Leica R - what am I missing?

[Film-Niko]

I don't doubt that the latest Leica lenses are excellent, but I suspect for many situations the lens isn't the weakest element in the photographic chain.

The weakest element is certainly in most cases the photographer. But nevertheless it makes sense to eliminate as many weak elements in the photographic chain as possible.

Under idea conditions such as camera on a tripod, mirror locked up, high resolution film and a static subject I'm sure there is a difference to be seen between a Leica lens and Canon, Nikon, Pentax etc.

You should not concentrate on what brand is used. But whether you have a lens built to modern science and standards, or an old, outdated one.
The current Pentax 1.4/50 DFA and 1.4/85 DFA for example are much better than the former Leica and Zeiss 1.4/50 and 1.4/80 / 1.4/85 lenses which were designed in the seventies.
Lens design and construction (huge advances in production of aspherical lenses, new improved glass types, tighter tolerances in manufacturing.....) has improved so much in the last decades.

And these differences are huge, and are visible not only under ideal circumstances as you guess, but generally and in lots of different situations.

 

[Henning Serger]

Under idea conditions such as camera on a tripod, mirror locked up, high resolution film and a static subject I'm sure there is a difference to be seen between a Leica lens and Canon, Nikon, Pentax etc.

I agree with Film-Niko above: In the last years the brand of the lens has become much less important, as today even lens manufacturers like Sigma and Tamron have certain lenses in their programmes, of which Leica and Zeiss would have been proud of having in their programmes 20 years ago.

So the decisive factor is indeed having a modern lens design which matches perfectly today's advanced highest standards versus having an old lens design from the 60ies, 70ies or 80ies.
And from my tests - and those of very experienced photographer friends and professional test institutions - I have to say the difference of most of these modern high-performance lenses compared to the older designs is really very significant and very clearly visible.
And very clearly visible not only under ideal conditions with a camera on a tripod, MLU, high resolution film etc., but also very clearly visible in normal, standard all-day handheld photography with all kind of films.

I can often see that difference already when looking at my transparencies on the light table even without (!!) using a loupe. Especially when I compare the results of my latest Zeiss lenses compared to my Nikkors which were designed in the 70ies.
Two different worlds in optical and mechanical performance. And the reason why my older Nikkors are rareley used anymore, being de-facto 'retired'.

However, under less than perfect conditions, such as in a jazz club using Delta 3200 handheld at 1/30 s I doubt there would be any discernible difference on the negatives between a Leica and others.

In such situations I am always using my best modern lenses, because I really benefit from them: In my local Jazz club there is a certain distance to the stage, so a 85mm lens works mostly best.
My Zeiss Milvus Planar 1.4/85 offers me in that situation the following advantages compared to the older Nikkors like the 2.5/105, 1.8/85, 2/85, 1.4/85:
- much, much better performance (sharpness, resolution, contrast, 3D-rendering) at open aperture, and at 1 and 2 stops stopped down
- as you have a quite dim light, the possibility to use f1.4 with excellent sharpness and contrast is a real win, and allows using shorter shutter speeds as well
- another very important advantage: much, much better flare resistance of the modern Zeiss compared to the older Nikkors; with the strong spot-ligths on the stage flare can be a problem in such situations, and the Zeiss performs much better in that regard.

The Zeiss Milvus Planar 1.4/85 belongs to the best lenses ever built. It is a "Baby-Otus", as you get 95% of the Otus 1.4/85 performance, but at only 1/3 of the Otus price .
When I bought that lens I started comparison tests to all my other 85mm and 105 lenses, and the Milvus surpassed all of them.

I think everyone here knows Steve McCurry's most famous photo "Afghan Girl". That was shot with the also famous Nikkor 2.5/105. Those who have that Nikkor know it is really a very good lens, especially in the f4 to f8 range.
The 2.5/105 Nikkor has been my first portrait lens as a young student. I worked hard for it (significant amount of money for a poor student), and was very proud of then having and using it.
In one of my comparison tests I put both lenses on my Pixelschubse and started pixel peeping by zooming in to 100%: The Zeiss was already at f1.4 as sharp as the Nikkor at f4........three stops advantage, really amazing!
Means in practical daily photography that I can much more often use a slower, much higher quality film. The difference of Delta 100 vs. Delta 400, FP4+ vs. HP5+ or TMX vs. TMY-2 is very significant.

