35mm summilux asph focus shift

[Bob]

Well, I just got my 35 summilux back from New Jersey for the second time.
It looks spot on at 1.4, sort of ok at 2.0 and terrible until dof catches up at f/8.
This is the only 1.4 I have for the M and I am sorry to say that I am getting frustrated.
Does anybody know if this is correctable, or shall I propel it at Leica's front door at mach 2?
thanks
-bob

 

[gogopix]

there was somebody here mentioned as having a really good skill in lens adjustments. I would try him/her. If they can't adjust then the focus threads may be off.
A lot of lens variability is blamed on the alignment, but if the threads for individual groups are off, then nothing will work.
was this a new lens?
I would like to know the name as well, since I have some older lenses that have just gone off a little.

BTW, ocassionally there are 'troublesome' lenses the 35mm lux seems one of them. I stuck with the 2.0

if you need a fast lens and can stand a bit narrower FOV, I find the 50mm lux a dream to use. Focus, even in moving situations is pretty easy event for these medicare eyes!

 

[Cindy Flood]

The repair person is Don Goldberg of DAG Camera Repair.
www.dagcamera.com

You can get all of his contact info at the above website or email him at [FONT=trebuchet ms, arial, helvetica][email protected]


[/FONT]

 

[Bob]

Yes it is a new lens and has now been in the shop for most of the almost nine months I have owned it.
I also have the 2.0 and it needs a tweak as well but I have been waiting for the 1.4 to be workable.:angry:
-bob

 

[Terry]

The one thing I have learned is that the 35 lux seems to be the worst offender in the land of focus shift. Tim Ashley had a horrible time with more than one copy.

 

[gtmerideth]

If you search on LUF the subject has been discussed a great deal and my belief is that Leica has stated that the lens works better with film than a digital sensor and can only be adjusted to be perfect in part of it's range.
Call Don and discuss it with him. He is a magician but not for the impossible.
g.

 

[Bob]

I suppose that I can use it close at 1.4 or 2.0 at one meter and far away at the rest.
Maybe a test at 5 meters or so is in order.
-bob

 

[woodyspedden]

Well, I just got my 35 summilux back from New Jersey for the second time.
It looks spot on at 1.4, sort of ok at 2.0 and terrible until dof catches up at f/8.
This is the only 1.4 I have for the M and I am sorry to say that I am getting frustrated.
Does anybody know if this is correctable, or shall I propel it at Leica's front door at mach 2?
thanks
-bob

Bob

This probably won't make you feel any better but you might try to get a silver chrome or titanium version. They apparently have much less of the focus shift problem (due to brass focus helicoids etc) than the black aluminum versions. My copy , silver chrome, had no problems I could discern but of course that is not statistically significant. Other than that I have no offerings.

Best
Woody

 

[harmsr]

Bob,

I had a 35 Lux ASPH that did the same thing which is why I now own the 35 Cron ASPH. Even the 35 Cron ASPH does focus shift at 2.8 & 4.0, but Leica was able to adjust my starting point well enough that it stays in focus at all ranges and apertures.

However, the 35 Lux ASPH I had was off at all apertures to begin with so it went to Germany for a long vacation. When it came back it was spot on at 1.4 then 5.6 & smaller. The back focus was from aperture shift and was very noticeable at 2.0-4.0 when focussing at a close distance. At mid and long distance, the lens was fine due to the additional DOF gained with the distance. My problem is that I often used the 35 in the 1 meter to 3 meter range where the focus shift really showed.

Leica really did try to improve the lens and they did, however all of the 35 Lux ASPH lenses which I have actually used myself did exhibit this problem.

Mine and the loaners were all black - aluminum bodies.

Sorry, for the bad news.

However, you can get a 35 Cron ASPH to work very well. You will basically need to almost front focus at 2.0 and close distance, but then you will stay in focus at all apertures.

Best,

Ray

 

[David K]

I gave up on the 35 lux for the same reasons...

 

[PeterA]

Well - thats bad news ...

 

[mwalker]

Bob, I have one thats spot on out of the box, I wonder why some are and some aren't? Sorry for your frustration.

 

[harmsr]

Mike,

I like your photos in the gallery. At the distances you seem to be shooting, the 35 Lux ASPH is probably fine.

The issue with this lens is in the close focus area out to about 3-4 meters.

I would be interested to see you shoot a test at 1 meter with a series of apertures while not changing the focus point. My bet is that you will notice the focus shift we all see.

If for some reason you don't, I would love to buy your lens.

Best,

Ray

 

[woodyspedden]

Well - thats bad news ...

Pete

Trust me your copy does not have this problem. If I am wrong, just send it back and i will fully reimburse you. I still believe the chrome silvers and titaniums are near faultless compared to the aluminum based black lenses

Woody

 

[Sean_Reid]

The one thing I have learned is that the 35 lux seems to be the worst offender in the land of focus shift. Tim Ashley had a horrible time with more than one copy.

Hi Terry,

I wouldn't say that its the worst offender but, rather, that it has received a lot of Internet forum attention because of this problem. The focus shift is worse, in my experience, with the CV 35/1.4 whereas the CV 35/1.2 and CV 35/1.7 have shown no noticeable focus shifting in my testing. The 35 Lux ASPH that I formally tested on the M8 showed some focus shift but not a dramatic amount. You've seen the test results.

In practice, and I've used the 35 Lux ASPH for assignments where the stakes were high, the pictures I make with this lens don't show a noticeable focus problem at any aperture. The pictures I've made, in normal use, with the two CV 35/1.4 examples I've tested so far, do show focus problems at 2.8 and 4.

Cheers,

Sean

 

[dfarkas]

Last year I shot one of the most critical assignments of my career with the 35 Lux ASPH... my daughter Sophia's birth! The shots came out great. I'd show them, but my wife would probably not be that happy....

That said, I've since found the 35 Cron ASPH to be more to my liking and taste. The cron has less shift, for sure. I would have to second Woody's assesment, though. The chrome luxes do seem to exhibit less shift than the standard black ones.


David

 

[JWW]

Seems like this subject keeps coming up all the time. Just for statistics I had one uncoded chrome one that I sold and my current coded black newer one. Both work great with manageable (negligible) focus shift 2.8-4.0 so to me both identical. Since there is some focus shift due to design even on the optimum 35 asph lenses, it's best to make sure that at 2.0 the focus is toward the front part of focus to give it leeway to move back a bit within the DOF at 2.8-4.0. If adjusted this way, no real problem in real life photos (for me anyways).

Jan

 

[Guy Mancuso]

Frankly I gave up on this lens and bought a Cron.

 

[Digital Dude]

This is all good information but out of curiosity, why is it less of an issue with the silver 35-lux’ lens? Of course, I’m spooked as well and that’s I why I ordered a silver 35-cron so as to stay as far away from this anomaly as possible.
Regards,

 

[Bob]

I am not sure that it is less of an issue, since I have only tested one copy and it was an aluminum model.
One thing to keep in mind is that the effect becomes pretty small at three meters whereas it is very noticeable at one meter. So if all of your shots are at three or more meters away, you are not likely to notice it at all.
In the state of California, which puts notices on everything, one might see "This establishment is aware that f stops of 2.8 through 5.6 may be hazardous to your focus target at distances under three meters"
-bob