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?
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?
now i'm curious. could you post a swirly example?
"could you post a swirly example?"
Here's one of my favorites:
http://www.kerik.com/gum59.htm
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.
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.
interesting. not sure what that is ... did you ask Kerik?
might try making a waterhouse with an ovoid or elliptical aperture.
i like yer photo in the link,
me
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
Mark,
Hoo boy! That's swirley all right. Made me dizzy.
jinx...
din't read ernie's post to the end...
me
Posting Permissions
Reply With Quote
Bookmarks