Best regards,
Henning

 

[blee1996]

Lens design and construction (huge advances in production of aspherical lenses, new improved glass types, tighter tolerances in manufacturing.....) has improved so much in the last decades.

There is another reason for the improvements: smartphone cameras. Lots of optical, mechanical, material and manufacturing innovations there to make the tiny 50MP sensors sing. Let alone the computational photography algorithms.

Leica and Zeiss benefit quite a bit from their collaboration with smartphone manufactures. So are some of the upcoming new lens brands out of Korea and China.

 

[Pioneer]

The weakest element is certainly in most cases the photographer. But nevertheless it makes sense to eliminate as many weak elements in the photographic chain as possible.



You should not concentrate on what brand is used. But whether you have a lens built to modern science and standards, or an old, outdated one.
The current Pentax 1.4/50 DFA and 1.4/85 DFA for example are much better than the former Leica and Zeiss 1.4/50 and 1.4/80 / 1.4/85 lenses which were designed in the seventies.
Lens design and construction (huge advances in production of aspherical lenses, new improved glass types, tighter tolerances in manufacturing.....) has improved so much in the last decades.

And these differences are huge, and are visible not only under ideal circumstances as you guess, but generally and in lots of different situations.

That is not the only weak element.

I do enjoy reading these posts and follow them regularly. However I have always been of the opinion that for a film user, these lenses may as well not even exist. On my LX, which is a very capable full-frame camera in its own right, I cannot use any of the lenses you have mentioned because the designers didn't think it was important to include manual aperture control. I haven't checked but I'm not even sure I can use one of these lenses on PZ1p, which does allow electronic aperture control. Since I rarely shoot digital, spending the money to purchase one of these behemoths over my very capable, though not as advanced, Pentax SMC-FA 50/1.4, which does include manual aperture control, is kind of like wasting my money. I think I am better off spending the money on a nice tripod.

 

[xkaes]

Argue all you want. I've never seen any actual evidence of providing 8x10" pictures to random people from top-quality lenses -- and showing any difference. Actually, I've seen lots of evidence to the contrary. You may see something under a microscope at a particular f-stop but that's not real life -- photographic or otherwise.

Do all the pixel-peeping you want, but I know my 6-foot murals from a 24mm Rokkor will be indistinguishable from any 24mm Leica.

 

[Film-Niko]

That is not the only weak element.

I do enjoy reading these posts and follow them regularly. However I have always been of the opinion that for a film user, these lenses may as well not even exist. On my LX, which is a very capable full-frame camera in its own right, I cannot use any of the lenses you have mentioned because the designers didn't think it was important to include manual aperture control. I haven't checked but I'm not even sure I can use one of these lenses on PZ1p, which does allow electronic aperture control.

As a Pentax user you are indeed unfortunately in a significantly worse situation compared to Canon, Nikon, Leica, Zeiss Ikon ZM and Voigtländer Bessa users (for the later dozens of new lenses are available).
As Pentax' market share had shrunk massively since the mid-eigthies, most independent lens manufacturers don't see a big enough market (anymore) to offer their lenses in K mount.
Pentax is a very small niche market today.

But nevertheless there are also several modern lens options for Pentax (film) SLR's:
- Sigma has offered its famous Art 1.4/35 lens until recently also in K mount (afaik in the KA mount version); it was just some months ago discontinued in K mount, so you can find it on the used market.
- Zeiss introduced their new SLR lens line (now known as "classic line") in 2006 with Canon EF, Nikon F and Pentax K mount. They stopped offering K mount some years later because of too low demand from Pentax users. But those that were produced are still on the used market, so you can look for the excellent Makro-Planars 2/50 and 2/100, or the 2.8/21, 2/25 and 2/28 Distagons.
- Irix is offering their lenses in KA mount, so you can use these lenses on older K-mount DSLR or SLR film cameras which have Tv and P mode, like your PZ1p.
- Meyer-Optik-Görlitz is offering all their lenses in classic K mount with aperture ring. So far they don't have high-performance lenses yet, but at least they have said that they intend to go into modern lens designs as well.
- Samyang is offering lots of lenses with K mount. Not the highest quality level, but some are very good.

