35/1.4 issue focusing on infinity, need advise

[alexc]

Advertisement (gone after registration)

I am traveling with m9. One of the lenses (summilux 35/1.4' two year old) does not focus on infinity. Images in the patch do not come together. This is something new. When I load images to the iPad everything seems to be in focus.

 

Any input will be greatly appreciated

[Marty]

Sounds like the lens focuses fine but the rangefinder coupling is off. You say one of the lenses, but have you tried the infinity focus on other lenses recently? I had the same problem and needed to have the rangefinder adjusted; afterwards everything was ok again. Any idea when the problem started?

[alexc]

This the first thing I did, checked other lenses, no problems, just this lens.

[dpattinson]

This the first thing I did, checked other lenses, no problems, just this lens.

 

You should probably check close (2 meter) focus at f1.4 and see if the lens is off at that distance. You can't do much about it while traveling if it is off, but once you know by how much you can compensate when shooting (or just shoot stopped down).

 

RF coupling doesn't matter at infinity, but if it is off at closer distances you could end up with a lot of misfocused shots. Might not be that easy to see on the ipad without shooting jpeg and zooming in.

[djs]

I had a problem with the same lens on my M9.

The focus patch was spot on at infinity and all my other lenses were fine, but the 35/1.4 was off when set to infinity.

I then took about half a dozen exposures - the first with lens adjusted to the infinity end stop, then each subsequent exposure with the focus ring moved slightly further back from the end stop. (Ignore the patch)

When these exposures were viewed on the computer, one of them was found to be in sharp focus, but not the first one taken (at the infinity stop). Clearly then when the focus ring reached the end stop, it had "overshot" infinity. (Focus at the minimum stop was spot on.)

 

Edit - Note that the test exposures were made with lens wide open, for minimum depth of field.

 

I returned the lens to Milton Keynes UK, who in turn sent it on vacation to Germany for re-adjustment. Took about 5 weeks!

 

Hope this is of some help.

 

 

Donald.

[alexc]

Donald,

 

Thank you for the input.

I tried many exposes with different apertures. Everything seems to be in place. Having said this I am viewing images on my iPad and do not have access to good monitor. If everything will be fine on high resolution monitor do I ignore the issue or address it to Leica?

[djs]

Advertisement (gone after registration)

It would be better if you could determine exactly what the problem is first.

You said that the focusing patch would not line up at infinity. On this lens only, or with all lenses? If this lens only, then you appear to have a problem with this lens to body interface.

 

Also, better to view results on a large monitor.

 

Is your image in focus (at infinity) if the lens focus ring is against the infinity end stop?

 

Once you have determined exactly where the problem is, how to deal with it will be apparent.

 

 

Good luck,

 

Donald.

[JWW]

I had the same type of problem with a Summicron. It helped to check at wide open and also by taking comparison pictures using another known good lens. This showed a defocusing at infinity so I sent it to DAG who repaired it.