Not that I know from experience, but isn't there an entire smorgasboard of personal lubricants available? Not to mention the natural alternatives, mucus, spit, and nose oil?
I am not sure, but it seems like the new Cooke would do better with rendering color than most of the older lenses that work so well for B&W. But I am not a lens geek -- I just know that looking at a digital capture at 100% really exposes a lenses flaws so much more than traditional. And what Jack needs for the scan back is an APO that still has that old and beautiful bokeh.
Over the years I have tried all manor of techniques to try and replicate the singular look of certain old lenses. These involved virtually every available filter from Softars, to diffusion to soft contrast. I tried applying Vaseline, clear nail polish, hair spray, various inks and compounds to UV filters. I sampled various thicknesses and colors of cellophane, gel filter material, white netting, black netting flesh-colored netting, all without and with holes of varying sizes in them.
The end result was that the Softar was the best effect of all of them IMO. BUT it still does NOT match the look from a classic lens. Moreover, as soon as I became proficient with Photoshop, I could quite easily replicate the Softar effect. All modesty aside, I am pretty darn good with Photoshop and cannot accurately replicate the look I see in some older LF lenses.
I even have tried removing cells and changing cell spacing in a variety of lens all to no avail. The Rodenstock Imagon does have a singular look, though it is somewhat harsh relative to the Cooke. Yet both of these lenses produce a generally softer effect than the "mojo" I am referring to above, though the Cooke stopped down to f16 and further is on the money. I think the best word so far has been "Yumminess" -- sharp yet buttery smooth -- that is what I'm looking for
As far as the shape of the aperture, that may in fact have a lot to do with it, but the Cooke and the Rodagon are in the same shutter and they generate very different looks.
As far as the shape of the aperture, that may in fact have a lot to do with it, but the Cooke and the Rodagon are in the same shutter and they generate very different looks.
I believe this is attributable to lens design. While both lenses (Cooke and Rodenstock) are deliberately designed for "softness" at certain apertures, I think they attempt to achieve it in different ways.
For lenses that are designed to be sharp, aperture appears to provide one of the most influential controls over rendition of out of focus areas. This seems to hold true independent of optical design.
For lenses designed to be soft, it appears to me that optical design overrides, to a larger extent, aperture shape at wide apertures. But even here, there are examples on-web that show the out of focus effects of the shape of the pasta strainer disks that the Imagon uses.
... look online and compare the curves of that Schneider Xenar of yours (sharp, yes, but still a dated design) and compare it to the same focal length Apo Symmar. You'll see that in many situations, the Xenar is just as good. But that in many it isn't...
Tessars are patent date 1902. Plasmats are patent date 1925 (from http://www.panix.com/~zone/photo/czlens.htm). To me, this means both designs are quite old. This leaves room for improvements in the implementations of both designs.
I am well aware of the MTF charts for tessars and plasmats. In addition, I consider two things:
1) Will I use the vast coverage of a 210mm plasmat on 4x5 (my current format of choice)? My answer is no. The tessar coverage is more than enough for the kinds of work that I do. But if I worked in 5x7 and needed rise/fall image controls, a plasmat would be a better choice.
2) In the real world, many of the design effects we are talking about here are masked by other factors. Film, processing, lighting, and focusing accuracy of a camera system have large influences on the outcome of an image.
Years back when I lived in LA and worked as a B&W print tech on Sunset Blvd (as part of Samy's Camera), I had the opportunity to study St. Ansel's early photograph of Half Dome. We all know the image. It's the one he took with a red filter. Anyone recall the lens he used? Anyone taken a critical look at the edges of St. Ansel's prints of this image? Yes, you see some "pulling" due to being at the edge of the field for the lens he used. But the resolution and contrast is incredible.
So it comes down to: Are we as photographers capable of utilizing our equipment to the fullest design extent possible? Only you can decide.
In the mean time, I'm off to play some more with a few Heliars, old Symmar Convertibles, and modern tessars. The old stuff may give a few hints at that illusive "mojo"... :-)
One word answer....Verito.....Three word question.....What is photoshop?....lol....Mojo? Wasn't he a man that thought he was a woman?... oh wait, that was JoJo.
"Tessars are patent date 1902. Plasmats are patent date 1925"
Christopher, are you suggesting the Apo Symmar is a 1925 design? These are the dates of the first designs that used the Tessar and Plasmat topology. They are not the dates of the current designs implemented in these lenses. As far as I know the Xenar hasn't changed much since 1919 (if it has, it probably hasn't changed in the last several decades). But the current Apo Symmar is a redesign from just a couple of years ago, and the latest in a process of evolution that's been going on every decade or so for a long time. It's a 21st century design that's the descendant of a 1925 design.
If you don't think you can see the difference between a Xenar and an Apo Symmar in the real world, try taking a picture of a building, with plenty of front rise, and then compare the upper corners. The difference won't likely be subtle--assuming the Xenar has the coverage you need at all.
Christopher, are you suggesting the Apo Symmar is a 1925 design? These are the dates of the first designs that used the Tessar and Plasmat topology. They are not the dates of the current designs implemented in these lenses. As far as I know the Xenar hasn't changed much since 1919 (if it has, it probably hasn't changed in the last several decades). But the current Apo Symmar is a redesign from just a couple of years ago, and the latest in a process of evolution that's been going on every decade or so for a long time.
I'm arguing this the other way around. Plasmats have been improved over time. So too have Tessars. What I have also tried to point out is that an old lens used within it's coverage area will be a very very usable optic and that there are few reasons to avoid them.
If you don't think you can see the difference between a Xenar and an Apo Symmar in the real world, try taking a picture of a building, with plenty of front rise, and then compare the upper corners. The difference won't likely be subtle--assuming the Xenar has the coverage you need at all.
Wherein lay the nub of your argument vs mine. I have looked at how tessars and plasmats fall off toward the edges of their fields of coverage. They are similar. Of course a tessar has less coverage and it can't be used with as much rise as a plasmat can under identical conditions. There's really no arguing this and I believe we are in agreement.
You need rise that gets your 210mm to the limits of what a plasmat gives. I don't, because it's a heck of a LONG ways up there to reach those limits. In shorter focal lengths, I either accept the limits of what a lens will cover, or I buy a wider coverage optic.
I'm also a bit skeptical of the aperture blades as the only factor in determining bokeh (or character, or mojo ...) i've just seen too many well-researched and well-illustrated examples of the role of aberrations.
I have been talking with a lens designer over dinner. It has been, how shall I say, illuminating.
Aberrations are curious things. In LF lenses we take certain properties for granted. Many of the more popular designs are easy to build and control aberrations fairly well (all things considered). Smaller format lenses (which much of the "bokeh" whoohaa has revolved around and most of the on-line investigations have been devoted to) make certain tradeoffs that make aberration control more difficult. Hence you see more variability that leads to these kinds of discussions.
Within LF work, I believe my comments hold true. Aperture shape controls the rendering of out of focus areas. The exceptions being lenses specifically designed to retain a certain amount of controlled aberration. Of course there will be lenses from any manufacturer that are of poor construction or alignment, and these can pick up undesirable qualities on their way to market.
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