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10-29-2017, 12:20 AM   #31
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QuoteOriginally posted by Ranchu Quote
They make/made single coated and multicoated lenses.
There are examples of old uncoated* Voiugtalnder, Zeiss,Schneider and Leica lenses - Some of them are so popular they are updated and made with current optical coatings.

*or lenses with single coatings, magnesium fluoride was common AR coating used on early mass produced lenses . However MgF2 coating was fragile, simply rubbing it with a coarse material was sufficient to remove it, Its performance was also variable depending on which glass type it was applied to.


Last edited by Digitalis; 10-29-2017 at 12:26 AM.
10-29-2017, 01:00 AM   #32
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Of course there are examples from the days when uncoated lenses were the only kind there were, what you said was that Voigtlander 'make both uncoated and uncoated' lenses. Cosina Voigtlander make/made single coated and multicoated versions of the same lens concurrently. Voigtlander, Zeiss, and whatever haven't made uncoated lenses since before WWII.
QuoteQuote:
Not really. Voigtlander make uncoated and uncoated lenses: they are by necessity simple optical designs and the difference between them is an improvement in contrast but resolution is fundamentally identical.

Last edited by Ranchu; 10-29-2017 at 01:07 AM.
10-29-2017, 04:51 AM   #33
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QuoteOriginally posted by Ranchu Quote
Voigtlander, Zeiss, and whatever haven't made uncoated lenses since before WWII.
Some Uncoated lenses post WWII were still in production, as there were still adherents who held that uncoated optics had a "look" that was lost as soon as coatings were used on lenses*. It was only until the 1960s and the progressive rise of Japanese mass manufacturing that lens coatings technology really took off.

*Uncoated lenses have a glowing, unsharp look, this was very popular during the early hollywood days for actors headshots. Presumably this was because editing out blemishes was difficult to do at the time and time consuming, Lightsources used for portraiture were primitive compared to today. For photography in those days light output levels had to be very high and often produced very hard and contrasty light.

Last edited by Digitalis; 10-29-2017 at 05:04 AM.
10-29-2017, 06:37 AM   #34
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I have not read through all of the comments, and there's a high risk of repeating some observations already made:
1) In terms of IQ, newer zoom lenses are undoubtedly superior to the majority of those introduced during the film era.
2) more widespread use of ED glass, and sometimes molded aspheric elements, also means that generally modern SFL telephoto lenses have better IQ than their film-era counterparts, but there are many exceptions (from Pentax, the 200mm SMCA macro and the 600mm F4 AF are about as good as any lens of similar FL and function).
3) It is my impression that newer lens designs, on the whole, do better maintaining IQ at the edges of the frame compared to older lenses.

Three further notes:
1) Using slide/chrome film, always considered superior to color negative film, in the vast majority of cases meant no cropping. Because of that, the equivalent of "pixel peeping" was not done. The entire image was evaluated, not the rendering of small details.Minor edge softening or corner vignetting was sometimes considered good, as it would emphasize the central image which was the subject.
2) Truly great images - enduring, iconic, stunning, memorable after one glance - have been taken back into the 1800's with everything from 20X24 view cameras to the original pre-war Leica "miniature" camera, sometimes with lenses as basic as an uncoated Cooke triplet. Equipment helps, but the ability of the person tripping the shutter really determines the quality of the image.
3) In terms of lens design, to blow this horn yet again, the four-element Zeiss Tessar remains one of the greatest breakthroughs. A well-made Tessar of modest aperture (not wider than f2.8) and focal length (not far from normal FL for any given format) has IQ competitive with many vastly more complex lens designs. A well-made reverse Tessar can record excellent to outstanding macro images (witness the original 50mm f4 macro Takumar).

