How to test for front & back focus.

[TLR-330]

Hi,

I got a new toy (Tokina 11-20mm for a Nikon D7200) and I would like to test it for any possible focus problems. I have really just opened the box so I have no reason to suspect a problem but for what I have read about these lenses in a couple of instances.

Any pointers to a testing procedure please? Although I am really a newbie to autofocus (as my handle may suggest) I get the idea of what the problem is, so how do I test for it just in case I have to reject the lens.

Thank you & sincere apologies if the same question has been asked thousands of times. Searching the forum did not bring up any clear answers.

 

[rob-nikon]

i would suggest using it first rather than testing it. If there is a problem you should soon notice it, why go looking for a problem that most likely isn't there. I'm guessing you have got this for landscapes so it's going to be used at smaller apertures (large DoF). It's unlikely with a large DoF and fo using further away that the focus will be out by much as DoF is so large. It's more apparent with close up subjects at wide apertures.

Reading your OP again I think you are talking about whether it's soft when focused. This should be apparent when in use. If you really want to test it just google 'how to test a lens' or 'testing a lens', there are plenty websites with suggestions. I often use photographylife.com reviews as they are quite good. They suggest how to test a lens and how to check front/back focus in the link below. Don't forget it sometimes may not be the lens, it could be the camera. I nearly sold a 70-200 because it back focuses very badly on my d7000, when I swapped to a d7100 it was perfect. It was definitely the d7000 as other lenses were not right and it was a known issue too.

https://photographylife.com/things-to-do-after-buying-a-new-lens

 

[littleted]

If you struggle with this tuning, i use Focal Pro by Reikan, its a semi automated process that actually tests your lens and then tells you where to put the fine tuning marker to. i use it with all my Lens and my D500, the D500 does have Auto fine tune anyway but the focal stuff is a lot more thorough in the way it does it...

Good luck..