Nikon EDG I diopter drift solution (1 Viewer)

Hi all, this is my very first post in this forum.

I am a binocular geek. Recently, I purchased a used EDG I (10x42) from eBay. The optics and everything are outstanding (in fact the best among all binos I have ever used including Swaro, Leica, Zeiss). However, as mentioned by others, it is suffering from slight diopter drift. I investigated the problem and found a simple fix, which I want to share here.

The reason of the problem lies in the fact that diameters of the focus knob and the diopter control are too close. When the focus knob is turned, it easily touches the diopter (especially when one exert larger pressure on the focus knob). Since the diopter control is super smooth, it will move easily with the focus knob even when the "touch" of the two is very slight (first picture).

I found there is a small groove between the diopter control and the inner circular base of the knob (second picture). I found a very usual paper clip with rubber shielding and cut out a section of about 1 cm long (remove the metal wire inside. Just take the rubber shield) (third picture). Then I used the tiniest screw driver (fourth picture) to squeeze the rubber section into the groove (the white line inside the groove shown in the second picture).

The rubber section increased the friction of the diopter control, so it cannot be turned so easily. Now, the diopter drift problem is gone. No matter how you turn the focus knob, the diopter stays in the original position (unless you change it yourself). A simple, harmless and cheap fix.

Hope this help to anyone who need it.

Albert Tsang (Hong Kong)

Is there any chance the rubber could work itself out of the groove in regular use?

No, it won't slip out easily. In fact, I have tried other softer material (a piece of thin leather string) and that one worked out very easily. The rubber is stiff enough and it will stay in the groove.

Albert Tsang (Hong Kong)

akltsang said:

No, it won't slip out easily. In fact, I have tried other softer material (a piece of thin leather string) and that one worked out very easily. The rubber is stiff enough and it will stay in the groove.

Albert Tsang (Hong Kong)

Click to expand...

Albert

Excellent analysis and solution.

Patent it and sell it to Nikon

Lee

That's a heck of a first post!

Gotta agree. If that truly does fix the issue then I would be willing to bet that there are a lot of very intelligent people shaking their heads right now......

akltsang said:

No, it won't slip out easily. In fact, I have tried other softer material (a piece of thin leather string) and that one worked out very easily. The rubber is stiff enough and it will stay in the groove.

Albert Tsang (Hong Kong)

Click to expand...

Albert,
I tried that very same technique on my 8x32 EDG I about a year ago. I did not use the same material you did but instead used a sliver of closed cell foam which I forced into that groove. It only slowed the slipping diopter down but didn't stop it. Your material looks like it could be the answer.
Interestingly, I just checked my 7x42 EDG II and that gap or groove is closed. No room to force anything in there. I have not experienced any slippage at all in the four months I've used this bin. I wonder if the closer tolerances in the diopter/focus mechanism are the solution Nikon came up with to solve the chronic diopter issue on the EDG.? Didn't Mike Frieberg say that Nikon was "gradually tightening things down" a while back?
Thanks for sharing!

Tom

I just looked at the focus knob on my 10 x 32 EDG I. I've had it for over 2 years now. That gap or groove next to my diopter is tight and close and my setting remains where I originally set it. It doesn't look like the blade of that tiny screwdriver would fit into it at all.

There is one very minor problem with it though. The corrugated circular rubber band that covers the focus wheel has stretched somewhat. I understand that has been corrected by using a new band that is supported with fine steel mesh.

Bob

I wish someone would try my fix and see if it works only for my unit or for most other older EDG I.

I think Nikon can fix the problem very easily. They may simply make the diopter control slightly smaller (so it won't touch the focus knob) and add more friction to it internally. I dropped an email to Nikon today (without asking for patent fee!). Just hoping that will make them to improve this terrific (in all other aspects) binos.

My regret is I cannot find a paper clip with black rubber. That will better match the colour of the EDG.:-O

Great solution! Most certainly the most unique one we have seen yet. Nikon has corrected this problem (best case scenario), but there are people out there who still own the EDG 1. Great advice and thanks for sharing with everyone. I will make sure Nikon sees this.

All the best,
Mike Freiberg
Nikon Birding Market Specialist