10-29-2017, 08:43 AM   #35
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QuoteOriginally posted by stevebrot Quote
Addendum: Certain current emulsions claim much higher resolution than what was available from Technical Pan.
Adox claims their CMS20 can do "up to 800 lp/mm":

ADOX | CMS 20 II & ADOTECH III

http://www.adox.de/Technical_Informations/CMS20_ADOTECHII_instructions.pdf

Phil.
10-29-2017, 09:28 AM   #36
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QuoteOriginally posted by Digitalis Quote
Some Uncoated lenses post WWII were still in production, as there were still adherents who held that uncoated optics had a "look" that was lost as soon as coatings were used on lenses*. It was only until the 1960s and the progressive rise of Japanese mass manufacturing that lens coatings technology really took off.

*Uncoated lenses have a glowing, unsharp look, this was very popular during the early hollywood days for actors headshots. Presumably this was because editing out blemishes was difficult to do at the time and time consuming, Lightsources used for portraiture were primitive compared to today. For photography in those days light output levels had to be very high and often produced very hard and contrasty light.
Zeiss first coated lens elements in 1935, and Kodak didn't start to coat lenses until ca. 1938. However, as early as the 1890's experiments started to take place for coating lenses.

The soft look in movies, especially for women was achieved because of the lens design, not the coating. Cinematic lenses came in a couple of versions. There were fairly sharp lenses, and they were used for male actors, and in scenes in which actors and actresses appeared together. Women, however, were frequently shot with lenses containing a lot of chromatic aberration. This "flaw" in lens production yielded the soft, glowing, image that actresses sought. You can still buy lenses from companies like Cooke, which will yield the soft focus some portraitists like. The modern designs, such as Mamiya's 150mm f4 use diffusion discs, and they don't yield quite the same results.
10-29-2017, 03:40 PM - 2 Likes   #37
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QuoteOriginally posted by stevebrot Quote
PF member Nesster has a Modern Photography article from the mid-1980s on his Flickr photostream where attempts were made to extract 100 lp/mm from lenses (all fast-50s) and films available at that time. IIRC, that number proved illusive. I will see if I can find it and post it here if I do.
I found it! Reading from a larger copy at Flickr is easier, so click through on the link and/or the full resolution link I am providing.




Higher Resolution versions of "How Sharp Can You Get?", p1





Higher Resolution versions of "How Sharp Can You Get?" - continued


The entire article, despite dating to the early 1980s, is pertinent to the technical aspects of this discussion as well as to best-case user expectations. Of particular interest is methodology for determining captured resolution. Note that from a selection of available lenses from the major vendors, the Pentax-M 50/1.7 made the cut over faster offerings. The same was true across the board with nothing faster than f/1.7 in the test. Here are a few of the highlights:
  • The only color film to deliver 100 l/mm was Micro-Ektachrome
  • No emulsion intended for general pictoral photography was able to deliver 100 l/mm with any of the lenses surveyed
  • No the Pentax 50/1.7 did not sweep the field; that honor went to the Leitz Summicron 50/2
  • No, dedicated macro lenses did not outperform any of the fast 50s, even for close focus
  • Focus bracketing was required for all lens/camera combinations
My favorite paragraph runs as follows:
QuoteQuote:
To understand why we could not readily get 100 lines per mm using Panatomic-X film, we looked at the MTF (Modulation Transfer Function) curves available from Eastman Kodak for their films. These MTF curves gave us an idea of how good the lens would have to be in terms of image sharpness to yield 100 lines per mm on film. Panatomic-X film exhibits a modulation (contrast) of about 40 percent at 100 lines per mm. If we assume that we need at least 20 percent contrast to barely resolve two lines close together on the film, the image formed by the lens has to deliver at least 50 percent contrast at 100 lines per mm. Well, this sounds easy. However, if the lens is operating at f/5.6, then the theoretical limit of resolving power is around 320 lines per mm. And even if the lens is perfect, the contrast at 100 lines per mm is only about 60 percent. The slightest error in focusing quickly reduces this 100-lines-per-mm contrast to below 50 percent even with the perfect lens. From the results we obtained, it appears that most of the lenses we tested came pretty close to optical perfection at f/4 or f/5.6. But since we are working so close to the theoretical limits imposed by MTF and resolution, reaching 100 lines per mm on film is quite difficult. (emphasis mine...SB)
But wait! There's more!

