Summilux-SL 50 MM F/1,4 ASPH

[zlatkob]

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I think you have to make a distinction between digital corrections that are meant to improve an already optically corrected (as far as possible) lens that is not camera body specific and which is designed to be primarily used via an optical viewing system (for example, a modern Nikon AF-S lens that, whilst typically used on a Nikon DSLR, will also be perfectly fine on a film body like the F5) and a lens that is designed to be solely used in conjunction with an EVF based digital body that implements the necessary digital corrections. The latter lens is likely to be deliberately less optimal from an optical perspective (i.e. as a standalone optical unit) because, by not correcting (optically) for those distortions or aberrations which are easily corrected digitally, the lens designer can avoid the introduction of other more serious (less easily corrected digitally) side effects. The overall balance of optical and digital correction results in a "better" overall image and removing those digital corrections is therefore akin to removing the aspherical lens from a conventional optically corrected lens.

 

That sounds like a plausible theory, but that distinction does not hold in the real world.  For example, the Sony FE 28mm f/2 lens is designed solely to be used in conjunction with an EVF based digital body (Sony A7 series) which implements the "necessary" corrections.  That lens will never be used via an optical viewing system.  Without corrections, that lens has rather strong barrel distortion.  With corrections, it is highly rectilinear and vignetting is removed — good for many purposes.  But if you photograph people with that lens, you may sometimes prefer its uncorrected image.  And for some high ISO photos (with or without people), you may prefer to leave in the vignetting, avoiding some of the noise that becomes apparent from digital vignetting correction.  Fortunately, the digital corrections are not baked-in to the Raw file, so the photographer can make the choice, expressing each image as they wish.  

 

That is the nature of the distortion and its correction. The distortion is created by a lens with a magnification factor that varies with the distance from the center of the image. So is, of course, the correction.

 

You'd just as soon state that everything seems darker when you wear sunglasses.

Yes, thank you, it is the nature of correction.  I had to explain it because I've been accused of saying something absurd.  But more importantly, correction is not always wanted because it can make people look worse.  Almost no one seems to get this last point.  Thankfully Adam knows what I'm talking about.

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[wattsy]

That sounds like a plausible theory, but that distinction does not hold in the real world. 

 

 

Of course it holds. There is an obvious difference between an optically corrected lens with optional digital improvements (such as those offered in Lightroom) and a lens that is designed to be corrected digitally. If you choose to use the latter lens uncorrected (as with your example of the Sony 28mm lens) you are simply using it in a way that it was not designed for. Not dissimilar to, for example, removing one of the glass components from a traditional optically corrected lens. If that's what you want to do, that's fine, but you can't complain that the lens isn't very good.

[LocalHero1953]

My guess is that we're talking about this now because distortion (and vignetting) are probably the easiest lens faults to correct digitally. It would makes sense, therefore, to concentrate optical corrections on coma, CA, sharpness etc at the expense of distortion and vignetting. The final lens will inevitably look worse (distorted) without digital correction than a lens designed to compromise across the range.

 

Does this make it a bad lens? Not to me, and I am sure the Leica lens designers intentionally designed it as it is, without cutting corners.

 

I can understand why others disagree. Trying not to adopt the snide tone often heard on this forum, I suggest with all sincerity that this lens is not for them: this lens has explicitly been designed not for those who want a purely optical product, and if you use it as such it will be much worse than the competition (including the Apo 50 M).

[zlatkob]

Of course it holds. There is an obvious difference between an optically corrected lens with optional digital improvements (such as those offered in Lightroom) and a lens that is designed to be corrected digitally. If you choose to use the latter lens uncorrected (as with your example of the Sony 28mm lens) you are simply using it in a way that it was not designed for. Not dissimilar to, for example, removing one of the glass components from a traditional optically corrected lens. If that's what you want to do, that's fine, but you can't complain that the lens isn't very good.

 

The point there is that Sony lets you use the lens either way, not just one way.  The digital corrections are applied by default, but can be turned off in the Raw file.  In other words, the corrections are not "baked-in".  Giving the photographer this option recognizes that the corrections will not always be wanted by the photographer because, for some images, the corrected version will look worse.  So when you choose to use the lens uncorrected, you are using it in a way that the designer specifically allowed.  In other words, the designer understood the issue and put the photographer in charge of the final image.

[Peter Branch]

All companies have a philosophy, often they seek to make it unique.  This in modern parlance is sometimes equated with their USP (Unique Selling Point).

 

Leica is no different, in fact it has been more consistent than most in seeking always to provide users with the tools to maximise Image Quality, (IQ), in the widest range of circumstances.

