How different are Tessars from different companies?

[Drew Wiley]

Enlarged just a bit. But it's a different topic than vintage tessars anyway, which I suspect are coveted more for a certain image look rather than portability or sheer sharpness. The relatively late single-coated Fuji L series was prized by portrait photographers because it was less harsh than certain other options. I use the 300M most frequently as a long lens for 6x9 roll film backs, where it's sharper than even my 300 EDIF P67 lens, which is pretty much the Mercedes Benz of MF telephotos, as good as they get. But it's more at home for 4x5, and usable on 8x10 if movements are distinctly conservative. The 200M is another superb 4x5 lens. I also have a 105/3.5 M, another jewel, but suitable only up to 6x9 format. Having a nearly full selection of Fuji A plasmats also, along with Fuji C dialytes, plus some regular plasmats, I have a good basis for apples to apples comparison. Each lens has its particular reason, though I doubt I'd
have any real issue if I had to thin out the set to a third the number. LF lenses got so darn good while they were still being made, that it's hard to go wrong with any of em, though as I have gotten older the lighter wt ones appeal to me a lot more.

[Bob Salomon]

Sexton's work tends to be 4x5 and enlarged, so there's a whole 'nother lens involved. Just to muddy the waters...

Except he also uses a 57 Super Technika V.

[Drew Wiley]

Well, at the time he was quite fond of the 200M, which has limited coverage on 5X7. The 300M would be excellent for that format, and I recall he liked to travel with that lens too. I've only chatted with him in person a few times, and that was long ago. Doesn't matter; I have my own valid reasons for specific lens preferences, and neither St Ansel nor his immediate cowboy hat disciples have much sway with me. For one thing, I started out as a color printer.

[Mark Sawyer]

Except he also uses a 57 Super Technika V.

"For 99.9% of my work I use a 4x5 view camera." John Sexton

http://www.photovisionmagazine.com/articles/sexton.html

[Jim Galli]

... and I’d suggest that a “reverse Tessar” - Radar - is in the same performance camp as a regular Tessar.

And here I thought that a reverse Tessar was a Petzval ;~'))

[erian]

I learned a lot. Thank you all.

[reddesert]

Interesting. Does it have anything to do with having the more open aperture of 6.3s? But then how would that explain the f9 450 Nikkor M which covers 12x20 with coverage to spare?

Dan answered this question but I will offer a slightly different phrasing. Lens design involves optimizing some parameters that the designer can control to satisfy a set of constraints. Parameters include glass types, element thicknesses, curvatures, and spacings, for example. When the Tessar was first patented, this optimization was done analytically and by iteratively trying solutions. Kingslake walks through the process for an f/4.5 Tessar in the book "Lens Design Fundamentals." Since the 1960s of course these optimizations can be programmed on computers.

The aperture, desired image quality (minimizing aberrations), and angle of coverage are all constraints. Generally, if one relaxes a constraint, it should be possible to do better on some of the others. Faster systems certainly do have more serious aberrations. Making a Tessar-type design slower aperture appears to allow the designer to increase its coverage.

I don't know enough lens design to understand exactly how. However, in Kingslake's walkthrough of the f/4.5 Tessar, for example, at some point he calculates the off-axis aberrations for 17 degree oblique rays (ie a 34 degree angle of view) and has to introduce some vignetting in order to cut off the oblique rays passing through the outermost edge of the rear group, to keep coma and other aberrations within reasonable limits. Presumably, with a slower lens, he could have allowed more oblique rays (greater field of view) before aberrations became too large.

[Pere Casals]

Making a Tessar-type design slower aperture appears to allow the designer to increase its coverage.

Not only for tessars!!

[Ron (Netherlands)]

My experience is that my (older) 6.3 Tessars provide more crisp images than the later 4.5 Tessars.

[BrianShaw]

And here I thought that a reverse Tessar was a Petzval ;~'))

It’s possible I got the “design” name wrong. I intended to be talking about Tessar derivatives, like the Gundlach Radar that I enjoy using as much as any other Tessar design lens.