Petzval Picture Post Thread

[Eric James]

Although Joe Smigiel's nude is one of the more arresting photographs I have seen, I would not have thought that it exhibited "good" bokeh... Great Thread and great photography!

Joe Smigiel has defended this photo's OOF area earlier in the thread when I characterized the swirl as "mildly distracting". I've reconsidered my comments with the help of his response (I can do this, can't I?). I think that these tiny jpegs don't do these photos justice; and I think that my focused evaluation of these images' bokeh has over emphasized the OOF qualities. It's now clear to me that the folks here shooting with these lenses have employed their OOF rendition wittingly with great effect.

I'll wait to see these or similar images in print before I chisel out my opinion in granite

I love the swirl too! Great shots and thank you for sharing them! BTW, is the swirl effect which was produced in your photograph of the girl, as compared to the still life, due to the distance from the camera to the focus point or did you adjust the rear cell? Jon

John, without any evidence to the contrary, I believe you're correct concerning the importance of distance between the focus plane and out-of-focus swirl. I haven't seen the so-called swirly bokeh (SB) in any photos that don't have OOF areas a few meters or more from the focused subject.

I'd also like to suggest that the SB often shows up when the OOF area is composed of trees or tree branches. This is true of every photo with SB I've run across. Some characteristic of tree branches lend themselves to SB - not just in this optical formula, but with other lenses that provide SB.

I still don't understand the source of the swirl. For example, why does it appear as a swirl, rather than being more concentric?

Monty - your photo of the girl with the wagon is beautiful!

As an after thought, notice the similarities in Joe's and Monty's portraits: the subject is centered thus capitalizing on the artist's expected OOF rendition; the OOF subject is composed largely of trees positioned multiple meters from the focused subject; the SB leads the eye to focus on some dramatic portion of the image (the nipple/face or the girl's curly hair).

[Struan Gray]

John, without any evidence to the contrary, I believe you're correct concerning the importance of distance between the focus plane and out-of-focus swirl. I haven't seen the so-called swirly bokeh (SB) in any photos that don't have OOF areas a few meters or more from the focused subject.

I'd also like to suggest that the SB often shows up when the OOF area is composed of trees or tree branches. This is true of every photo with SB I've run across. Some characteristic of tree branches lend themselves to SB - not just in this optical formula, but with other lenses that provide SB.

Final print size has a lot of influence on just how distracting the swirl becomes. As a print gets larger the overall formal composition becomes less dominant unless you step right back. In this case the swirl distracts less and less - or at least, the photo looks less and less like it has been taken down a tunnel.

Narrowing of the iris off-axis is one source of swirl, but not the only one. Asymmetric aberrations like coma and astigmatism will also make fine detail whirl about in orbit. Some of the most swirly photos I have taken were with a cheap zoom lens on 35mm: on the macro setting close up pictures of flowers in grass ended up quite dizzy, mostly because of coma.

High-contrast fine detail will show the swirl most effectively. Tree branches against a lighter sky work well, but other things will do the job. For a very different sort of subject matter see this picture:

http://www.shorpy.com/node/480?size=_original

Effects due to the cat's-eye narrowing of the iris will be very distance-dependent, but aberrations from wide-aperture use on a poorly-corrected lens can be less so. I suspect this photo's swirl resulted from trying to keep the exposure as short as possible. Alexander Gardner presumably had access to 'better' lenses.

[Ole Tjugen]

...

http://www.shorpy.com/node/480?size=_original

Effects due to the cat's-eye narrowing of the iris will be very distance-dependent, but aberrations from wide-aperture use on a poorly-corrected lens can be less so. I suspect this photo's swirl resulted from trying to keep the exposure as short as possible. Alexander Gardner presumably had access to 'better' lenses.

I'll hazard a guess that that picture was taken with a Periskop-type lens. These lenses (together with Aplanats/RR's, which weren't invented until the following year) have a strong astigmatism, where the tangential focus returns to the baseline at about 30° off center while sagittal focus shoots off into the unknown.

Meniscii, landscape lenses and Petzvals don't return to zero at any point so the "swirl" wouldn't have been as painfully sharp.

[Marko Trebusak]

OK, here is my contribution. Taken with Petzval type lens from unknown Magic lantern. Roughly 6" long wide open (no other options anyway) at f4.5 and 30 sec on 4x5 Delta 100, developed in Pyrocat HD.

Marko

[Jim Galli]

Here's one that doesn't "swirl" although it couldn't get much wilder.

obviously haunted house

Done hand held with a Speed Graphic and a little 4" Wollensak Projection petzval of about f3 aperture. Film was some ancient tri-X that had come in some holders with a camera outfit I bought to get the lenses. This is one of those times you wish you had been a little more serious about the quality of the capture. Do over's never seem to work.

[Eric James]

Thanks for the explaination and other comments Struan. I've been trying to get the shorpy link to open since soon after you posted your response, but my connection is having a bad day. I might have to go to work on my day off, thanks to you

[Struan Gray]

Thanks for the explaination and other comments Struan. I've been trying to get the shorpy link to open since soon after you posted your response, but my connection is having a bad day. I might have to go to work on my day off, thanks to you

Shorpy is worth a browse when they get back up, but they get their photos from the Library of Congress. The photo I referred to is here:

http://memory.loc.gov/service/pnp/cwpb/04200/04200v.jpg

[Robb_Scharetg]

Jim et. al.

A very interesting thread to say the least. Thought I'd throw a few out there, although they're not Petzval lenses, however they do have an interesting 'visual signature' none the less.

1st shot (Bar shot) is with a Reitzschel 135/1.9 (L) shot at 1.9, (R) @ 2.8., shot on a Speed Graphic-Polaroid film. Quite a difference between 1.9 & 2.8 eh?

2nd shot done with a Grun Anistigmatic (9" I think, @ 4.5-W.O.) on NC 160/Speed-Graflex Type D. Wonderful lens, great look, hard to find.

3rd shot-150/2.8 Xenotar-W.O., on a 3.25x4.25 Super D, VC 160. Great old standby lens, works for everything.

4th shot-©David Burnett (got to put that in there-he shot it), done on a Speed Graphic, 165/1.8 Ernostar, shot wide open. Very interesting signature.

I'll load more in a bit shot with other glass. Comments?

[Jason Greenberg Motamedi]

Robb,

I have been facinated by Ernostars (with or without David Burnett) for some time, any chance you have any other images made with it? I would love to see them.

Thank you.

[Robb_Scharetg]

Hi Jason

I may have a few more of my kids that David shot, I'll need to look around my HD to find them-it'll be a bit before I can post.