Given this, why would Leica be concerned to provide a specific capability to reduce IQ?

 

Sony, et. al. can do as they please.

If users wish to manipulate the image, for whatever reason, then there are many ways to do this.

 

All optical systems, for that is what we are dealing with, involve compromises.

Leica will have designed the SL System, optics, hardware and software, in line with their philosophy.

The resulting IQ is, on all the evidence available, in the premier league.

 

There is absolutely no reason to doubt at this stage that all new SL lenses, when used on the Leica SL as Leica intended, will offer superb IQ.    

[thighslapper]

From what I have read barrel distortion ( which this lens apparently has) is the easiest aberration to correct as it follows a predictable mathematical model.

 

I also suspect it is a product of the need to keep the moving AF lens elements as small as possible .... as a 'stop' in the optical path is a generator of the aberration itself.

 

I suspect Leica worked backwards in designing this lens ...... deciding what was the acceptable fully correctable level of rectilinear/radial distortion in firmware that did not impact on image quality and the maximum size of moving IF elements that gave acceptably fast and accurate AF ....... and then designed the rest of the lens to eliminate the other remaining and more problematic distortions. 

 

I think AF imposes more optical problems than just moving a few lenses about with a motor ..... 

[jrp]

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One of the Leica Reps at PhotoKina did suggest that the new Summicrons would be at a new performance level.

 

I can't tell about the Summilux from the pics on the blog because they appear, for idiosyncratic reasons, to have been manipulated to remove the digial correction indicators that are what the normal user would see (eg, from an out of camera JPEG).

 

The 16-35mm was described as being merely of the current Vario performance level (which is good enough for me).

 

This more or less accords with what Peter Karbe was saying in another interview.

 

To me we are now beyond the point where basic performance will determine whether a lens is worth buying or not.  No picture that I have taken with the current SL zooms has been limited by lens performance.  (That was not the case with my previous DSLR system, and with some of the fast M lenses, which make field curvature and edge performance compromises.)

 

Instead, I look at the rendering (contrast, bokeh, saturation, resistance to flare / fringing, etc) and ergonomics (notably bulk/weight).

 

On that basis the 50mm looks v good to me, but is too bulky and, for me, makes little sense, as I wouldn't use the 50mm for portraits, much less f1.4, which is what the AF would bring over the static subject M lenses.

[zlatkob]

All companies have a philosophy, often they seek to make it unique.  This in modern parlance is sometimes equated with their USP (Unique Selling Point).

 

Leica is no different, in fact it has been more consistent than most in seeking always to provide users with the tools to maximise Image Quality, (IQ), in the widest range of circumstances.

Given this, why would Leica be concerned to provide a specific capability to reduce IQ?

 

Sony, et. al. can do as they please.

If users wish to manipulate the image, for whatever reason, then there are many ways to do this.

 

All optical systems, for that is what we are dealing with, involve compromises.

Leica will have designed the SL System, optics, hardware and software, in line with their philosophy.

The resulting IQ is, on all the evidence available, in the premier league.

 

There is absolutely no reason to doubt at this stage that all new SL lenses, when used on the Leica SL as Leica intended, will offer superb IQ.    

 

I think I've answered that question a bunch of times already.  The problem with the question is that things are not that simple in the digital era.  If you're talking about "the widest range of circumstances", then you have to consider that digital corrections sometimes worsen a picture.  And if you can't turn the corrections off, then you've eliminated a tool rather than provided a tool.  

[pop]

I think I've answered that question a bunch of times already.  The problem with the question is that things are not that simple in the digital era.  If you're talking about "the widest range of circumstances", then you have to consider that digital corrections sometimes worsen a picture.  And if you can't turn the corrections off, then you've eliminated a tool rather than provided a tool.  

In this case, you never should buy a lens which optically eliminates this kind of distortion, as you most certainly can not turn off the optical correction, thus depriving yourself of a valuable tool only made possible by digital correction of the distortion.

[zlatkob]

In this case, you never should buy a lens which optically eliminates this kind of distortion, as you most certainly can not turn off the optical correction, thus depriving yourself of a valuable tool only made possible by digital correction of the distortion.

 

No worries about that.  It is extremely unlikely I will ever buy a lens that is optically so perfect that is has 0% distortion and 0% vignetting, such that I can't turn off the optical correction.  Somehow my lens journey always involves some optical imperfections.  

[jmahto]

Trying to get my head around the objections. Is the only issue with this lens not having access to the uncorrected image? Is uncorrected image excellent (sans distortion being the factor which is preferable in some cases, as expressed by some)?

