28mm Summilux peculiar problem

[darlesch]

Advertisement (gone after registration)

I love my 28mm Summilux. That said, I have this peculiar problem I don't notice with any of my other lenses.

In landscape/horizontal orientation, the lens is spot on. My digital M has also been calibrated at NJ.

However, when I shoot in vertical orientation, the images are slightly back focused, no matter how I shoot - whether I rack focus from infinity to the target vertically or focus horizontally and re-orient to vertical orientation - all slight back focus.

Here is the weird part: when I re-orient from vertical orientation back to horizontal orientation... the back focus goes away and focus is spot on (experiment done on a SpyderLensCal target). I am deliberately focusing on the target the same way I would in landscape orientation. None of my other lenses show this behavior. 

I noticed this problem when I shot portraits in vertical orientation and the eyes were slightly out of focus.

Any thoughts?

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[LeicaR10]

Darlesch,  Quite interesting.  I once owned the 28 Summilux and never had that issue using it vertically.  I know others might chime in with ideas, but I suggest your 28 Summilux lens might need to go for a 100K mile check up.  If the lens is out of warranty, I would call Don Goldberg at DAG and he might give you some advice.  Worst case, you send him the lens and M camera for a check up.  This is what I do with all my M gear out of warranty for years and he is most excellent with calibrations and repairs.  Plus a lot less expensive than NJ and much faster too.  He will also give you a good estimate too.  Just be sure to tell him when you need the lens/camera back.  You will find many M photographers who will vouch for Don's work on this forum.  r/ Mark

Edited November 29, 2024 by LeicaR10

[darlesch]

Just now, LeicaR10 said:

Darlesch,  Quite interesting.  I once owned the 28 Summilux and never had that issue using it vertically.  I know others might chime in with ideas, but I suggest your 28 Summilux lens might need to go for a 100K check up.  If the lens is out of warranty, I would call Don Goldberg at DAG and he might give you some advice.  Worst case, you send him the lens and M camera for a check up.  This is what I do with all my M gear out of warranty for years and he is most excellent with calibrations and repairs.  Plus a lot less expensive than NJ and much faster too.  He will also give you a good estimate too.  Just be sure to tell him when you need the lens/camera back.  You will find many M photographers who will vouch for Don's work on this forum.  r/ Mark

Thanks for the reply. Good to know that your vertical results are not the same. I have sent an e-mail out to Leica and various technicians including Don for their opinion on the cause of this problem. I'm afraid it will have to go in for service. 

[LeicaR10]

Darlesch,  Don is quite a busy man, it might take him a while to email you back.  It is way easier to simply call him and describe the problem and see what he says.  r/ Mark

[hdmesa]

On 11/28/2024 at 9:00 PM, LeicaR10 said:

...If the lens is out of warranty, I would call Don Goldberg at DAG and he might give you some advice...

I thought the Leica lenses with floating element groups like the 28 Lux had to be calibrated on special equipment at Leica Germany.

[darlesch]

4 minutes ago, hdmesa said:

I thought the Leica lenses with floating element groups like the 28 Lux had to be calibrated on special equipment at Leica Germany.

It seems true. YYE stated the same and said he was unable to look at it. Don being Don and being trained at Wetzlar, maybe that’s a different story. Don said to send it in.

I’m actually going to keep the lens since it works perfectly in one orientation. Bizarre. The back focus is mild in vertical orientation so it hasn’t driven me insane… yet.

[hdmesa]

Advertisement (gone after registration)

Just now, darlesch said:

It seems true. YYE stated the same and said he was unable to look at it. Don being Don and being trained at Wetzlar, maybe that’s a different story. Don said to send it in.

I’m actually going to keep the lens since it works perfectly in one orientation. Bizarre. The back focus is mild in vertical orientation so it hasn’t driven me insane… yet.

Have you tried focusing it in the opposite direction to see if that eliminates the back focus in vertical orientation? What about flipping the camera vertical but in the opposite direction than you normally do? Another idea, when shooting vertically, see if you're resting more of the camera weight on the focus tab than you do in the horizontal orientation. I've seen back/front focus if too much pressure is applied to the focus ring on some lenses.

[darlesch]

1 minute ago, hdmesa said:

Have you tried focusing it in the opposite direction to see if that eliminates the back focus in vertical orientation? What about flipping the camera vertical but in the opposite direction than you normally do? Another idea, when shooting vertically, see if you're resting more of the camera weight on the focus tab than you do in the horizontal orientation. I've seen back/front focus if too much pressure is applied to the focus ring on some lenses.

All great thoughts and unfortunately I've already tried these ideas:

- While vertical, opposite direction focusing: yes at closer distances (<3m) this rectifies the problem, but at mid range (3 meters), it is no different than previous

- Flipping camera upside down (i.e. elbows close to chest): no change from previous

- Resting weight too much on focus tab: have tried both single finger focus tab movement as well as 'pinching' i.e. using thumb and index to turn the ring without using the tab

All great ideas and funnily enough, these workarounds HAVE worked on one of my other lenses, but alas none has worked so far with this particular lens.

Seems like a very mechanical problem but in the end I'm still content and wouldn't want to send it in for who knows how long.

If someone could chime in and discovered they too have a mild back focus issue in the vertical orientation that would make me feel even better.
 

[hdmesa]

1 minute ago, darlesch said:

All great thoughts and unfortunately I've already tried these ideas:

- While vertical, opposite direction focusing: yes at closer distances (<3m) this rectifies the problem, but at mid range (3 meters), it is no different than previous

- Flipping camera upside down (i.e. elbows close to chest): no change from previous

- Resting weight too much on focus tab: have tried both single finger focus tab movement as well as 'pinching' i.e. using thumb and index to turn the ring without using the tab

All great ideas and funnily enough, these workarounds HAVE worked on one of my other lenses, but alas none has worked so far with this particular lens.

