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Coma


Guest d.sge

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I'm with you, Wizard.

 

The presence of coma wide open leads me to believe that such an offending lens (think the Voigtlander Noktons) was created by a manufacturer thinking that lens would be used on an APS-C camera. Why will people spend money on that? Show yourselves. I'd like to feel less like an ass after seeing examples of when those spirally corners benefit a photograph. I really don't get it.

 

Hmmm - so the 35mm Summicron/Summilux pre-ASPHs, which show coma by the boatload - were somehow intended to be used on APS-C sensors? Which would not exist until 20 or 40 years after they were designed?

 

Leitz/Leica must have had one heck of a psychic working for them in 1961 and 1979, to predict the existence of APS sensors in the 21st century. ;)

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Guest d.sge

Hmmm - so the 35mm Summicron/Summilux pre-ASPHs, which show coma by the boatload - were somehow intended to be used on APS-C sensors? Which would not exist until 20 or 40 years after they were designed?

 

Leitz/Leica must have had one heck of a psychic working for them in 1961 and 1979, to predict the existence of APS sensors in the 21st century. ;)

It's not the past anymore. Welcome to the future. Incrementally Leica has no doubt sought to improve optical deficiencies in their lenses, apparently while other manufactures are content to rest on the laurels of Leica's heritage. Thank goodness for Leica (and Karbe) looking ahead.

 

I still haven't seen an example of coma benefiting a composition here. Surely there are some. Got a link to any? Talk is cheap.

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Guest d.sge

I don't understand sorry. Would you mind to elaborate?

I couldn't figure out how to upload an image of mine to this thread for illustrative purposes, so here are a couple or swirly cornered examples via flickr:

 

...flickr.com/photos/phillipabbott/5054845203/

...flickr.com/photos/alwang/16825087385/

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Modern coma. Zeiss Loxia 35/2 at f/2:

http://tinyurl.com/hb3cshl

 

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Simply register for free here – We are always happy to welcome new members!

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Guest d.sge

This photo of Albert Camus does not show coma, but is interesting given that is by Cartier-Bresson.

One of my long favorite lenses is the Summilux 35mm for its wide-open behavior when necessary.

Of course, these are from the past.

That Summilux photograph reminds me of the sort of thing ZM Sonnar detractors complain about, not that that photograph is anything to complain about. But I don't see any coma there either.

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It's not the past anymore. Welcome to the future. Incrementally Leica has no doubt sought to improve optical deficiencies in their lenses, apparently while other manufactures are content to rest on the laurels of Leica's heritage. Thank goodness for Leica (and Karbe) looking ahead.

 

I still haven't seen an example of coma benefiting a composition here. Surely there are some. Got a link to any? Talk is cheap.

Why does it have to benefit composition? It's a side effect of other choices. See the Loxia example above: it doesn't really detract, and it rather have a bit of coma than have the lens be twice the size and twice the cost.

 

Re: Karbe, thank goodness the older lenses still work, so we all have options to choose what suits us.

 

Re: looking forward: I can pretty safely say that all lens designers and manufacturers strive to continuously provide highly corrected lenses. Take a look at the latest Sigma offerings, or the Zeiss Otus, or even the 1.8 Nikon primes. Leica just have to work with viewfinder blockage which adds an additional level of difficulty. When that is removed, their lenses ballon to SL sizes just like every other manufacturer.

 

I sense that you consumed a lot of Leica kool aid.

 

Michael

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Guest d.sge
 

Why does it have to benefit composition? 

 

Why else would you want it there unless it does? You're a photographer.

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I couldn't figure out how to upload an image of mine to this thread for illustrative purposes, so here are a couple or swirly cornered examples via flickr:

...flickr.com/photos/phillipabbott/5054845203/

...flickr.com/photos/alwang/16825087385/

 

Difficult to be sure w/o knowing the exif data of your pics but it seems that you chose a wide aperture in both cases. Which could explain that the main subject matter is sharp while foregrounds and backgrounds are softer.If you want to avoid this softness, you may wish to try a smaller aperture, a wider lens and/or a smaller sensor in order to get a wider DoF.

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Why else would you want it there unless it does? You're a photographer.

Sorry, I might not have been clear.

 

How does more and more sharpness benefit composition? I know that you might be able to see more sharpness, and you may want more. It might help your final image (or not) by allowing you to print larger or show more detail, but that is not composition.

 

How about flare? Some artists use flare compositionally very well, so reducing flare is not always good, yet that is what most lens designers strive for it appears.

 

Maybe we are different types of photographers?

 

Cheers,

Michael

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Don't tell me that it is a lens from 1935 ;). The "new" ZM 35/1.4 doesn't look much better from this viewpoint. I have no experience with either lenses though and i've lived well with the coma of my Summilux 35/1.4 pre-asph anyway.

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Don't tell me that it is a lens from 1935 ;). The "new" ZM 35/1.4 doesn't look much better from this viewpoint. I have no experience with either lenses though and i've lived well with the coma of my Summilux 35/1.4 pre-asph anyway.

 

 

Hahah, it is a modern lens derived from an old, successful design.

I own the ZM 35/2 and find it a very good lens.

The ZM 35/1.4 is a Distagon design (i.e. retrofocus), but quite modern and suppoedly much better. Never tried it, though.

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Guest d.sge

Sorry, I might not have been clear.

 

How does more and more sharpness benefit composition? I know that you might be able to see more sharpness, and you may want more. It might help your final image (or not) by allowing you to print larger or show more detail, but that is not composition.

 

How about flare? Some artists use flare compositionally very well, so reducing flare is not always good, yet that is what most lens designers strive for it appears.

 

Maybe we are different types of photographers?

 

Cheers,

Michael

 

I think you were clear, Michael. I'm not speaking of sharpness, or any particular "character" that a lens will exhibit other than coma. If a photograph is enhanced by swirly corners, I can't think of any remarkable (not to say there aren't, hence my initial inquiry. I assume portraiture might be one area where heavy coma could aid in a certain mood being communicated). Having ample experience with various Nokton Classics, I've come to learn their compromises are often in the corners (lot's of vignetting, which is easy to correct if desired, and tons of coma, which isn't). I was surprised to find the 35/2.0 ZM Biogon opting for that same sort of comprise. Put's was indeed enlightening when he stated the Biogon design was a stretch. Needing a night time 35mm equivalent to  my 35/2.8 Biogon (tons of vignetting, and a beautifully rendering lens, I came to this thread wondering where the 35/2.0 and faster lens alternatives to the FLE and ASPH Summicron might be hiding. Surely lot's of alternatives covering ever walk of life must exist, just like the U.S. primaries...

 

#There'sstillachancetofeeltheBern.

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Are you talking about coma or swirly corners?

 

Coma is when a point of light is no longer a point, usually maifests as a bat wing shape. And usually on wide angles in the corners as in the Loxia pic above.

Swirly corners are a different thing entirely showing in the out of focus background.

 

Either way, as you know, life is a compromise. Make your choice and deal with it accordingly.

 

Michael

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