Zero Leica lens

[lct]

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Zero Leica lens in my bag. First time it happens to me in half a century. Not that i dislike Leica lenses but for the first time i prefer ZM or VM lenses.
• Sonnar 50/1.5 thanks to the M11 that reduces focus shift, or the effect of it. Now the Sonnar has become my favorite 50 for portraiture, replacing my good old Summilux 50/1.4 v2 or v3 in a smaller package. Only issue is 0.9m MFD but a close focus adapter fixes the issue in LV mode.
• Nokton 35/1.4 SC v2, sort of Summilux 35/1.4 v2 w/o the drawbacks of it. I still use the Summilux but for glow only at f/1.4.
• Nokton 75/1.5. Same comment more or less.
Incredible that i can cram those fast lenses with a 61mp camera and its EVF in a tiny bag BTW. Like in my youth with M4, K25 and f/2 or f/2.8 lenses but i could not dream of carrying a bulky 75/1.4 plus an optical Visoflex in the same bag then. The Leica spirit at its best in Japan 🙂
Do we need really monstrous 90/1.5 and 75/1.25 enses, let alone Godzilla SL lenses?
I'll stop here because I don't want to add my voice to the LUF's chorus of wailers 😄

Edited April 30 by lct

[Rollei35]

1 hour ago, lct said:

Zero Leica lens in my bag. First time it happens to me in half a century. Not that i dislike Leica lenses but for the first time i prefer ZM or VM lenses.
• Sonnar 50/1.5 thanks to the M11 that reduces focus shift, or the effect of it. Now the Sonnar has become my favorite 50 for portraiture, replacing my good old Summilux 50/1.4 v2 or v3 in a smaller package. Only issue is 0.9m MFD but a close focus adapter fixes the issue in LV mode.
• Nokton 35/1.4 SC v2, sort of Summilux 35/1.4 v2 w/o the drawbacks of it. I still use the Summilux but for glow only at f/1.4.
• Nokton 75/1.5. Same comment more or less.
Incredible that i can cram those fast lenses with a 61mp camera and its EVF in a tiny bag BTW. Like in my youth with M4, K25 and f/2 or f/2.8 lenses but i could not dream of carrying a bulky 75/1.4 plus an optical Visoflex in the same bag then. The Leica spirit at its best in Japan 🙂
Do we need really monstrous 90/1.5 and 75/1.25 enses, let alone Godzilla SL lenses?
I'll stop here because I don't want to add my voice to the LUF's chorus of wailers 😄

How does M11 reduces the focus shift? It's a genuine question, not rhetoric.

I noticed same phenomenon, but always wonder why?

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[IkarusJohn]

2 hours ago, lct said:

Sonnar 50/1.5 thanks to the M11 that reduces focus shift, or the effect of it …

What?  Don’t be silly.  Just you wait til @01af sees this … 🫣

[lct]

29 minutes ago, Rollei35 said:

How does M11 reduces the focus shift? It's a genuine question, not rhetoric.

I noticed same phenomenon, but always wonder why?

No idea but i can now shoot my portraits at f/2 with no problem at all.

[UliWer]

vor 5 Stunden schrieb Rollei35:

How does M11 reduces the focus shift?

For sure because it has no bottom plate.  

[01af]

vor 4 Stunden schrieb lct:

... I can now shoot my portraits at f/2 with no problem at all.

That's the way it's supposed to be.

Rangefinder lenses are (or should be) calibrated for perfect focus accuracy at an aperture one stop down from full aperture—that is, f/2 for a 1:1.4 or 1:1.5 lens. So wide open the lens will slightly front-focus and at smaller apertures, slightly back-focus. This distributes the focus error range more or less evenly across the aperture range.

Some users prefer their lenses calibrated for perfect focus at the lens' widest aperture. It's just a matter of mechanical adjustment; any technician can do that in a few minutes. However that wouldn't be a smart move. It would increase the focus shift for any other aperture. And a very slight front-focus at full aperture is not a bad thing, as it will counteract several factors that will introduce some back-focus—including focus-and-reframe (i. e. focusing at one point and then panning the camera so so focused-at point is no longer in the frame's center).

But there's another point in lct's post I find interesting: his contentment with run-of-the-mill lenses on the Leica M11. They are good lenses ... but no extra-ordinarily excellent lenses. So many people are afraid they will need the latest and most expensive super-duper apo-asph glass in order to be able to make good use of the M11's enormous 60 MP resolution. Not so! In fact, a good lens will be good on any camera. If you liked your Planar, Sonnar, Skopar, Ultron, Nokton, whatever on your M cameras in the past then you will love them on the M11. As lct can acknowledge.

