rstipe Loc: S. Florida

Are you a righty or lefty?

d2b2 Loc: Catonsville, Maryland, USA

I take my glasses off and use the diopter.

Vince68 Loc: Wappingers Falls, NY

I have a Nikon D800 and BBF is assigned to the AF-On Button, which on the D800 is just to the right of the AE-L/AF-L button. My thumb does not come anywhere near my glasses when looking through the viewfinder of my D800, and does not get in the way. Your D7100 only has an AE-L/AF-L button which is the button that should be assigned for BBF on your camera. Looking at a photo of the D7100 I would say it is probably a little bit to the left of where the AF-On button is on my D800, which may make it a little closer to the eyepiece of your camera. But looking at the photo of the back side of the D7100, it does not appear to me that your glasses should get in the way, especially if you are looking through the viewfinder with your right eye. That raise the question, which eye are you using to look through the viewfinder, as you did not specify that in your post. If you are using your left eye, then I can certainly see your glasses getting in the way, but using your right eye, it doesn't appear that they would get in the way of your finger.

DaveO Loc: Northeast CT

LOL!

Sorry. Having followed the thead I found a little humor. Guess you had to be there.

brooklyn-camera I Loc: Brooklyn, NY

You can purchase a different diopter for your camera, go B&H or ADORAMA.

HertzSone Loc: West of the Cascades

Depending on the op’s circumstances, would not a set of contact lenses eliminate the issue?

kenvan40

Thank you everyone for your comments and support. I inadvertently said finger when I meant thumb and as I am nearsighted the option to remove my glasses is not available to me. That being said it is awkward placing my Thumb between my glasses and viewfinder meaning it will be a detriment when I want to take a photo on the spur of the moment. For landscape it is no problem and I can work around it. I have programmed the Front lower button for focusing and it seems to be quite comfortable and works the same as the BBF. So now I will use the FBF or as I prefer, the FFB (front focus button).

dsmeltz Loc: Philadelphia

Congrats to the OP who found a work around from the helpful advice offered here!

Just a note to those who did not get the issue. The back AF button on the OP's camera is ridiculously close to the eye piece making it difficult to use. (Not all Nikon's have this problem)

The OP is very near sighted so getting a replacement diopter has limited value. When you use a replacement diopter and try to take a shot without your glasses, you lose the ability to keep both eyes on the action, if you are really nearsighted. Don't know about you all, but I look through the VF and my other eye simultaneously. It is very important in tracking elements in the scene. And not just for action. I want to know when a pedestrian, a subject or other item is moving into frame. If I do that without my glasses on, everything becomes a blur through my free eye. If you have not yet developed this both-eyes-open skill, you should really try it.

brooklyn-camera I Loc: Brooklyn, NY

Can get a replacement diopter thay even Helen Keller could take great photos, this coming from a guy who is blind as a bat without my glasses.

bobbygee

My left eye is dominant so I assigned a front button on my D500 to AF-On.
Check your camera and see if you can assign a button that won't smudge your glasses and still use "back button" focus on a front button.