As noted above, the Summicron 50/2 performed the best in the testing. That same lens (1979 version) has been tested at what used to be photozone{.}de (now opticallimits{.}com) on the Leica M9 (18Mpx FF). The center resolution results...

f/2.8 -- 3096 lw/ph (129 l/mm)
f/4 -- 3265 lw/ph (136 l/mm)
f/5.6 -- 3228 lw/ph (135 l/mm)
The Summicron 50/2 did somewhat better with an 18 Mpx sensor than on 35mm film despite observed focus shift on stop-down. I could not find whether their test method includes focus bracketing.

Now, the bad news...

Nikkor AF-S 50/1.8 G on the 24 Mpx D3x @ f/5.6 -- 3958 lw/ph (165 l/mm)
Canon EF 50/1.8 STM on the 21 Mpx 5DII @ f/5.6 -- 3742 lw/ph (156 l/mm)
Ummm...the Summicron is running a bit behind a couple of recent consumer grade lenses. Granted, both were run against somewhat higher resolution sensors, but still those numbers are sobering.

But...but...but...Those differences in sensor pixel count are important. Consider the theoretical maximum for each:

Leica M9 -- 3472 lw/ph (145 l/mm)
Nikon D3x -- 4032 lw/ph (168 l/mm)
Canon 5DII -- 3744 lw/ph (156 l/mm)
Normalizing to percentage of theoretical maximum, it is quite likely that all three lenses are sensor-limited on the test cameras.

Conclusion?
The value proposition for moderate focal length primes has never been better. For example, the Canon EF 50/1.8 STM also outperformed the Sigma 50/1.4 DG HSM (Art). In addition, while evidence is hard to come by, the rare objective test and numerous example images tend to indicate that many older lenses continue to perform at or near the theoretical limits for the sensors they are paired with.

With zooms, it is somewhat more difficult to make similar claims. Objective tests for zooms released more than about 15 years ago are hard to come by. What's more, it is pretty much established dogma that all but the newest zooms are troublesome junk and not worth shooting with. I would tend to agree except that I have done some decent work recently with the Pentax-A 70-210/4 on the K-3...go figure


Steve
10-29-2017, 03:52 PM   #38
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But I donít carry a 100kg block of ferroconcrete around with me to attach the camera 2! So the performance of the AV capability or the photographer is more critical than lens?

10-29-2017, 04:02 PM   #39
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QuoteOriginally posted by Xmas Quote
But I donít carry a 100kg block of ferroconcrete around with me to attach the camera 2! So the performance of the AV capability or the photographer is more critical than lens?
Excellent!

I came across an interesting statement from Klaus on what was photozone that they did not test a particular lens on the Sony A7R because the shutter vibration on that camera was so wretched that they could not get good results for lenses that they knew were good.


Steve
10-29-2017, 05:31 PM   #40
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QuoteOriginally posted by stevebrot Quote
I found it! Reading from a larger copy at Flickr is easier, so click through on the link and/or the full resolution link I am providing.
Steve
It's great that you found the MP testing links. It doesn't say how many copies of each lens they tested. Maybe more than one or assume that each is as good as the other?

Although I proved from my results using Kodak Techpan - with my copy of Pentax-M SMC 50mm f4 macro lens, that it does outresolve even the latest sensors on film - satisfying the OP's question, I did not show the results from the lenses on the OP's list. I do have the Pentax-M 50mm F1.4 and I am sure I also tested it in the same manner. Now it's just a matter of getting it.

Of course all I have are used lenses so I am not sure just how close it is to it's original performance.
10-29-2017, 08:55 PM   #41
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QuoteOriginally posted by LesDMess Quote
Although I proved from my results using Kodak Techpan - with my copy of Pentax-M SMC 50mm f4 macro lens, that it does outresolve even the latest sensors on film - satisfying the OP's question
First off, I want to tell you how much I respect the huge library of photo-associated visuals you have generated and share with the users on this site. I hope you don't take any of the below as criticism.