 

[Film-Niko]

Argue all you want. I've never seen any actual evidence of providing 8x10" pictures to random people from top-quality lenses -- and showing any difference.

In one of your posts you said that the only direct comparison you made was between the old design Elmarit 2.8/24 to the old design Rokkor 2.8/24.
But you haven't done any direct comparison tests of any of the new and improved lenses.
If you don't use the modern lenses, you can't of course see anything.

I am using them, and see huge improvements. Otherwise I would not spend any money on them. Simple as that.

You may see something under a microscope at a particular f-stop but that's not real life -- photographic or otherwise.

I see the difference in my daily normal photography. With prints made in my darkroom, with slides, and in digital on the monitor.
That you could see only differences under a microscope is totally wrong.

Fact is that all lens manufacturers have made huge progress in the last decades, in design and construction/production.
They have given up the older designs because the new designs are much better. The customers see these improvements because they are very obvious, and the customers demand the improvements.
Otherwise the lens manufacturers would not spend millions in R&D, and upgrading the production. It would be disastrous for the producers if they were wasting so much money on products with no visible improvements. They would loose their customers immediately.

You are of course free to believe that there has not been visible progress in lenses in the last decades. As you are free to believe that modern motors have the same fuel consumption as 40 year old motors, or that modern cars have no safety advantages compared to 40 year old cars.......

 

[Hassasin]

Is this still about op[tics and how they have "improved" film shot photos? I hope not.

 

[Pioneer]

As a Pentax user you are indeed unfortunately in a significantly worse situation compared to Canon, Nikon, Leica, Zeiss Ikon ZM and Voigtländer Bessa users (for the later dozens of new lenses are available).
As Pentax' market share had shrunk massively since the mid-eigthies, most independent lens manufacturers don't see a big enough market (anymore) to offer their lenses in K mount.
Pentax is a very small niche market today.

But nevertheless there are also several modern lens options for Pentax (film) SLR's:
- Sigma has offered its famous Art 1.4/35 lens until recently also in K mount (afaik in the KA mount version); it was just some months ago discontinued in K mount, so you can find it on the used market.
- Zeiss introduced their new SLR lens line (now known as "classic line") in 2006 with Canon EF, Nikon F and Pentax K mount. They stopped offering K mount some years later because of too low demand from Pentax users. But those that were produced are still on the used market, so you can look for the excellent Makro-Planars 2/50 and 2/100, or the 2.8/21, 2/25 and 2/28 Distagons.
- Irix is offering their lenses in KA mount, so you can use these lenses on older K-mount DSLR or SLR film cameras which have Tv and P mode, like your PZ1p.
- Meyer-Optik-Görlitz is offering all their lenses in classic K mount with aperture ring. So far they don't have high-performance lenses yet, but at least they have said that they intend to go into modern lens designs as well.
- Samyang is offering lots of lenses with K mount. Not the highest quality level, but some are very good.

Thanks but I'm not even sure we are talking about film anymore. I looked up several of these lenses you mention and they will all work to some extent on digital Pentax cameras. But if you want to stop down the apertures you have to have electronic aperture control capability on your camera. I know the Pentax PZ1p can do this and most likely the Pentax MZ-S but those are the only Pentax film cameras that do this.

So basically, if I want to spend $1,000 dollars or more to shoot my lens wide open all the time, I can do that. These lenses have all been designed to work with electronic controls.

I have no idea what Nikon or Canon film camera users can work with, but for me these are basically digital lenses and are marginally useful, if at all, for film.

