awilder
Alan Wilder
I've recently acquired good examples of the Rollei 35 and 35 S and decided to test them both critically with ISO 200 color negative film (the slowest commonly available due to the popularity of digital). My shooting is usually snapshots and landscapes so I restricted my testing to shooting distances of 2 meters and infinity. The 2 m tests were done with a sturdy tripod and 1954 USAF style resolution charts along with Norman Koren's MTF 40 contrast test charts and infinity testing was done with some houses at a distance from my backyard.
Results were surprising in some respects and not in others. At 2 meters centrally, the Sonnar delivers outstanding contrast and resolution at all stops compared to the Tessar especially from f/4 and smaller. Quality is on par with the best Leica lens I once owned. Centrally, the Tessar is very good, just not quite as good as the Sonnar. That said, I supect centrally the Tessar is actually an even better performer than my test indicated because setting the focus slightly past 2 m improves center sharpness at the expense of mid-frame performance.
Moving off axis to the mid-frame (midway between the center and edge), the Tessar's resolution of fine detail is a llittle better than the Sonnar until f/8. The Tessar's sharpness here is actually better than it's center which remains virtually unchanged regardless of aperture. The Sonnar is respectably sharp but at settings of f/5.6 or smaller and it catches up to the Tessar at f/8. The culprit is uncorrected astigmatism in the mid and outer zones causing fine details to appear a little bit smeary. The Tessar also has some astigmatism but mostly confined to the edge and corner.
Along the edge and corner, both appear to behave the same at matching apertures.
Infinity settings were similar in performance to 2 meters.
The Sonnar's performance was confirmed in a brochure showing the MTF 40 graph of the Rollei 40/2.8 Sonnar when the Rollei 35 RF was introduced years ago as seen here: http://www.rangefinderforum.com/forums/attachment.php?attachmentid=44196&d=1177382651, indicating my sample is a typical example. I would liken the Sonnar's peformance the pre-asphreric 50 Summilux-M which also has high central zone sharpness but moderate astigmatism in the mid-field and outer frame when the subject is along a flat plane. Fortunately, a curved subject plane mitigates the astigmatic effect so it's practically nil. This probably gives the Sonnar it's unique German optical signature compared to the Japanese contemporaries in the 70's that were Tessar and symmetrical Gauss designs.
In terms of practical use, the Rollei's 40/3.5 Tessar is ideal for flat field landscape and general use where sharpness across most of the frame is critical. A good example would be a city skyline image. The 40/2.8 Sonnar would be ideal if a faster aperture is needed with high central zone sharpness or the subject(s) of interest is located in a curved plane as in a more 3 dimensional arrangement. Also, unless you are a good distance estimator or using a rangefinder, most photographers having these scale focus cameras are using small enough apertues to cover any focusing errors which would also take care of the astigmatic aberration as well.
Results were surprising in some respects and not in others. At 2 meters centrally, the Sonnar delivers outstanding contrast and resolution at all stops compared to the Tessar especially from f/4 and smaller. Quality is on par with the best Leica lens I once owned. Centrally, the Tessar is very good, just not quite as good as the Sonnar. That said, I supect centrally the Tessar is actually an even better performer than my test indicated because setting the focus slightly past 2 m improves center sharpness at the expense of mid-frame performance.
Moving off axis to the mid-frame (midway between the center and edge), the Tessar's resolution of fine detail is a llittle better than the Sonnar until f/8. The Tessar's sharpness here is actually better than it's center which remains virtually unchanged regardless of aperture. The Sonnar is respectably sharp but at settings of f/5.6 or smaller and it catches up to the Tessar at f/8. The culprit is uncorrected astigmatism in the mid and outer zones causing fine details to appear a little bit smeary. The Tessar also has some astigmatism but mostly confined to the edge and corner.
Along the edge and corner, both appear to behave the same at matching apertures.
Infinity settings were similar in performance to 2 meters.
The Sonnar's performance was confirmed in a brochure showing the MTF 40 graph of the Rollei 40/2.8 Sonnar when the Rollei 35 RF was introduced years ago as seen here: http://www.rangefinderforum.com/forums/attachment.php?attachmentid=44196&d=1177382651, indicating my sample is a typical example. I would liken the Sonnar's peformance the pre-asphreric 50 Summilux-M which also has high central zone sharpness but moderate astigmatism in the mid-field and outer frame when the subject is along a flat plane. Fortunately, a curved subject plane mitigates the astigmatic effect so it's practically nil. This probably gives the Sonnar it's unique German optical signature compared to the Japanese contemporaries in the 70's that were Tessar and symmetrical Gauss designs.
In terms of practical use, the Rollei's 40/3.5 Tessar is ideal for flat field landscape and general use where sharpness across most of the frame is critical. A good example would be a city skyline image. The 40/2.8 Sonnar would be ideal if a faster aperture is needed with high central zone sharpness or the subject(s) of interest is located in a curved plane as in a more 3 dimensional arrangement. Also, unless you are a good distance estimator or using a rangefinder, most photographers having these scale focus cameras are using small enough apertues to cover any focusing errors which would also take care of the astigmatic aberration as well.
