That was a great synopsis, Ole.
I'm interested in the aesthetic qualities of different designs.
A simple meniscus lens, for instance, won't have a very wide circle of good definition, so they'll look sharp in the center with the particular kind of out-of-focus qualities at the edges that can be seen in some fairly early 19th-century portraits.
Heliars from wide open to about f:8 produce a very distinctive, almost three-dimensional effect where the in-focus subject really stands out from a smooth out-of-focus background. Some Planar types, like the Voigtlander Ultron, from the 1950s have this quality as well, but not all of them (for instance, I tried a 1940s Zeiss Planar for Contax that was dreadful as far as out-of-focus rendering goes--probably overcorrected).
Dagors, because they have 6 elements for the designer to play with, are fairly well corrected (some uncorrected spherical aberration results in apparent focus shift wide open) and have a wide coverage circle, but because they are in two groups, they are fairly contrasty, even in uncoated versions. The Planar exists in 5, 6, 7, and more element versions, and is theoretically superior to the Dagor, but because it has so many glass-air surfaces (thus inherently low contrast), it didn't really come into its own until the introduction of lens coatings. Now it is one of the most common designs. Most 50mm lenses for 35mm cameras are variants of the century-old Planar.
The Goertz Celor is another design that was considerably improved with the advent of lens coatings. Originally it was a budget version of the Dagor with two elements removed and replaced by air-spaces acting as elements. The Fujinon C series is an updated, coated version of the Celor, and has been seen as a real success.
</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (David Hall @ Mar 31 2003, 11:39 PM)</td></tr><tr><td id='QUOTE'>Drilling even deeper into my naivete...
Tunnel View with half a dozen other Ansel Alikes, and you know how many elements and in what groups my lenses are made up of, what is it that you can tell me about my lenses or how they will see?
Likely nothing you don't know from using them. OTOH lets say you walk into a little shop one morning. It's a junk shop but in one corner is a pile of old lenses. Having a vague idea of what each design can do makes it easier to find a deal. Maybe you're looking for a lens to cover an ULF camera. Now if you aren't looking to buy a lens I'm not sure any of the trivia really matters. The lenses you own are best tested on a camera with film. Two lenses from the same manufacturer made the same year can vary.
Once again this forum proves to be one of the most informative resources I can think of for photography. Thank you for all the information.
Other than Ole, is there a resource that makes it easy to understand such things? It turns out I WAS in a store yesterday, Samy's in Hollyweird, looking at old lenses in old shutters and not really having much of an idea of what I was looking at. Since I have only modern lenses (the oldest I have is a Schneider with the chrome outer ring and chrome ringed shutter) I couldn't tell which small, old lenses would cover a 5x7 or an 8x10. I kind of assumed that if a lens is 240+ mm, it would probably cover 8x10, but I really have no idea.
Thanks for whatever you can offer.
Somebody I'm sure can suggest a book. I'd suggest just surfing over to google and searching the rec.photo.equipment.large-format archives. Plenty of info is buried in there. A 240mm lens would need to be a wide angle design to cover 8x10.
</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (OleTj @ Mar 31 2003, 10:12 PM)</td></tr><tr><td id='QUOTE'>Then came the "anastigmat": Two lens elements, one positive, one negative, cemented (usually) together.
The "double anastigmat" is, with a few variations, the basis for all modern lenses. This consists of two anastigmats with a bit of space (and an aperture) between. The convex sides of both groups face out (from the aperture).
The Tessar is a double anastigmat with the rear anastigmat uncemented - 4 elements in 3 groups.
You really set the brain to working on this one, Ole.
I had workd for many moons in a company whose main product was "advanced optical systems", and that message brought back many memories.
I cracked the books, manly to refresh my memory - and ...
The *first* "camera" lenses - actually in use on the "camera obscura", were simple single-element meniscus lenses ... later to be called "landscape" design. Later, Chevalier designed the "Achromatic Landscape", by cementing another element to it, in 1821 - named for the fact that it corrected a lot of the chromatic abberations of the original "landscape" design.
The "anastigmat" design (remember that astigmatism - where lines that are supposed to be straight - aren't, therefore; "a"(n)+"astigmatism") does not appear to be a separate design in itself: the first reference I have to it is in the description of the "Protar" and "Double Protar" - designed in 1891 and 1895 by Rudolph, and the "Dagor" by Van Hoegh in 1892. These were all made possible by advancements in glasses - mainly by Abbe and Schott.
