novoflex tolerances

R

Rob Alexander

New member
Hi,

I've just bought a few lenses to use with my AF101 - Tokina 11-16, Tamron 17-50 & Tamron 70-200.

The AF & novoflex I bought second hand. With the 50mm & 35mm Nikkors I have no problems but mounting the Tokina & 17-50 Tamron I'm noticing a little play in the mount that results in a small rotation of the lens when I change focal length which in turn affects the aperture and (sometimes) the image's horizontal position.

Is this likely to be the fault of the adapter or the lenses not fitting quite tightly enough. I don't have a Nikon DSLR to try them with.

Many thanks for your thoughts in advance,
Rob
 
I have a Tamron 17-50 with the same set up. Novoflex and AF100. I haven't experienced any of your problems. Try going into your local pro video store and test out a new Novoflex and see if the problem persist.

Just to be clear we are talking about the non VC tamron right?
 
Rotation (play) in the adaptor cant affect the aperture.

I would expect that the horizontal shift is caused by play inside the lens due to internal wear and basic engineering of the lenses. eg plastic parts
 
Couldn't the expected result (or consistentcy) of the aperture be effected by play in the adapter if there were light leaks?
I read that somewhere so forgive me if that's wrong . . .
 
I know what you are talking about.
I got the same effect on one of my cheap China adapters.
Sorry to see, that the expensive adapters are no better (was eyeballing a Novoflex).

I have 35 bucks adapters that are snug as can be, and I have more expensive ones that have leaks, wobble or change aperture.
There is a little lever, that works the iris in the lens. If you got play in the mount, you face tis kind of effects.

Frank
 
It works with the nikons but not the off brand lenses.. go figure, the problem is the poor tols of the off brand lenses no doubt

now a bit of electrical tape between lens and adapter can work wonders, thats why have one adapter per lens

S
 
Rob,

My setup is similar to yours and I am experiencing the same aperture shift with my Tokina 11-16 and 16-50. I even went so far as to purchase a second adapter from MTF Services. The Tokinas do the same thing on the MFT adapter. My Nikons are rock solid on both adapters. I guess thats all part of what you get for the money.
 
Thanks for all the thoughts, yes as mentioned by Frank and Derek the rotation moves the aperture control lever on the lens thus altering the exposure. For the time being I loosened the face of the novoflex and cut thin plastic (from a drinks bottle) to shim it and then tightened the face plate back down, this now gives a nice snug fit. Given that the lens bodies reach deeper into the adapter I don't think I'll get any light leaking in and on first test this appears to work - I'll probably improve this solution by fashioning a proper gasket to sit in between the adapter body and its face plate.

Rob
 
I too have a Tokina 11-16 with a Novoflex Nikon-M4/3 adapter, and I can confirm there is play between both the lens/adapter and adapter/body (GH1). There is also sometimes a slight exposure shift when the lens moves, but seems more likely to occur when stopped down a bit rather than wide open.
A quick examination shows that my problem is caused by the adapter locking pin being just slightly too narrow for the lens' locking groove, causing the slight play. Also it seems the adapter's rear locking hole is slightly too wide for the M4/3 mount pin, causing the similar problem on the opposite side!
Quite honestly I expected these Novoflex adapters to be tighter. A pretty poor show. Like Frank, I have other adapters that cost a lot less than this one and are a lot more snug.

Rob, I would excercise some caution with adding even thin spacing materials between a lens and a precision-made adapter, as you are effectively shimming the mount - which will cause a slight shift in the plane of focus. This difference may seldom show up clearly in regular use, but could cause a loss of infinity focus.
But... I think the the 11-16 may focus past infinity, as the barrel definitely turns past the ∞ symbol on my copy. So you may be OK there. But best to check if you haven't already done so.

A quick solution of my own is to cut very thin strips (~3mm wide) of electrical tape and lay a double layer of them around the central groove in the 11-16 lens mount and around the back of the Novoflex adapter, which also has a similar groove. Adding some extra thickness of tape down the side walls of the pin grooves will also help.
This very thin "gasket" of tape works just about flush with the metal, and gives a bit of springy grip, tightening the interfaces. The play on both sides of the adapter is minimal now, and I haven't noticed the aperture shift again.
IMGP6797.jpg
Has anyone else tried this?
 
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