[jaapv]

I think I've answered that question a bunch of times already.  The problem with the question is that things are not that simple in the digital era.  If you're talking about "the widest range of circumstances", then you have to consider that digital corrections sometimes worsen a picture.  And if you can't turn the corrections off, then you've eliminated a tool rather than provided a tool.  

But it is likely that you can obtain an uncorrected image using RawTherapee, so what is the problem?

[zlatkob]

But it is likely that you can obtain an uncorrected image using RawTherapee, so what is the problem?

 

I'm not familiar with that app, but yes, that may be the practical solution if it works.  My point is more about manufacturers making a sound design choice in the first place, so as not to require workarounds.

[FlashGordonPhotography]

Lens Designer: ​"Hey Gordon. I've made you this great new lens. It's sharp with great micro contrast. The blur is really nice while maintaining fabulous centre resolution wide open and great overall performance stopped down. A really nice all round lens"

 

Gordon: ​"Thanks. Unfortunately the last 5% of the corners never get as sharp as the centre and there's a mid zone dip. This week I'm a landscape photographer. Is there anything you can do about that"

 

Lens Designer: ​"OK, I'll replace a couple of the elements with aspherical glass. That'll make it really sharp to the corners for you."

 

Gordon ​"Hmmm. Better. But I'm still seeing some CA. And are those onion rings? Can't we do something about those? I can't shoot portraits with this."

 

​Lens Designer: ​Well I can add a couple of apochromatic elements. It'll make the lens more complicated but leave it with me...."

 

Gordon​: By the way any chance you could add AF and IS?"

 

​Lens Designer: It'll mean many more elements and potential optical issues but I'll do what I can."

 

Gordon: ​"New lens is great but I just took a photo of a brick wall for a client and I notice there's some distortion. Next week I'm going to be an architecture photographer but I only want to own one lens. What can you do for me?"

 

Lens Designer:​ Well, the lens has become very complicated optically because of all the other things we've added to the base design. But there's this revolutionary new thing called *software*. I'll investigate...."

 

OK. Using the revolutionary *software*, I've managed to remove the distortion that was created by adding the APO elements. I've also removed the CA that was exaggerated because of the 14 ASPH elements. It's good to the corners wide open and has buttery bokeh"

 

Gordon: "Whoa Nelly!!! Look at the size of that thing! And the cost!. You've gotta be kidding me? And I don't like this new fangled mumbo jumbo cause one shot in a hundred I might notice something I don't like. I just don't get why you've done all this stuff. Can't you just make me a small, cheap simple lens that's good as an all rounder? 

 

​Lens Designer: sigh!

 

***********************

 

So glad I just buy 'em.

 

Gordon

[LD_50]

Lens Designer: ​"Hey Gordon. I've made you this great new lens. It's sharp with great micro contrast. The blur is really nice while maintaining fabulous centre resolution wide open and great overall performance stopped down. A really nice all round lens"

 

Gordon: ​"Thanks. Unfortunately the last 5% of the corners never get as sharp as the centre and there's a mid zone dip. This week I'm a landscape photographer. Is there anything you can do about that"

 

Lens Designer: ​"OK, I'll replace a couple of the elements with aspherical glass. That'll make it really sharp to the corners for you."

 

Gordon ​"Hmmm. Better. But I'm still seeing some CA. And are those onion rings? Can't we do something about those? I can't shoot portraits with this."

 

​Lens Designer: ​Well I can add a couple of apochromatic elements. It'll make the lens more complicated but leave it with me...."

 

Gordon​: By the way any chance you could add AF and IS?"

 

​Lens Designer: It'll mean many more elements and potential optical issues but I'll do what I can."

 

Gordon: ​"New lens is great but I just took a photo of a brick wall for a client and I notice there's some distortion. Next week I'm going to be an architecture photographer but I only want to own one lens. What can you do for me?"

 

Lens Designer:​ Well, the lens has become very complicated optically because of all the other things we've added to the base design. But there's this revolutionary new thing called *software*. I'll investigate...."

 

OK. Using the revolutionary *software*, I've managed to remove the distortion that was created by adding the APO elements. I've also removed the CA that was exaggerated because of the 14 ASPH elements. It's good to the corners wide open and has buttery bokeh"

 

Gordon: "Whoa Nelly!!! Look at the size of that thing! And the cost!. You've gotta be kidding me? And I don't like this new fangled mumbo jumbo cause one shot in a hundred I might notice something I don't like. I just don't get why you've done all this stuff. Can't you just make me a small, cheap simple lens that's good as an all rounder? 