A "double achromat - with the rear two elements air spaced", would described the "Petzval" portrait lens of 1841. The Tessar is an assymetrical four-element design, with only the rear two elements cemented together - designed by Rudolph and Wandersleb, in 1902.
How does one tell how the photograph will look when taken with the various lenses? I really do not have a clue. I will go along with Aggies description - the "Little Genie" idea. For all intents and purposes, this WORKS.
I've heard long deep, incomprehensible discussions; "The *fool* took this photograph with a Tessar lens ... everyone KNOWS he should have used a Dagor...."
Uh-huh. Right. I'll file those conversations with all the others in the "Everyone Knows" file. Someday ... I'd love to set up a really valid experiment - taking various photographs with equivalent lenses - although that would not be an easy task. Other than the obvious differences due to focal length, I wonder how many photographers would be able to distiinguish the difference between the Zeiss Planar and the Sonnar - or Distagon - from prints produced with the Hasselblad?
Would be interesting ... but until I become one of the "idle rich" - I have other things to do.
My point, through all this, is that I don't think the modern lens design matters much.
The standard reference for the classic lenses is Kingslake, which is hard to find and expensive. I've looked at it at the library, but don't own my own copy. There is another book by Neblette that's not too bad, but has some obvious errors.
What can be done with this knowledge is that you can start to look for and select lenses based on the qualities you like. I've discovered that I like Heliars for portraits, so I've made a point of looking for heliar-type lenses for different formats. They're not all so great, and the effect can vary, but you can try things and sell them if you don't like them, usually without any loss. My favorite portrait lens for 35mm is a 100mm/3.5 Kodak Ektar, which is a coated heliar type lens, which I cannibalized from a defunct Kodak Medalist camera to use on my Canon F-1N. Lanthars and Apo-Lanthars are heliar-types. Leitz Hektors are generally Heliars, but are considered less desirable among Leicaphiles. I also discovered that the Canon FD 100/2.8 Macro is a heliar, but I haven't tried that one.
It also does help you sort out the odd lenses and figure out what they might be able to do without having to test each one. A 240mm artar-type lens probably won't cover 8x10" at infinity, but a dagor-type probably will cover stopped down and should have decent contrast, and say you find some obscure 16" double anastigmat made around 1910 by an English or French manufacturer in good condition at a nice price, and you need something that covers 12x20"--it would be a good bet that it would work, and you would be very hard pressed to find a Goerz Dagor of that focal length.
Or when someone shows you a 1912 Zeiss Planar, you'll know that despite the brand name and the big maximum aperture, this is an uncoated lens with lots of glass-air surfaces, so don't expect it to have good contrast.
Keep the guidance coming, it's great. But I am amazed tat you guys know this stuff!
Most of my information is from old German books - 1900 to 1910 or thereabouts. I came across one (Photographisches Hifsbuch für ernste Arbeit; Hans Schmidt, Berlin 1910) in a lokal bookstore, and realised there was a lot of information still valid in it.
Any errors in my "synopsis" are due to the effect of translating from one foreign language (German) into another (English) through a leaky memory (Norwegian).
As to "bokeh", I've just started a mini-test on this. I realised I had a 120mm Angulon, 135mm Planar, 150mm Apo-Lanthar, 150mm Symmar, and a 150mm Heliar - all "vintage" lenses. With four different lenses with such close focal lengths, I just have to test it...
Developed the first test today, the Heliar. Did this one alone since it's on a Voightländer 9x12cm plate camera from 1934, and I didn't want to remove the lens.
Rest to follow when I get time - and decent weather.
A couple more things. If you're looking to save a few $$$ then look for lens that don't come with the big name. B&L in the US made Zeiss lenses under license. Should be the same thing but you'll hopefully end up paying less.
Old fast lenses tended to be special purpose lenses. Either for press use or something else that needed the speed. I think the big leap I had to make when thinking about LF lenses was the 35mm view that faster is better. If you use a lens at F/16-F/32 all the time does it really matter how fast it is wide open? Or even how good wide open? Which is why I ended up just pushing things all the way to using barrel lenses.