[Gregm61]

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I have a 3 lens Voigtlander set I could use happily; 21mm f1.4, 35mm f1.2 III and 75mm f1.5, and all three do extremely well wide open. I’ve just never taken the time to code them so identifying the lens I used 6 months or a year or more later was identifiable. Manually coding as you go is a pain and I’ve always regretted just using them with the coding system off.

[spydrxx]

LCT - Congratulations or condolences, depending on whom you listen to. I've also found offerings by manufacturers other than Leica to do a wonderful job at a seriously reduced price. Yes, I still have a number of Leica screwmount lenses, but more recent additions in M mount have generally been 3rd party ones, and I'm quite pleased with the results.

[Warton]

1 hour ago, 01af said:

That's the way it's supposed to be.

Rangefinder lenses are (or should be) calibrated for perfect focus accuracy at an aperture one stop down from full aperture—that is, f/2 for a 1:1.4 or 1:1.5 lens. So wide open the lens will slightly front-focus and at smaller apertures, slightly back-focus. This distributes the focus error range more or less evenly across the aperture range.

Some users prefer their lenses calibrated for perfect focus at the lens' widest aperture. It's just a matter of mechanical adjustment; any technician can do that in a few minutes. However that wouldn't be a smart move. It would increase the focus shift for any other aperture. And a very slight front-focus at full aperture is not a bad thing, as it will counteract several factors that will introduce some back-focus—including focus-and-reframe (i. e. focusing at one point and then panning the camera so so focused-at point is no longer in the frame's center).

But there's another point in lct's post I find interesting: his contentment with run-of-the-mill lenses on the Leica M11. They are good lenses ... but no extra-ordinarily excellent lenses. So many people are afraid they will need the latest and most expensive super-duper apo-asph glass in order to be able to make good use of the M11's enormous 60 MP resolution. Not so! In fact, a good lens will be good on any camera. If you liked your Planar, Sonnar, Skopar, Ultron, Nokton, whatever on your M cameras in the past then you will love them on the M11. As lct can acknowledge.

You talk like a politician.

I still don’t know why some lenses don’t exhibit focus shift on m11 but do on other cameras 

[UliWer]

vor 5 Minuten schrieb Warton:

I still don’t know why some lenses don’t exhibit focus shift on m11 but do on other cameras 

Well, if you don't like my explanation with the bottom plate I try something else:

As we all know - reading the popular parts of this forum and ignoring the informed ones - the M11 sensor outresolves older lenses. As mostly older lenses show focus shift, this feature is just outresolved by the sensor's high resolution. 

 

[pippy]

10 hours ago, lct said:

....Nokton 35/1.4 SC v2, sort of Summilux 35/1.4 v2 w/o the drawbacks....

...Do we need really monstrous 90/1.5 and 75/1.25 enses, let alone Godzilla SL lenses?...

"Drawbacks"? I was told that all those v2 35mm Summilux aberrations were Plus Points!!!

And yes; 'Godzilla' is a great term for some lenses!......😸.....Recently my brother showed me a snap of a short-to-mid f/l zoom which he had just bought for his DSLR. I replied that it wasn't so much a Lens as a Bazooka. It was bloody ENORMOUS!!!

On the subject of Zero Leica Lenses? The other day I went out with three lenses; 28, 35, and 40. They were a TTA, an LLL and a Voigtlander.

Philip.

Edited April 30 by pippy

[IkarusJohn]

9 hours ago, Warton said:

You talk like a politician.

I still don’t know why some lenses don’t exhibit focus shift on m11 but do on other cameras 

Perhaps the simple explanation is that focus shift is a feature of the lens, as 01af explained above.  Focus shift can easily be eliminated, if you use an EVF.  The sensor itself has no effect on focus shift - resolution, yes; focus shift, no.  While a higher resolving sensor or film will increase the detail captured, there is no planet upon which it will bring at out of focus image (at the lens) into focus.  More resolution, yes, but not focus.

[jaapv]

Politicians lie, 01af not...

The camera type does not matter,  it is the same for M8 to M11 and anything in between.

Focus is determined by the distance between sensor and lens. For a lens with focus shift the optimal adjustment is one stop down (*), as O1af explains. However, both lens adjustment and sensor position are within a certain tolerance range. If these tolerances add up, the lens will exhibit  focus shift, if they cancel out you will see minimum focus shift, maybe none at all. The type of M camera is irrelevant, the individual camera counts.
One can ask Leica to do tolerance matching between the camera and the lens.

(*) As DOF will mitigate focus shift unsharpness.

 

12 hours ago, Warton said:

You talk like a politician.

I still don’t know why some lenses don’t exhibit focus shift on m11 but do on other cameras 

 

[jaapv]

14 hours ago, 01af said:

 So many people are afraid they will need the latest and most expensive super-duper apo-asph glass in order to be able to make good use of the M11's enormous 60 MP resolution. Not so! In fact, a good lens will be good on any camera. If you liked your Planar, Sonnar, Skopar, Ultron, Nokton, whatever on your M cameras in the past then you will love them on the M11. As lct can acknowledge.

