compact 210mm bokeh

[raizans]

yes, another thread spawned by chris perez's six lens matchup!

http://www.hevanet.com/cperez/test/BigMash210.html

i'm interested in the bokeh of compact 210mm(-ish) lenses: the 210/6.1 xenar, 210/6.8 geronar, and 200/8 nikkor-m. another lens that he did not test is the 210/9 g-claron. then there are many vintage lenses.

the test only consisted of one photograph, which doesn't tell you much because bokeh varies from one picture to another. if you have extensive experience with any of these lenses, especially for taking portraits, how would you describe the behavior and quality of the bokeh?

[Ken Lee]

I made some of my own blur tests - but not with the lenses you mention. From what I can tell, Christopher's conclusions are right. For modern lenses of normal design*, focal length and aperture shape are the key determinants of blur rendition. Longer lenses, at wider apertures, give more blur. Circular diaphragms give circular blurry highlights.

Click here (http://www.kenleegallery.com/images/forum/150mmLensesSharpened.png) to see a test made with 3 different 150mm lenses at f/11. The lenses are Heliar, APO Nikor, and APO-Sironar-S. I made a similar test with longer lenses, 210 through 360. Let me know and I'll post that one too.

Note: The image is large, so your web browser might shrink it to fit the screen. You may have to click or right-click on the image to enlarge it.

This was not a resolution test to determine which of the lenses is sharpest. It wasn't a coverage test either. I just wanted to compare blur. These photos were made on 4x5, and the images were scanned at medium resolution. Levels Adjustments were applied in Photoshop to mitigate any differences in tonal scale, and the images were sharpened together.

* Portrait lenses are different. They are actually designed to give blur. As any fan of Jim Galli (http://tonopahpictures.0catch.com/) will tell you - and who here isn't ? - each design has its own signature. Heliars for example, give uncorrected aberrations when opened wide, but as the lens is stopped-down, the aberrations decline. By the time you get to f/11, the blur looks just like what you get from a Sironar, a Tessar, or any other non-portrait lens.

[Armin Seeholzer]

Ken I still she a tiny dif at the background, the Heliar is the softest in the out of fokus part! Very small but it is there!

[Ken Lee]

Ken I still she a tiny dif at the background, the Heliar is the softest in the out of fokus part! Very small but it is there!

You're right Armin. I see it, now that you have pointed it out. As you say, the difference is very slight. And I tried to choose my words carefully, calling focal length and aperture shape the "key" determinants of blur rendition.

Click here (http://www.kenleegallery.com/images/forum/210mmLensesSharpened.png) for the same test, with some 210mm and 240mm lenses: 210mm Heliar and Tessar, 240mm Fujinon A and APO Nikkor, all at f/11

My focus was slightly off with the Heliar. After reviewing these tests, I purchased a focusing loupe !

[rfesk]

The article published in Photo Techniques years ago about bokeh showed a photo taken with Leica 35/2 Sumicron 4th version (the so-called king of bokeh.) What stood out about that photo was the out of focus bright areas behind the object in focus still held their shape. It seems this is because the lens does not produce bright ring out-of-focus highlights like so many lenses do.

Doesn't seem that this has been explored in LF lenses as much as it should. I just purchased an older Symmar 150 with a 10 or so bladed shutter to see how the bokeh compares to other lenses.

[raizans]

the 35mm summicron pre-asph is a good example of the variability of bokeh. its reputation as "the king of bokeh" rests solely on its performance at medium apertures and medium focus distances. closeup and wide open, the bokeh is some of the harshest you'll ever see. mike johnston mentions this caveat in a footnote of his bokeh ratings pdf.

maybe my original question is too esoteric. i imagine that most people buy compact 210mm lenses for landscapes instead of portraits.

[David Karp]

I have a 210mm f/6.1 Caltar Pro, which is a nice, sharp, small and light version of the Schneider Xenar. I also have a 210 Caltar II-N, which is a Rodenstock APO-Sironar-N. The Bokeh is much nicer on the Caltar II-N, which of course is not compact.

Neither of them has a round aperture. The Caltar Pro is in a silver ring Copal with the blocky serrations. The Caltar II-N is in an all black Copal. It seems that the difference is based on the design of the lens.

[Ken Lee]

The Bokeh is much nicer on the Caltar II-N, which of course is not compact.

Can you support that wildly exaggerated claim :) with some sample images ?

[David Karp]

Hi Ken,

I can support my claim that the Caltar II-N is not compact! The Caltar Pro is on the left. The Caltar II-N is in the middle. (The one on the right is a Caltar II-E.)

[David Karp]

I can't directly support my claim regarding the Bokeh because I don't have any apples to apples comparisons. I think I might have an apples to oranges comparison for you. Just give me some time to dig it up.

[Ken Lee]

I can't directly support my claim regarding the Bokeh because I don't have any apples to apples comparisons. I think I might have an apples to oranges comparison for you. Just give me some time to dig it up.

I'm only half-serious, so even apples-to-oranges comparisons are more than welcome.

Or none at all, if it's inconvenient. This is a subjective area.

[David Karp]

Ken,

I knew you were kidding - that's why I compared the lens sizes instead of photos. :)

Scanning and digital printing are not my thing. So far, I just scan to proof. For that reason, I don't have a lot of scans to use as examples. So, that being said, here is what I have.

The first two photos are tests I did when I bought the Caltar Pro. One wide open at f/6.1, the other at f/22 (I think). The out of focus areas are nice on the wide open shot, but not so nice to my eye with the stopped down shot. These are both on 4x5 Arista 400 Professional (HP5+).