If I find a used one on a really, really, really good sale I may consider buying it...maybe.

On the other hand Voigtlander has actually built manual aperture control into their K-Mount lenses. I own a couple of them and they are terrific lenses. I am using one right now on a regular basis with my LX. There is a good chance I would buy more at some point in the future. They appear to be one of the few companies that are interested in catering to our "niche" film market.

 

[Film-Niko]

Is this still about op[tics and how they have "improved" film shot photos? I hope not.

I am talking about improving film photography by using better lenses.

That is what the modern designed lenses offer:
- better sharpness
- higher resolution
- higher contrast
- less flare by improved coatings and improved inner reflection avoiding measurements
- nicer, smoother bokeh
- less astigmatism
- often improved coma performance
- very often much improved mechanics
- often additional wheather / water and dust resistance by additional sealings
- often (e.g. with the Zeiss lenses) very nice separation of the in-focus to the out-of-focus details ("3D-Pop")
- often (e.g. Zeiss) excellent colour reproduction.

Almost all of the new top-quality lenses offer excellent performance even at full open aperture of f1.4 or f1.8 / 2.0.
None of the older lenses can do that.
Lots of the new lenses have at f1.4 a performance equivalent to older lenses stopped down to f2.8.
And lots of the new lenses have their 'sweet spot = optimal performance' at f2.8 to f4, whereas most older lenses have their sweet spot at f5.6 to f8.
So in most cases you gain two stops with the modern lenses, which means that you much more often can use an ISO 100 film instead of an ISO 400 film. Which makes a big difference in quality.

 

[Hassasin]

I am talking about improving film photography by using better lenses.

That is what the modern designed lenses offer:
- better sharpness
- higher resolution
- higher contrast
- less flare by improved coatings and improved inner reflection avoiding measurements
- nicer, smoother bokeh
- less astigmatism
- often improved coma performance
- very often much improved mechanics
- often additional wheather / water and dust resistance by additional sealings
- often (e.g. with the Zeiss lenses) very nice separation of the in-focus to the out-of-focus details ("3D-Pop")
- often (e.g. Zeiss) excellent colour reproduction.

Almost all of the new top-quality lenses offer excellent performance even at full open aperture of f1.4 or f1.8 / 2.0.
None of the older lenses can do that.
Lots of the new lenses have at f1.4 a performance equivalent to older lenses stopped down to f2.8.
And lots of the new lenses have their 'sweet spot = optimal performance' at f2.8 to f4, whereas most older lenses have their sweet spot at f5.6 to f8.
So in most cases you gain two stops with the modern lenses, which means that you much more often can use an ISO 100 film instead of an ISO 400 film. Which makes a big difference in quality.

Well, improving photography by changing lenses has not historically been proven as a solution ... to better photography. I suppose it is dependent of reference point too. Since top class photography is possible with a pinhole, one needs to go down the "pixel" road to discredit such a possibility.

I have noticed, which has been coming, that digital peeping into an image has drifted over to evaluating what is "good" in film image. Thus i.e. a Zeiss glass will always make better a photograph.

40 mpx sensor in Fuji's X-H2 does show improvement even with older Fuji lenses ... if peeped into it so deep, actual image is lost in its own wake.

 

[Film-Niko]

Thanks but I'm not even sure we are talking about film anymore.

Of course we are talking about film !

I looked up several of these lenses you mention and they will all work to some extent on digital Pentax cameras.

And on most film Pentax SLRs since 1983, since the introduction of the KA mount, which allows using shutter priority and program mode.
The Irix lenses I mentioned have KA mount.
The mentioned Zeiss ZK (classic line) lenses have K mount, so no problems even with older Pentax film SLRs.
Meyer-Optik-Görlitz also offers K mount.
And the Samyang lenses afaik is also KA mount.

I have no idea what Nikon or Canon film camera users can work with, but for me these are basically digital lenses and are marginally useful, if at all, for film.

Canon EF users are in the perfect position, as they can use all mentioned lenses as all are offered in EF mount.