An excellent point which needs to be made time and time again. 

https://www.lensrentals.com/blog/2019/10/more-ultra-high-resolution-mtf-experiments/

Scroll down for the relevant conclusion. Lens-sensor resolution, or quality if one insists, is not a weakest link situation. Any lens will do better on a better sensor, any sensor will do better with a better lens. 

 

[IkarusJohn]

3 hours ago, jaapv said:

Politicians lie, 01af not...

The camera type does not matter,  it is the same for M8 to M11 and anything in between.

Focus is determined by the distance between sensor and lens. For a lens with focus shift the optimal adjustment is one stop down (*), as O1af explains. However, both lens adjustment and sensor position are within a certain tolerance range. If these tolerances add up, the lens will exhibit  focus shift, if they cancel out you will see minimum focus shift, maybe none at all. The type of M camera is irrelevant, the individual camera counts.
One can ask Leica to do tolerance matching between the camera and the lens.

(*) As DOF will mitigate focus shift unsharpness.

 

 

Interesting - you’re saying there is variation between cameras in depth of focus?

[SrMi]

44 minutes ago, IkarusJohn said:

Interesting - you’re saying there is variation between cameras in depth of focus?

As I understand it, it is not the depth of focus but the point of focus.

 

[IkarusJohn]

58 minutes ago, SrMi said:

As I understand it, it is not the depth of focus but the point of focus.

 

Not a phrase I’m familiar with, Srdjan.

[SrMi]

1 hour ago, IkarusJohn said:

Not a phrase I’m familiar with, Srdjan.

I meant the focal plane which moves slightly because of mechanical tolerances when using the rangefinder.

Depth of field should not be different between various FF M models.

 

[roelandinho]

8 hours ago, jaapv said:

Focus is determined by the distance between sensor and lens. For a lens with focus shift the optimal adjustment is one stop down (*), as O1af explains. However, both lens adjustment and sensor position are within a certain tolerance range. If these tolerances add up, the lens will exhibit  focus shift, if they cancel out you will see minimum focus shift, maybe none at all. The type of M camera is irrelevant, the individual camera counts.

While I agree with you and O1af, I just want to mention (because I think some people may get confused by this), the focus shift is a property of the lens, and refers to the plane of best focus shifting backwards as the aperture is closed. If you put the same lens on different cameras, the focus shift doesn't change. What does vary is the amount of error you can experience by this (if you blindly trust the rangefinder). 

• Worst case: your camera system (sensor + lens combination) already back-focuses at full aperture because of calibration issues. This back-focus will only get worse as you stop down because the plane of focus moves backwards. (Obviously depth-of-field will increase also which makes this less bad, but still the background will always be sharper than your subject...)
• Better, but not ideal for most people: your camera system focuses perfectly at full aperture. This is ideal if you only use the lens at max aperture, but the focus shift will cause significant back-focus at all other apertures. 
• Best for most people: perfect focus at approx. one stop down from full aperture. This will cause slight front-focus at full aperture (much preferable to back-focus if you photograph a subject against a background), and also a bit of back-focus at smaller apertures. It's a compromise that minimizes the "largest possible focus error" you can experience when trusting the rangefinder. I personally still overrule the rangefinder at smaller apertures in this case to correct the back-focus. 
• Last option: perfect focus at a small aperture. This leads to significant front-focus at large apertures and is probably not a useful option, unless you only shoot landscapes stopped down. 

In all these cases the focus shift of the lens is the same, but the problematic effects you experience when blindly following the rangefinder can be greater or smaller depending on the calibration and your personal usage pattern. 

Edited May 1 by roelandinho

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[IkarusJohn]

3 hours ago, SrMi said:

I meant the focal plane which moves slightly because of mechanical tolerances when using the rangefinder.

Depth of field should not be different between various FF M models.

 

I’m still not with you.

The focal plane is at the sensor - it used to be marked on the top deck.  How does that move when using the rangefinder?

The depth of focus is the depth of the plane of best focus at the focal plane - not such a problem with the thick emulsion on film, more of a problem with a digital sensor.  It’s quite different from depth of field and focus shift.  Focus shift is when the image projected by the lens is at the focal plane at, say, f/2 and then moves away as the lens is stopped down, making the image at the focal plane out of focus, until the the depth of field brings the image back into acceptable focus - at f/5.6 or smaller.

Famously a problem with the 35 Summilux ASPH (first version) and the f/1 Noctilux.

Now, I know that some wil quibble with that explanation, but my point is, I’m not sure I follow how the rangefinder has any impact on the lens, or the depth of focus, or the focal plane, for that matter.  The focal plane stays in the same place.  It’s the plane of best focus that shifts as the lens is stopped down.  That’s the problem …