I read about a new 135mm lens developed by MS Optical:
http://www.japancamerahunter.com/shop/m ... 4-full-mc/
MS Optical lenses have a bit of a cult following, especially within the Leica circles. The design of the lens is intriguing! I know there are a few members here who utilize 135mm lenses as tube lenses for infinity corrected objectives. While this lens is probably much more than most want to spend on a tube lens, still a fun read!
Interesting new 135mm lens
Moderators: rjlittlefield, ChrisR, Chris S., Pau
Fascinating! I just bought the Sigma f1.8 135m lens, which some lens testing websites say is the new "sharpest production lens ever tested". The price is the same as the lens you cite, so the price of that custom lens seems quite reasonable. Wish I had known about it before buying the Sigma!
135mm is a great tube lens length, many of the objectives we use will cover an APS sensor with this tube lens.
135mm is a great tube lens length, many of the objectives we use will cover an APS sensor with this tube lens.
Lou,Lou Jost wrote:Fascinating! I just bought the Sigma f1.8 135m lens, which some lens testing websites say is the new "sharpest production lens ever tested". The price is the same as the lens you cite, so the price of that custom lens seems quite reasonable. Wish I had known about it before buying the Sigma!
135mm is a great tube lens length, many of the objectives we use will cover an APS sensor with this tube lens.
Do you plan on testing the Sigma 135 as a tube? Last Year I got the Rokinon 135, it's very sharp (equal to Zeiss) also but turned out not to be a good tube lens, later others found the same result. It's the sharpest lens I have, but the new Sigma is another level above. Plus your Sigma is AF the Rokinon is MF.
Best,
Mike
Yes, I bought it as a potential tube lens for microscope objectives and as a base on which to mount reversed lenses. It is a superb lens but may have more CA than the Zeiss 135 ZF2. I was torn between buying the Zeiss or the Sigma but decided on the Sigma for its high resolution.
I did remember the bad results of you and Beatsy with the Rokinon. But I never learned why exactly it was bad. Too much CA? Vignetting? I'm hoping the Sigma will be different. It uses two flourite-like glass elements so maybe....
I also bought a special Olympus 150mm f/2 as a tube lens and for lens coupling. Results so far show some slight purple fringing but very high resolution. Need to work more with that, but I've been too busy with work.
If the problem of the Rokinon is CA, it may still work well for black-and-white diatoms, etc using monochromatic green light, which would eliminate CA....I will try this with my Oly and Sigma.
I did remember the bad results of you and Beatsy with the Rokinon. But I never learned why exactly it was bad. Too much CA? Vignetting? I'm hoping the Sigma will be different. It uses two flourite-like glass elements so maybe....
I also bought a special Olympus 150mm f/2 as a tube lens and for lens coupling. Results so far show some slight purple fringing but very high resolution. Need to work more with that, but I've been too busy with work.
If the problem of the Rokinon is CA, it may still work well for black-and-white diatoms, etc using monochromatic green light, which would eliminate CA....I will try this with my Oly and Sigma.
I recall the Rokinon as a tube was not as sharp as I expected, Vivitar (Komine) you suggested was better. But boy was it sharp used as intended!! I did some tests using it as a base lens for other lens, results were Ok but not as good as I could get with Mitutoyo and various tube lenses.
Also tried it extended but results were just so so (think this is due to field curvature being optimized for sensor distance and becoming highly distorted when moved away from the optimum design distance).
Best,
Mike
Also tried it extended but results were just so so (think this is due to field curvature being optimized for sensor distance and becoming highly distorted when moved away from the optimum design distance).
Best,
Mike
I admit to being mystified about how to judge whether a particular lens is a good tube lens or coupled lens. But I suspect that a lens made from exotic low-dispersion glasses to control chromatic aberrations would be better than a lens made of regular glass, all else being equal.
The Raynoxes are crappy photographic lenses but great tube lenses. In fact they are halfway acceptable even when two are used together, one as a tube lens AND the other in front of it , with no other lens used! See
http://www.photomacrography.net/forum/v ... highlight=
One feature here is the lack of CA in the Raynox. I think that matters for a lens to work well as a tube lens, so it might be one thing to look for, though not the only thing. The Rokinon also has low CA so I would have expected it to be better, but it seems pretty unanimously bad.
Mike, where did you put the aperture when you used the Rokinon as part of a coupled-lens setup? Did you make a paper aperture and place it between the two lenses, or did you use the front lens' aperture? I think this may make a difference.
The Raynoxes are crappy photographic lenses but great tube lenses. In fact they are halfway acceptable even when two are used together, one as a tube lens AND the other in front of it , with no other lens used! See
http://www.photomacrography.net/forum/v ... highlight=
One feature here is the lack of CA in the Raynox. I think that matters for a lens to work well as a tube lens, so it might be one thing to look for, though not the only thing. The Rokinon also has low CA so I would have expected it to be better, but it seems pretty unanimously bad.
Mike, where did you put the aperture when you used the Rokinon as part of a coupled-lens setup? Did you make a paper aperture and place it between the two lenses, or did you use the front lens' aperture? I think this may make a difference.
May be way off but...
We often use something between about eff/12 and 24 when using a lens as a "tube" lens.
Down at f/22 marked, some lenses seem to be worse than just from diffraction, even if they're better than average wider open.
I remember years ago a lens of Tessar construction, 4 elements, beating something with many more, at small apertures. Maybe there's a reason why Zeiss used so few elements in their Luminars, in the days when macro meant small apertures?
First question then, is how well do the "unusually good" wide aperture lenses perform at small apertures?
I must go and buy them all to find out...
We often use something between about eff/12 and 24 when using a lens as a "tube" lens.
Down at f/22 marked, some lenses seem to be worse than just from diffraction, even if they're better than average wider open.
I remember years ago a lens of Tessar construction, 4 elements, beating something with many more, at small apertures. Maybe there's a reason why Zeiss used so few elements in their Luminars, in the days when macro meant small apertures?
First question then, is how well do the "unusually good" wide aperture lenses perform at small apertures?
I must go and buy them all to find out...
Chris R
I've just been poking around looking for comparisons.
The-digital-picture.com does show them to be as good or better than their smaller-aperture siblings. These days you don't get a 135mm f/3.5 to compare with though
.
Is there something else about the way we use camera lenses as "tube" lenses? We're only using a very small part of the front element, which is unusual, and more unusual for a wider aperture lens?
The-digital-picture.com does show them to be as good or better than their smaller-aperture siblings. These days you don't get a 135mm f/3.5 to compare with though
.Is there something else about the way we use camera lenses as "tube" lenses? We're only using a very small part of the front element, which is unusual, and more unusual for a wider aperture lens?
Chris R