Nikon users can use all Zeiss Otus, all Zeiss Milvus, all Zeiss ZF / ZF.2 (classic line), all Voigtländer SL-II, all Irix and all Meyer-Optik-Görlitz lenses.
And the following Sigma Art lenses can also be used without any limitations: Art 1.4/35, Art 1.4/50, Art 2.0/24-35 (a zoom lens with real prime lens quality) and Art 4/24-105.

On the other hand Voigtlander has actually built manual aperture control into their K-Mount lenses. I own a couple of them and they are terrific lenses.

Voigtländer lenses with Pentax K mount. That was many years ago, unfortunately. Their SL-II SLR lens line is for years now only available with Nikon F mount.

 

[Sanug]

I owned the Pentax LX in the 1990s. The optical and mechanical quality of the Pentax K, M and A series lenses was very satisfying for me. I never had the need to go for a better quality.

My highlights from the SMC Pentax Range:

K 3,5/18
K 1,2/50
K 1,8/85
K 2,5/135
K 2,5/200
A* 4/300

I shot a lot of available light stage images with great success.

There is one point why the Leica R might be a bit superior. This is not because of the lenses, but the R bodies include a very sophisticated mirror slap damping. This may lead to sharper images due to reduced shaking.

 

[Film-Niko]

Well, improving photography by changing lenses has not historically been proven as a solution ... to better photography. I suppose it is dependent of reference point too. Since top class photography is possible with a pinhole, one needs to go down the "pixel" road to discredit such a possibility.

Come on, that is not the topic here at all! That is a truism / tedium / Binsenweisheit.
You can say the same to people who are using medium format and large format, that using the larger format will not be a solution to better photography.
We all know that we can make technically excellent pictures with our best lenses, best 35mm, medium and large format cameras, which could nevertheless look boring.
That is not the point at all.

But a well composed picture, or a picture with a clever idea, looks much more appealing if it is made in a technically better way compared to the lower quality way.
People who enjoy it in a different way can use pinhole cameras or Lomography toy cameras, as you like it. Nothing wrong with that.
But not the topic here!

 

[Pioneer]

Of course we are talking about film !



And on most film Pentax SLRs since 1983, since the introduction of the KA mount, which allows using shutter priority and program mode.
The Irix lenses I mentioned have KA mount.
The mentioned Zeiss ZK (classic line) lenses have K mount, so no problems even with older Pentax film SLRs.
Meyer-Optik-Görlitz also offers K mount.
And the Samyang lenses afaik is also KA mount.



Canon EF users are in the perfect position, as they can use all mentioned lenses as all are offered in EF mount.

Nikon users can use all Zeiss Otus, all Zeiss Milvus, all Zeiss ZF / ZF.2 (classic line), all Voigtländer SL-II, all Irix and all Meyer-Optik-Görlitz lenses.
And the following Sigma Art lenses can also be used without any limitations: Art 1.4/35, Art 1.4/50, Art 2.0/24-35 (a zoom lens with real prime lens quality) and Art 4/24-105.



Voigtländer lenses with Pentax K mount. That was many years ago, unfortunately. Their SL-II SLR lens line is for years now only available with Nikon F mount.

Thanks. I will certainly look into some of that Zeiss glass. I am not dissatisfied with the Pentax options, they are very, very good, but it is fun to try something a bit different from time to time.

And it has been a long time since I picked up a new lens from any manufacturer.

I agree with Sanug and even though I have no intention of ever giving up my Pentax gear I may even look into a Leica SLR for the fun of it. I wonder if I can rent one from somewhere.

 

[removedacct3]

I owned the Pentax LX in the 1990s. The optical and mechanical quality of the Pentax K, M and A series lenses was very satisfying for me. I never had the need to go for a better quality.

My highlights from the SMC Pentax Range:

K 3,5/18
K 1,2/50
K 1,8/85
K 2,5/135
K 2,5/200
A* 4/300

No SMC 28mm F2?

