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William Mortensen
17-Mar-2006, 11:57
Just wondering; which lens designs would have the "swirliest" bouquet, oops, I mean bokeh? Petzvals seem to have the reputation for this effect, but what about rectilinears, rapid rectilinears, or even a simple meniscus lens?

paulr
17-Mar-2006, 12:11
now i'm curious. could you post a swirly example?

William Mortensen
17-Mar-2006, 12:16
"could you post a swirly example?"

Here's one of my favorites:

http://www.kerik.com/gum59.htm

Christopher Perez
17-Mar-2006, 12:19
Mark, I have witnessed this effect from tessars/xenars that don't cover the format. Most of the time you need to shoot wide, or nearly wide open.

Ernest Purdum
17-Mar-2006, 12:43
Ooh, tough question, partly because I am not sure what "swirliest" means.

Rectilinears, other than the "Rapid" variety, hardly exist. There were some wide angle rectilinears, etc., but I don't think any of these would be of interest in what I assume you are looking for. Rapid Rectilinears were, and are, rather sharp lenses until compared to modern anastigmatic types Their rather linmited .aperture (usually f8, don't get confused by one with a maximum opening marked "4", that's US4 which is only f8) means that a searcher for bokeh may find more depth of field than he would like.

Regarding a simple meniscus, the simplest, those with only one element, have strong chromatic aberration, which not only makes them weird on color film but interferes with focusing for black and white. Achromatic individual cells, like the back half of a convertible type, whether meniscus or a differing configuration, are often highly regarded for bokeh. The principal example is the Rodenstock Imagon, but there are others including one made by Kodak. Experimenters can try telescope objectives, but it is hard to find one with a large enough aperture and a modest focal length.

As you say, the Petzval, which is sharp in the center but goes soft towards the edges, has a reputzation and is a favorite of a number of users. The problem with these is that most were made for use on cameras both larger and more massive than are in common use today. Even if you can fit a "brass cannon" on your lensboard you may find it giving you front tilt that you don't want. Smaller ones do exist, however. Again for the experimental, very many projection lenses are Petzvals. These are nearly always cheap and finding a usable size one is common. The disadvantage, of course, is that they have no aperture control. Some people use them wide open, others have sawed a slot for homemade Waterhouse stops.

A type you did not mention is the anastigmat with a variable soft focus control. The Graf Variable, and some Cooke lenses, are examples. Quite a few of these were made in focal lengths about 9 1/2" and would quite likely give you the result you have in mind.

Getting good results from any of these, and particularly the variable anastigmats, requires a fair amount of playing around to get the desired results, but can be gratifying.

paulr
17-Mar-2006, 12:45
interesting. not sure what that is ... did you ask Kerik?

tribby
17-Mar-2006, 12:58
might try making a waterhouse with an ovoid or elliptical aperture.

i like yer photo in the link,

me

Steve Hamley
17-Mar-2006, 12:58
Paul,

Kerik posted how he did it on APUG, it was done with a 14x17" camera and a 18" Verito, which is short for the format.

http://www.apug.org/forums/showthread.php?t=15964&page=2&pp=10&highlight=bokeh

There's a good discussion at the link above.

Steve

Scott Fleming
17-Mar-2006, 12:59
Mark,

Hoo boy! That's swirley all right. Made me dizzy.

tribby
17-Mar-2006, 12:59
jinx...

din't read ernie's post to the end...

me

Jonathan Brewer
17-Mar-2006, 13:27
Where ya been Triblett?

Bob Salomon
17-Mar-2006, 13:56
The Imagon can do a similar effect given the right lighting and shooting at 5.8, especially without a disk.

tribby
17-Mar-2006, 14:35
i'm still here jonny...

just lurking is all...

me

Mark Sawyer
17-Mar-2006, 15:17
Chris- Hmmm... never associated that effect with a tessar, but then, I've never shot a barely-covering tessar *or* a wide open tessar.

Ernest- I have several dozen old lenses I've accumulated over several decades (before Jim Galli drove the prices up... grrrr!) These include petzvals, wide rectelinears, rapid rectilinears, aplanats, anastigmats, symetricals, rapid symmetricals, variable soft focus velostigmats, etc. I'm just wondering if any might be more prone to that "swirly" effect?

Steve- thanks for steering me to that thread on APUG! Don't know quite how i've always missed it in the past...

I've had an on-again-off-again theory that the swirly effect comes from using a long-barreled lens wide open, which allows for a more pointed/eliptical (lemon-shaped) aperture at the edges, getting very extreme just before losing illumination. The orientation of the ellipse follows the edge of the lens, so it would allow for a circular "swirl" going around the entire image. This is all due to the overlapping of the front and rear ends of the barrel openings, and would explain why Petzvals and Veritos are known for this effect, (both have relatively long barrels). And that led me to wonder whether the long-barreled rapid rectilinears would have the same effect wide open.