The third photo is a quick scan of a photo of my Dad and his grandkids. I used the 210 Caltar II-N on this one, at f/5.6. This photo was on 5x7 Arista.EduUltra 200 (Fomapan 200). I like the out of focus areas much better than those on the Caltar Pro. I know this is very subjective, and I can't really explain why. However, I notice that I have had this same feeling regarding other photos I have taken with the II-N.

Despite this, I really like the Caltar Pro. It is small and light, and very sharp. I don't see any need for a 200mm Nikkor M having this lens in my lineup. Most of the time, I go for sharpness across the image, to the extent possible.

[drew.saunders]

I looked through my shots with the 200 Nikkor-M to see if I had one that was fairly open and medium distance with oof background, and found just one:
http://www.flickr.com/photos/drew_saunders/4207400085/

Looks fine to me, but I just have that one lens in that focal length for LF.

Drew

[Ken Lee]

David -

I see what you mean.

Oops - I never tested at small f/stops. Oh well.

it's hard to beat those Sironars, for everything except size and weight. Here's (http://www.kenleegallery.com/images/forum/img102aaa.jpg) one made at roughly f/11 with 210 Macro Sironar-N.

[raizans]

The first two photos are tests I did when I bought the Caltar Pro. One wide open at f/6.1, the other at f/22 (I think). The out of focus areas are nice on the wide open shot, but not so nice to my eye with the stopped down shot.

i think the one at f/22 looks nice. it just isn't as blurry.

the foliage in the top right corner looks a little ni-sen at f/6.1, but i'm not sure if it's the photo or jpg artifacts.

the grass in the lower right corner of the caltar ii-n at f/5.6 shows bright rings, but it's not obtrusive because it's dark and at the bottom of the frame.

[raizans]

I looked through my shots with the 200 Nikkor-M to see if I had one that was fairly open and medium distance with oof background, and found just one:
http://www.flickr.com/photos/drew_saunders/4207400085/

Looks fine to me, but I just have that one lens in that focal length for LF.

Drew

some areas in the middle and lower right have hexagonal bright rings, and some of the curved branches in the lower half are ni-sen. since there's so much going on, it's not obtrusive in this photo, either.

[Jim Galli]

Thanks to Ken for such nice words, but after thinking on this for a bit I have to say that in my mind, compact and bokeh are mutually exclusive. Perhaps a 1940 - ish Kodak 203mm f7.7 pre-coatings would win the prize. But for me I would ever forfeit the grams and choose a Heliar if it's Bokeh I'm after. Cake and eat it too I suppose. I have a lovely old Bausch & Lomb 8 1/4" f4 Plasmat that the US Gov't paid way too much for in the 1950's that I've always meant to play with wide open and have not. It would hold a stack of papers securely in a hurricane though in it's #4 shutter.

[Ken Neely]

You're right Armin. I see it, now that you have pointed it out. As you say, the difference is very slight. And I tried to choose my words carefully, calling focal length and aperture shape the "key" determinants of blur rendition.

Click here (http://www.kenleegallery.com/images/forum/210mmLensesSharpened.png) for the same test, with some 210mm and 240mm lenses: 210mm Heliar and Tessar, 240mm Fujinon A and APO Nikkor, all at f/11

My focus was slightly off with the Heliar. After reviewing these tests, I purchased a focusing loupe !


Brother Ken, your candor made me smile broadly !

[drew.saunders]

some areas in the middle and lower right have hexagonal bright rings, and some of the curved branches in the lower half are ni-sen. since there's so much going on, it's not obtrusive in this photo, either.

Knowing enough Japanese to know that "ni" is 2, I'm guessing ni-sen is unwanted double lines or something like that?

[rdenney]

One thing I have seen is that lenses with a slight bit of undercorrected spherical aberration make a smoother rendition of out-of-focus details than do lenses that are fully corrected. The conventional wisdom is that this occurs behind the subject.

To me, an ideal lens for sharp portraiture occurs when stopping the lens down does not correct the spherical aberration so fast that the bokeh develops ugly artifacts such as bright edges or double lines. I have conducted tests of lenses for smaller format, but not for large format.

I think my favorite design is a classic Sonnar. But given that we don't really have that design available to us in large format, I would probably prefer a tessar design if my intention was to use a modern lens. When used wide open, these are not fully corrected, unless their maximum aperture is pretty limited. The fast ones tend to be pretty quick, too, and that helps a lot in the bokeh department. Sometimes, more blur helps more than smoother blur.

One example in this focal length is the Ilex Paragon 8-1/2" lens. It is a tessar design with an f/4.5 maximum aperture and the background blur is quite pleasing--moreso that I would expect from a well-corrected plasmat (like my otherwise stunning Sinaron/Sironar at 210mm). Another example, but not tested for this effect yet, is a Caltar Type Y 240mm f/6.8, which is also a tessar design.

The Ilex Paragon is mounted in an Ilex No. 4 shutter, so it is not small and light. But it is shorter front to back than plasmats of the same focal lenth, and the extra bulk is in diameter rather than length.

Rick "who prefers a faded edge rendering at wide apertures" Denney

[raizans]

yup, double lines.

stopping down unavoidably reduces spherical aberration. if the lens is overcorrected for spherical aberration, stopping down will therefore improve the bokeh behind the plane of focus. it won't be quite as blurry, and the aperture blades become a factor, but it's something to keep in mind.

a lens with undercorrected spherical aberration will have smooth bokeh behind the focal plane, either wide open or stopped down, especially if the aperture blades form a more perfect circle.

i wish lens designers would just say whether a lens is overcorrected or undercorrected for spherical aberration. that would make things a lot easier!