28mm Ultron 19.9: Backfocus or shifting

[riceman]

Hi,


it is possible, that my old Ultron 28mm 1.9 has a back focus on medium distance and at infinity? at 0,7 to 2 meter with f 1.9 it focuses perfect, at 5 meters or at infinity it is very soft and it seems that the focus is off...


is that possible? is it focus shift?


*help*

thx and regards
marc

 

[isorgb]

Yes, I think it is possible.
When I used Ultron 28/1.9 on R-D1 I noticed that medium distance is liittle soft. Tests are not my big experience and I have not test, but some pictures are back focus.
I don't know why and I don't know how you can service it.
I would like to hear how check and service this problem myself 😉

I don't try this lens on M8, I use it, but not especially for check this issue. For me picture is good (with something special) or not and I don't have good from M8 yet (for me of course).

 

[Benjamin Marks]

I think the lens is a little soft wide open. But my version doesn't back focus or focus shift. I would send it to DAG for adjustment.

Ben

[Edit: you might want to check that the RF is properly adjusted too. Is this the only lens that gives you a problem?]

 

[riceman]

thx for your fast responste.

who is DAG? 🙂

 

[ferider]

This sounds wrong.

If the camera and adapter are OK (check with other lenses), your Ultron is faulty.

Roland.

 

[isorgb]

Hmm! riceman!
What camera? M or LTM? Maybe you have M adapter with "adventure"?

 

[Benjamin Marks]

Don Goldberg. USA. If you are in Austria, there may be someone closer who has these skills. I don't know European repair folks. Don can be reached at the following:

Don Goldberg <dagcam@chorus.net>

DAG Camera Repair,
2128 Vintage Dr Oregon, Wi 53575 USA

He has worked on any number of my lenses, particularly adjusting a set after my M8 purchase several years ago.

 

[riceman]

Thanks again for your replies. The last days a local repair guy. He looked at the rangefinder of the M8 and told me that it is ok (my 50mm focuses perfect)

Then he tried to adjust the Ultron, but now it still off.
Sometimes I think I have a backfocus and decentration too. But only at medium distance and infinity.


Look at this two sample pics.
First is about 2 meters away and sharp where it should be (at the big white bird **** line )
The second one is at 20 meter/near to infinity, focussed at the park bench. But it is sharp only at the left side and 5 meters behind....

How could that be? Sharp at near distance and perfect focus,
unsharp and backfocus 20 meters away...

please have a look and tell me your opinion. that cant be normal :bang:
the original Leitz adapter is ok, I tried it with an other one from my Nokton, which focus perfectly....

It would be very sad, if I have to throw it away...

thanks guys!

marc

 

[riceman]

That does look a bit strange... Decentered.

...

i think so too

is there a possibilty to repair it???


thx!!!