But the again, the short-barreled Imagon has some of that swirly effect too, so maybe the barrel-length theory doesn't hold up. I'm still not entirely sure of the optics behind it; I've read posts attributing it to coma, barrel distortion, various abberations, etc. Hmmmm...

Christopher Perez
17-Mar-2006, 16:20
Chris- Hmmm... never associated that effect with a tessar, but then, I've never shot a barely-covering tessar *or* a wide open tessar.

I hadn't either, until recently. That's when I found my 210mm Xenar f6.1 to be stunningly sharp wide open and had similar off-axis effects to Kerik's fine image. I'm looking forward to putting the Xenar on the 8x10 after following this discussion. :-)

darter
17-Mar-2006, 18:31
Are you sure that's bokeh in the sample photo? I always associated bokeh with areas outside of the sharp plane of focus, whereas what the image has is lens distortion within and outside the plane of focus. I get a similar effect with a verito which is only sharp in the center area, even when stopped down.

Philip_5765
17-Mar-2006, 19:33
Old projection lenses from magic lanterns.

David Richhart
17-Mar-2006, 20:00
Have you tried Vaseline smeared around the edge of a filter??? Perhaps it is not exactly what you are looking for, but it can create a similar effect.

Mark Woods
17-Mar-2006, 20:50
At the risk of sounding risque, Vaseline is opaque and does not give a very good result. IMHO. OTOH, KY jelly is optically clear and will give much better results in terms of making a swirling pattern around the subject. One of the R&D guys at Panavision told me about this, and it's true. I no longer carry Vaseline, but I do carry KY -- and it works! (Along with Fogal stockings, YSL stockings ....)

Cheers,
MW

John Berry ( Roadkill )
17-Mar-2006, 23:53
Phil, I would consider it bokeh. If it is as has been described, the quality of the out of focus part, anything out of the depth of field would fall into the bokeh zone. It would all be bokeh no matter what the cause of the particular effect is. I think the quantification of bokeh is strictly subjective. I think Kerics use of the particular bokeh characteristics in the image make it good bokeh. The same setup in architecture might not get you the check you were expecting.

Ole Tjugen
18-Mar-2006, 01:18
One of my "weirdest" lenses is a Xenar Typ D 15omm f:3.5. It goes seriously swirly outside the circle of good definition - like when I out it on a 5x7" camera. Just like the 50mm f:3.5 lens on my FED-2 35mm camera, in fact - just that that FED lens is a tessar type, unlike the Xenar Typ D...

As an aside, I agree with those earlier posters who don't want to call it bokeh. To me also that term implies soft out-of-focus areas within the circle of good definition, this swirl is what happens outside.

Neil Miller
18-Mar-2006, 03:45
It's a lovely picture, but I think that some of the "swirliness" is due to the background vegetation moving during a long exposure. I've seen similar examples from collodion negs where the movement in open-air shots due to breeze has added to the effect of shooting almost wide-open. Sometimes the effect is enormously distracting (not in the example quoted!) and, like someone above wrote, makes you feel dizzy.

Regards,
Neil.

jnantz
18-Mar-2006, 07:10
single cell lenses harvested off of folding cameras also give swirly effects, and they are pretty cheep.
some have a simple funnel like hole they screw into which acts as an fstop to reduce abberation and give a sharp image ( as sharp an image as a folder can give you )

...without the funnel-aperture these lenses give nice swirly effects. they also make beautiful portrait lenses ( color or black and white ).

Jason Greenberg Motamedi
18-Mar-2006, 08:04
In addition to what has been written about Petzvals, Veritos, and Type D Tessars, good swirlyness comes with an appropriate background. A solid color hides aberration while a "busy" background like Kerik's leaves shows distortion best. Find yourself an appropriate lens a bit shorter than recommended, and seek ye busy backgrounds...

moi
18-Mar-2006, 08:17
mark woods: . I no longer carry Vaseline, but I do carry KY -- and it works! (Along with Fogal stockings, YSL stockings

Aren't you glad the national parks don't have a Stop and Search directive? Park Ranger "Taking pictures? Sure! What's with the KY and stockings?"

Ole Tjugen
18-Mar-2006, 09:11
Just a quick comment: The Xenar Typ D is NOT a Tessar, but a triplet. That makes quite a bit of difference!

Frank Petronio
18-Mar-2006, 09:26
It can always be "helped along" by careful application of Photoshop's Radial Blur. Not that I am suggesting any of you would ever consider doing such a thing or you might be banned from APUG.

Like I was ;-)

Erik Gould
18-Mar-2006, 15:51
I have seen it with Petzvals, and a 3.5 Xenar that I used to own. Here is an example from that lens that shows some swirlyness: http://www.flickr.com/photos/egould/114330661/

and leica summarits are known for swirlies too, but that is of course for the miniature format. what summarits show is a different effect, i think, more of a bokeh thing, or whatever. the terms give me a headache.

Erik Gould
18-Mar-2006, 15:59
darn it, i can never get the links to work right:

http://www.flickr.com/photos/egould/114330661/