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Ljós
Well-known
Hi, thanks for your effort!
I just made a much, much more basic test with a 35 TE and a 35S (and Summaron 35) on the same roll of TMY2... coming to the conclusion that both the Tessar and the Sonnar are absolutely sharp and good enough for my purposes
If I may ask, what was your protocol for making sure the Rolleis were accurately focused? Did you focus bracket and pick the negatives with the sharpest center?
I am asking because you make detailed statements about center versus edge sharpness... and you would of course have to make sure that your findings were not simply biased by the focus being off and, for example, the apparent edge sharpness of the Tessar being an effect of curvature of field etc.
Sincerely curious how you did it! Thank in advance for your answer, Ljós.
I just made a much, much more basic test with a 35 TE and a 35S (and Summaron 35) on the same roll of TMY2... coming to the conclusion that both the Tessar and the Sonnar are absolutely sharp and good enough for my purposes
If I may ask, what was your protocol for making sure the Rolleis were accurately focused? Did you focus bracket and pick the negatives with the sharpest center?
I am asking because you make detailed statements about center versus edge sharpness... and you would of course have to make sure that your findings were not simply biased by the focus being off and, for example, the apparent edge sharpness of the Tessar being an effect of curvature of field etc.
Sincerely curious how you did it! Thank in advance for your answer, Ljós.
damien.murphy
Damien
Interesting conclusion, and good to know. I'm a 35T user myself, and fall firmly into the last group of users you mention - those who use small apertures to cover any focussing errors, and use the Rollei as a sunny day camera.
Would be interested in hearing how you felt the sonnar and tessar reacted to colour, and also any differences in which they rendered..
Would be interested in hearing how you felt the sonnar and tessar reacted to colour, and also any differences in which they rendered..
Ljós
Well-known
Ah, one more thing: did you find a difference in effective focal lenght? My testing was, as I said, much less methodical, but it would appear to me that the Tessar is a teenie bit wider than the Sonnar.
All in all I am kicking myself that I did not try the Rollei 35 earlier - I really like the experience, for when I am not carrying a M2. Only gripe are the "upside-down" negatives, and the uncorrected parallax/laterally offset viewfinder.
Greetings, Ljós
All in all I am kicking myself that I did not try the Rollei 35 earlier - I really like the experience, for when I am not carrying a M2. Only gripe are the "upside-down" negatives, and the uncorrected parallax/laterally offset viewfinder.
Greetings, Ljós
chris00nj
Young Luddite
Very cool analysis.
It's funny that people pay top dollar for a Tessar over a triplet when it's on a TLR or MF folder, but on a Rollei 35, prices would indicate that the Tessar is unvalued.
It's funny that people pay top dollar for a Tessar over a triplet when it's on a TLR or MF folder, but on a Rollei 35, prices would indicate that the Tessar is unvalued.
The Tessar on a Rollei 35 goes for more than a Triotar.
I have the Tessar, and it is certainly good enough. I think error due to scale focus in normal use is going to make actual differences "in the noise".
I have the Tessar, and it is certainly good enough. I think error due to scale focus in normal use is going to make actual differences "in the noise".
awilder
Alan Wilder
Focus accuracy was confirmed as fairly correct bracketing focus test shots. The Sonnar is a bit more sensitive to focus errors due to it's speed. One reason 2 meters was selected for the test charts was that it's easy to set on the scale and it's a typical snapshot distance. I didn't compare color rendition but both lenses appear free of any chromatic aberrations. An important take away point is that to get the most out of these incredibly sharp lenses, an accessory rangefinder is needed to ensure really sharp images, especially at medium to close distances with anything faster than f/8.
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John Robertson
Well-known
My B35 with Triotar was very very sharp, relly surprised me!!!
awilder
Alan Wilder
Here are two prime examples of pictures taken with my previous Rollei 35 SE with the 40/2.8 Sonnar. Because the subject matter was at a relatively long distance, rangefinder focusing was not required and astigmatic blur was held to a minimum with a medium aperture selection.
Attachments
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Edward C. Zimmermann
Nerd
The Tessar is not undervalued. German made Rollei 35--- the original with Tessar or Xenar-- is over-valued compared to the later models. Only the Xenar model is rare. More than twice as many "made in Germany" Rollei 35 models were made as the (made in Singapore) Rollei 35SE.
The discussion Sonnar versus Tessar is not unlike the discussion of Tessar versus Planar, resp. Xenar versus Xenon/Xenotar, and Sonnar versus Planar/Xenon.
And the Triotar and other true triplets...? Stopped down they can (and do) produce good images.
With a hand held camera, standard consumer film and a bright day... the differences are (fill in the blanks)...