 

​Lens Designer: sigh!

 

***********************

 

So glad I just buy 'em.

 

Gordon

The Lens Designer for the 50SL could talk to the designer of the Otus 55. The only missing element mentioned here is the AF. Unmentioned is the weather sealing. Both are heavy and large and expensive.

 

One is called by its maker (Leica) a "reference lens," is said to "deliver maximum optical performance", and "establishes new benchmark standards in terms of sharpness." The other is called by its maker (Zeiss) "the best standard lens in the world."

 

One likely relies on software correction of the image, the other doesn't. It will be interesting to see how the final images compare from each. If post-digital correction the 50SL images are still better than what the Otus produces, kudos to Leica. This would be all the more impressive with the internal focusing elements likely making the design constraints more challenging.

[jaapv]

I'm not familiar with that app, but yes, that may be the practical solution if it works.  My point is more about manufacturers making a sound design choice in the first place, so as not to require workarounds.

Well, using a shareware raw developer is not too much of a workaround - if it works

 

I disagree about the sound design choices bit - a lens designer is free to use any tool that becomes available in the course of technological progress if it improves the result in my book.

[zlatkob]

Well, using a shareware raw developer is not too much of a workaround - if it works

 

I disagree about the sound design choices bit - a lens designer is free to use any tool that becomes available in the course of technological progress if it improves the result in my book.

 

As I wrote above, lens designers should use every tool at their disposal.  On that much we agree.  My point is that the photographer should still have the final decision on how the image should be expressed, either with or without digital corrections.   Because digital corrections do not always improve the result.

[jaapv]

But the designer has the right to present the lens as he designs it, including all the corrections he deems necessary.

I fail to see the difference to demanding that a designer  offers an optically corrected rectilinear lens with the element that reduces distortion  user-removable because having distortion might be an advantage in a small percentage of cases. Or with a floating element lockable because locking it might improve OOF rendering  sometimes.

 

If a lens as-is fails to meet your artistic demands you are using the wrong lens.

 

With hybrid-corrected lenses you are indeed able to remove part of the correction by choosing the right raw developer. It is a side-effect one might use under one's own responsibility. To put the onus on the designer to accommodate the worsening of his design is incorrect.

 

We see it so often on the Internet nowadays. A manufacturer offers a product. Instead of buying it or not buying it according to one's wishes, people demand that the producer changes the product to their own personal specification.

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Hallo,

Look here: Leica L-Mount

[zlatkob]

But the designer has the right to present the lens as he designs it, including all the corrections he deems necessary.

I fail to see the difference to demanding that a designer  offers an optically corrected rectilinear lens with the element that reduces distortion  user-removable because having distortion might be an advatage in a small percentage of cases. Or with a floating element lockable because locking it might improve OOF rendering in some cases.

 

If a lens as-is fails to meet your artistic demands you are using the wrong lens.

 

With hybrid-corrected lenses you are indeed able to remove part of the correction by choosing the right raw developer. It is a side-effect one might use under one's own responsibility. To put the onus on the designer to accommodate the worsening of his design is incorrect.

 

We see it so often on the Internet nowadays. A manufacturer offers a product. Instead of buying it or not buying it according to one's wishes, people demand that the producer changes the product to their own personal specification.

 

The lens designer has the "right" to do anything.  But it's not a question of rights.  It's a question of good design.  Good design is photographer-centered, giving control to the photographer over key elements of photographic expression.  I've explained the occasional but real problem of digital corrections over and over again.  It's the classic problem of a perfectly rectilinear lens distorting the shapes of objects (people) toward the corners.  Why deny this?  It's just a fact.

 

The analogy to a user-removable element fails totally because digital corrections are different.  It's no more relevant than someone else's analogy to ABS brakes in an auto.  I'm not going to struggle to address misplaced analogies when we can accurately talk about the *exact* thing we are talking about:  digital corrections.

 

I'm not inventing some bizarre new onus on lens designers.  Nor is this a personal specification.  User-selectable digital corrections have been the standard thus far, at least among professional cameras.  The lack of user control over digital corrections is the surprising new exception, not the standard.  I suspect it has been the standard because (most) designers recognize that the user should retain this control when there is no one-size-fits-all perfect digital correction.

[almoore]

User-selectable digital corrections have been the standard thus far, at least among professional cameras.  The lack of user control over digital corrections is the surprising new exception, not the standard.  I suspect it has been the standard because (most) designers recognize that the user should retain this control when there is no one-size-fits-all perfect digital correction.

It has been the standard because - until very recently - optical viewfinders have been the norm.