Seems like a very mechanical problem but in the end I'm still content and wouldn't want to send it in for who knows how long.

If someone could chime in and discovered they too have a mild back focus issue in the vertical orientation that would make me feel even better.
 

Could be the same principle at work internally – if the floating element group were slightly loose for example, but it doesn't have room to droop and apply additional leverage unless the lens is in the vertical orientation. Might be worth checking the lens wide open at infinity in the vertical orientation and see if one side of the frame is slightly softer than the other compared to the same shot in the horizontal orientation.

[darlesch]

8 minutes ago, hdmesa said:

Could be the same principle at work internally – if the floating element group were slightly loose for example, but it doesn't have room to droop and apply additional leverage unless the lens is in the vertical orientation. Might be worth checking the lens wide open at infinity in the vertical orientation and see if one side of the frame is slightly softer than the other compared to the same shot in the horizontal orientation.

Yes, that would be my greatest fear i.e. decentering... but all is good thankfully on all corners / edges.

I think it has to do with the weight of the lens and how much force is required to rack focus vertically. For whatever reason, gravity in vertical orientation isn't doing this copy any favours. 

Edited November 30, 2024 by darlesch

[hdmesa]

19 minutes ago, darlesch said:

Yes, that would be my greatest fear i.e. decentering... but all is good thankfully on all corners / edges.

I think it has to do with the weight of the lens and how much force is required to rack focus vertically. For whatever reason, gravity in vertical orientation isn't doing this copy any favours. 

Makes sense. Maybe just needs adjustment or a lighter grease. Don will get you squared away.

[darlesch]

12 hours ago, hdmesa said:

Makes sense. Maybe just needs adjustment or a lighter grease. Don will get you squared away.

After some testing and using your help, I am now able to achieve accurate focus with no compromises with some new, still peculiar, observations:

- The lens DOES indeed back focus in landscape (unbeknownst to me) if I press too hard on the focus tab after racking from infinity to target. The back focus in landscape disappears once I lift the finger before releasing the shutter.

- In portrait, I revisited racking focus from 0.7m to target. Results are now consistent at all distances provided, now knowing the above, that I do not keep pressure on the focus tab with my finger when I release the shutter.

Leica is wonderful, great, mysterious, and ultimately mechanical, for better or worse. So long as I have these workarounds, which aren't too much of a nuisance, I now do not have to part ways with it for service.

Thanks hdmesa for your experience, that's exactly why I posted here.

[Sebastian S]

something in the lens is obviously faulty. "fixing" it with workarounds could led to more and more serious damage or even wear of mechanical or optical parts that can't be undone without part changes. wouldn't recommend that solution

[hdmesa]

11 hours ago, darlesch said:

After some testing and using your help, I am now able to achieve accurate focus with no compromises with some new, still peculiar, observations:

- The lens DOES indeed back focus in landscape (unbeknownst to me) if I press too hard on the focus tab after racking from infinity to target. The back focus in landscape disappears once I lift the finger before releasing the shutter.

- In portrait, I revisited racking focus from 0.7m to target. Results are now consistent at all distances provided, now knowing the above, that I do not keep pressure on the focus tab with my finger when I release the shutter.

Leica is wonderful, great, mysterious, and ultimately mechanical, for better or worse. So long as I have these workarounds, which aren't too much of a nuisance, I now do not have to part ways with it for service.

Thanks hdmesa for your experience, that's exactly why I posted here.

Glad you have a workaround, but I would still send it to Don to look at it. Probably just needs something tightened up or a worn part replaced.

 

[darlesch]

Thank you all for your responses.

I took the lens out last night for my daughters' birthdays. Incredible lens. All the shots were great with the workarounds (not too big of a deal IMO). What is a big deal though is the focus ring is severely stiff since the lubricant is probably old.

The copy I have is the limited silver (I bought it used, or maybe it was stored I'm not sure), which is why I was reluctant to send it off. In the end, it would've happened eventually given that the issues are quite problematic and it's better to send it now and get it over with. I will be requesting that NJ sends it to Wetzlar or if NJ feels they can fix it, I would be very thankful. 

[hdmesa]

On 12/1/2024 at 1:44 PM, darlesch said:

Thank you all for your responses.

I took the lens out last night for my daughters' birthdays. Incredible lens. All the shots were great with the workarounds (not too big of a deal IMO). What is a big deal though is the focus ring is severely stiff since the lubricant is probably old.

The copy I have is the limited silver (I bought it used, or maybe it was stored I'm not sure), which is why I was reluctant to send it off. In the end, it would've happened eventually given that the issues are quite problematic and it's better to send it now and get it over with. I will be requesting that NJ sends it to Wetzlar or if NJ feels they can fix it, I would be very thankful. 

Don at DAG uses new old stock Leitz 1960s grease that works better for re-lubricating these lenses than the newer grease Leica uses. 

 

[darlesch]

13 minutes ago, hdmesa said:

Don at DAG uses new old stock Leitz 1960s grease that works better for re-lubricating these lenses than the newer grease Leica uses. 

 

I hear you. I love DAG and he knows that. He fixed my M2 up quite well.

For this lens though, it seems so many issues are present I think only Wetzlar can diagnose and repair properly. 

[hdmesa]

30 minutes ago, darlesch said:

I hear you. I love DAG and he knows that. He fixed my M2 up quite well.

For this lens though, it seems so many issues are present I think only Wetzlar can diagnose and repair properly. 

If it's going to Wetzlar, just get a full CLA in addition to noting the mechanical issue you're experiencing. Being that it's a somewhat rare lens, I think it would be worth it!

[Advertisement]

Hallo,

Look here: Leica M