 

[Pioneer]

But a well composed picture, or a picture with a clever idea, looks much more appealing if it is made in a technically better way compared to the lower quality way.
People who enjoy it in a different way can use pinhole cameras or Lomography toy cameras, as you like it. Nothing wrong with that.
But not the topic here!

I don't agree with this at all. Dorothea Lange's work and Eugene Atget's work, to name only a couple, are not revered for their' "technical excellence" and believing that those pictures would be better if they were somehow captured with a technically better lens is a false premise. Once in awhile I wonder what film, lens or camera Ansel Adams used to shoot one of his photographs but I don't look at any of them believing it would have been better if he would used a technically better optic.

I do enjoy nice lenses but I have never believed that they are in any way a substitute for good composition. Fortunately for most of us owning the very latest in technology is not a prerequisite to good photography.

 

[MattKing]

To my mind, it isn't a matter of whether newer and "better" lenses give you better photographs - they very, very, very rarely do.
Save and except for very specific uses, such as extreme enlargements, or photographs that demand technical qualities, such as aerial photography for scientific use.
Sometimes though, the improved lenses offer performance that helps save a photograph - i.e. make it useful and usable - in difficult conditions like high flare situations.
Sometimes they also offer great light gathering performance as well, which also helps save a photograph - i.e. make it useful and usable. Fast lenses can also be very pleasant/satisfying to use with TTl viewing systems, due to how bright the image is and how narrow the depth of field is.
Sometimes they incorporate excellent ergonomics and wonderful fit and finish - that at least can increase enjoyment with use.
But in general, after more than half a century of using a very wide variety of lenses, I can count on one hand the number of times that I obtained an unsatisfactory result due to the lack of quality in a lens - and every one of those cases was due to the fact that the sub-standard lens fell apart - a mechanical shortfall, not an optical one.

 

[Sanug]

No SMC 28mm F2?

I don`t remember if I owned the 2/28 or the 2/35. It was a good lens. Too bad that I sold all analogue equipment.

Now I am happy with the underdog Praktica. Ok, it has a heavy mirror slap, but the MTL 5 is a bargain, and the east german DDR Zeiss Jena lenses are very good.

And with M42 the system is open to many good lenses of differend brand. Asahi Pentax Takumar as well.

 

[Mark J]

..... from someone who worked in the past as lens designer....

Don't count me out yet ! - still going, 35 years, going on 36 in November

 

[Mark J]

I just came back from a terrible week in the Lake District ( England ) , hardly anything taken, the weather was awful ... even by UK standards.
Catching up on a few points -

The Leica 24/2.8 R was a lens that disguised its faults very well, on paper it shows loss of detail resolution in the mid-field , but because it was very good in the corners, and the 10cy/mm and 20cy/mm contrast were very high across the field, it always looked very snappy and satisfying on slide film whenever I used it. I'm sure you would see some shortcomings on modern 20MPix+ sensors nowadays though. It's always been overpriced in the Leica version though - I hesitated at buying a used copy in the 90's, it was £800 equivalent back in 1998. I wanted to use it recently on my Canon 5D/II but unfortunately it's one of a few 'R' lenses that don't clear the reflex mirror when adapted.
I'm with Henning as regards the quality of the late-80's/& 90's lenses though, there was a big step up in ambition and performance when Lothar Koelsch came in, almost all of those designs are competitive with the best nowadays. I had the brief pleasure of taking some shots with the 280mm f/4 at a Leica day at our local shop, I was lucky enough to have one of my last rolls of Kodachrome 25 in the camera. The quality was as good as it gets, right across the frame, at f/4. Shame it's not such a useful focal length ... except for sports ...
However for sports the autofocus lenses have really made it a lot easier in practical shooting though.
I have the 80-200 f/4, the optical quality is exceptional, but you really need a tripod to focus it once over 135mm focal length ( the focus gets more sensitive, as with all front-focusing optics ). I have to say that my Canon 135 f/2 gets more use.

The 50mm f/1.4 E60 lens may not reach the sharpness levels of the latest mega-optics in that spec, but it is probably the best 'compact' 50mm f/1.4 out there, and that often matters. Shame about the price though !

