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EF 75-300mm How to Focus at 300mm


Hi I have A canon rebel T3 with 75 to 300mm f/4 5.6 lens. I currently have it to 300mm . How do I get it to Focus? Because when I look in the eye piece it’s blurry 



What happens when you push the shutter half way?

Can you switch to MF and focus it?

Can you focus at other focal lengths?

It focuses it when I reduce from 300mm

When I switch it to MF it won’t let me focus at 300mm


"Because when I look in the eye piece it’s blurry"


What you are saying is it is blurry at only 300mm FL setting? All other FL are OK?


I don't remember if the Rebel T3 has a diopter adjustment but if it does it is probably not adjusted to your eye.

EOS 1DX and 1D Mk IV and several lenses!

Yes it’s blurry at 300. When I reduce it the focus get more clear 


What do you mean by "it won't let me focus?" if the focus ring does not turn in manual focus mode at 300 mm there is some odd mechanical problem with the lens.

You are turning the focusing ring, right?


Yes . But how do I leave it at 300mm and have it focus 

"there is some odd mechanical problem with the lens."

You need to get the lens fixed. But a 75-300 is not worth fixing. Save your money for an EF 70-300, a much better lens.

I have a canon EF 75-300mm f/4 5.5 lll telephoto zoom lens

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