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

I have puzzled over that graphic more than once over the years* and my interpretation has been that it has:
(Courtesy LINK to full-sized JPF of the graphic)
  • Four crops of digitized optical copies of a Tech Pan negative, two at 1x (D800 and scanner), one at 0.67x (K20D), and a fourth at 4.5x (also K20D)
  • The full image for the first three would have been of the full 24x36 Tech Pan negative. The last (4.5x mag) would have included mostly the area of interest.
  • The amount of detail captured for each crop may be ranked in the order 0.67x (K20D) < 1x (D800) < 1x (4000 DPI scanner) < 4.5x (K20D)
  • 1:1 mapping of "dots" to pixels assumed for the scanner
  • Variables include pixel efficiency for the capture, quality of optical system, and presentation of the negative (lighting, flatness, alignment)
I called out the magnification because it is equivalent to applying a microscope to create the image. The higher the magnification, the more we might see...regardless of whether we do or not.

From the information presented, I would choose the scanner for a full-frame copy over the other methods. I also note that none of those methods captured the full detail of the negative and that it is possible that a magnification other than 4.5x might equal or better that case (e.g. 1.5x or 20x or whatever).

What I am unable to do is infer how much detail was captured on the negative itself. To estimate that I would need the pixel efficiency of the system (optics, image processor, presentation, etc.) so I would have a notion of how much was not "seen". The D800 is a good example in that its rank should have been above the scanner for a 1x full-frame copy based on capture resolution alone. Was there a focus problem? Optical field curvature? Loss due to Bayer interpolation? I dunno.

To be honest, I would not expect any of the systems to fully replicate even a Kodak Gold 200 negative. There is always sampling loss. The same is true for an optical enlargement, a projected image, a contact print, or even direct microscopy.

FWIW, it would have interesting to see if the D800 and the K20D were equivalent at 1x (similar pixel pitch).


Steve

* I had seen it before as example in the past on other threads.
10-30-2017, 11:31 AM   #42
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I am still trying to get a feel for the margin between the film MTF curve and what is needed in typical hand held photos.

This photo was with the Ricoh KR-5, Fuji Superia 200 35mm and the SMC Pentax 1:2.8 40mm
The photo .tiff is of lettering on a sign so has lots of edges in it.
The Fuji film rolls off at approximately 40 per millimetre.
The scanner was set to a resolution corresponding to 62.5 lines /mm.

https://app.box.com/s/rrk6aeilqci7mj1wftzsr40vob83ktib

Here is the harmonic content in the photo:
The harmonics are in 16 bit format, so the high order ones are "blocky"
Next time I will put them in floating point.
https://app.box.com/s/7gdxro7wry7y5vxs1gpvkoib7s9gklg8
10-30-2017, 01:48 PM   #43
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Here is a photo taken with the Pentax K_S1 and the XR Rikenon 1:3.5 28mm
It is a camera jpg of 3072 pixels wide, so the resolution is almost the same
as in the Fuji 35mm film photo of my post # 42 (65 cycle/mm)
https://app.box.com/s/joquvzcy7hwldyhja53kl7x6lehukr8v

Here is the RGB harmonic content of the digital camera vs cycle/mm
https://app.box.com/s/lvfx0nbohefby6q74qgzqd59yx9dgd5d
10-30-2017, 02:27 PM   #44
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Aside from all the theory, there is a new thread on the Leica users forum where a user compares picture results from an early 1926 Leica model A (the first successful 35mm still camera) and its original Elmar 50 mm f3.5 uncoated lens, using Portra 160 film, to a Leica M10 (24mp) camera with modern lens. Not pixel-peeping, but the pictures from the 1926 lens compare quite favorably under his shooting conditions and use.
10-30-2017, 02:32 PM   #45
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QuoteOriginally posted by TomB_tx Quote
Not pixel-peeping, but the pictures from the 1926 lens compare quite favorably under his shooting conditions and use.
Yes, This one is from a 1936 Zeiss Ikon Nettar: (posted before)
https://app.box.com/s/2vvkg62b2gt3lavig368
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