In all of this, I have no axe to grind about what people should use, and whether they can get great photos with other kit. In fact it's quite hard to find a sub-group for whom Leica R is the answer, nowadays. I often recommend the late Zeiss ZE/ZF/ZK lenses if people want a quality manual-focus optic.
However I do really like the bodies for film shooting.

 

[Film-Niko]

I don't agree with this at all. Dorothea Lange's work and Eugene Atget's work, to name only a couple, are not revered for their' "technical excellence" and believing that those pictures would be better if they were somehow captured with a technically better lens is a false premise.

That is not what I have meant. Maybe or probably I was not precise enough.
If I look at my pictures in comparison, so when I have made the exact same shot on parallel with both my best new lenses, and my older design lenses (for comparison purposes), then those made with the newer ones look much more appealing, have more emotional impact.
Depending on the subject that is caused by
- the better detail rendition
- much nicer, smoother bokeh
- better isolation of the focussed subject (better three-dimensional impression; a strength of the modern Zeiss optics especially)
- better emphasis on the main subject with much improved wide aperture performance: e.g. your subject looks much better when it is really sharp and has good contrast at f1.4, and it is much better separated from the unsharp background
- the possibility now even shots made with open aperture to enlarge to big, wonderful prints or project largely on a screen (the former lenses lack sharpness, resolution and contrast at open aperture, and often even (of course to a lesser extent) 1-2 stops stopped down - and on bigger enlargement that really does not look good).

 

[Film-Niko]

Don't count me out yet ! - still going, 35 years, going on 36 in November

Sorry, that was not my intent at all ! It was just my information given by your statements so far. Good to hear you are still active as a lens designer. May I ask in what field of optic design you are currently working?

 

[Alan Edward Klein]

A good friend of mine ( Reg Jonas ) was head of optics at Midland for many years until he retired recently. I myself also went for an interview at Leica in Solms in 1997 before joining Zeiss instead. On both counts I can confirm that Leica designed and built their own lenses. The only exception I can think of is the R 24/2.8 which was a design shared by Leica and Minolta, starting in the 70's. Having owned both versions, the Leica one was much better, I assume because of the tighter tolerances, but also the better coatings this 1990's example had compared to the older MC 24/2.8 I had. Leica R lenses were exceptional in their time in the 70's/80's & early 90's , though they have been surpassed in recent years by many lenses for modern 20+ Mpix applications. In their time their strong points were better stray light control and colour saturation, and exceptional consistency around the FOV resulting from their tighter tolerances ( this is confirmed by tests in Color Foto magazine, if you can find back-issues ) .
Leica also made their own glass for many years, in the Wetzlar area, they had some very high index lanthanum flints and a couple of unique borate flints ( KZFS ) than nobody else had access to.

What's a high index lanthanum flint and what does it do?

 

[Film-Niko]

To my mind, it isn't a matter of whether newer and "better" lenses give you better photographs - they very, very, very rarely do.
Save and except for very specific uses, such as extreme enlargements, or photographs that demand technical qualities, such as aerial photography for scientific use.

From my own experience with the newer, much improved lenses I have to disagree. Because the better lenses offer me many different advantages in many different fields and different shooting situations (as explained in my postings above)

Sometimes though, the improved lenses offer performance that helps save a photograph - i.e. make it useful and usable - in difficult conditions like high flare situations.
Sometimes they also offer great light gathering performance as well, which also helps save a photograph - i.e. make it useful and usable.

It is even more than that: The performance of lots of these new lenses at open aperture and slightly stopped down is so good that the results look amazing, and are much more than "useful".
And by that you can also really exploit the artistic potential of very small DOF and excellent subject isolation.

Fast lenses can also be very pleasant/satisfying to use with TTl viewing systems, due to how bright the image is and how narrow the depth of field is.
Sometimes they incorporate excellent ergonomics and wonderful fit and finish - that at least can increase enjoyment with use.

Absolutely. The also much improved production quality and mechanical quality including (often) weather sealing is a great advantage, too.