore to focus. I tried on AV and manual and the squares just won't focus any more.. Anyone know h...
I have a Canon EOS 80D. I also have two flashes (4300EX 3-RT) and (270EX 2). Does anyone know if there was a way I can get the two flashes to go off while I take a picture and the flash on camera would stay off.
What's the difference between a sigma 18-35 1.8 and a sigma 18-35 2.8? And will they both work with my Canon t3 rebel? 
i currently have a canon t3 rebel with a 50mm lense and a stock 18-55 lense. im looking to get a good another lense like the 18-35. anyone have any thoughts on this and where can i get one for a good price because they are a little pricey?