Difference between Xenotar 135/3.5 and Zeiss Planar

[Arne Croell]

As has been pointed out by several people, there was the 250mm f/5.6 Sonnar for Linhof. They also made the equivalent Sonnar for the Baby Technika, a 180mm f/4.8. The latter covers 140mm wide open, so it is quite close to 4x5 coverage and stopped down does cover 4x5. Zeiss also tried a few more Sonnar prototypes for LF, such as a 250mm f/4, or a 300mm f/4 (that one for 8x10). You can find the information on LF Sonnars on pages 13-17 of my recent article on Zeiss Oberkochen LF lenses: http://www.arnecroell.com/zeissoberkochen.pdf

[Bernice Loui]

The Sonnar is a Tessar variant.. consider this for a moment.

There are longer focal lengths lenses with large aperture available for 4x5 sheet film and larger. Most of them were made for military aero-recon. Kodak made a 305mm f2.5 Aero Ektar, it is HUGE and heavy comes in a Fairchild K38 shutter and easily covers 8x10. Others have been made by Perkin Elmer, Pacific Optical, Diffraction Optics, Bausch & Lomb and others. In the past, many of these HUGE lenses were sought after by hobbyist astronomers to be made into refractor telescopes. Most of these are a serious problem to use as a view camera lens due to their size, weight and...

Video of the Fairchild K38 shutter, there is enough power in the shutter blades to instantly slice off a finger..
http://www.youtube.com/watch?v=BJ_db1cg6ao


Bernice

[Corran]

Video of the Fairchild K38 shutter, there is enough power in the shutter blades to instantly slice off a finger..
http://www.youtube.com/watch?v=BJ_db1cg6ao

That is awesome!

[Dan Fromm]

The Sonnar is a Tessar variant.. consider this for a moment.

Look again. Triplet. So what? Sonnars pass light and form images. What more could anyone want?

There are longer focal lengths lenses with large aperture available for 4x5 sheet film and larger. Most of them were made for military aero-recon. Kodak made a 305mm f2.5 Aero Ektar, it is HUGE and heavy comes in a Fairchild K38 shutter and easily covers 8x10. Others have been made by Perkin Elmer, Pacific Optical, Diffraction Optics, Bausch & Lomb and others

Not all. Post 37 in this thread mentions Dallmeyer's Super Six. The longest Super Six is 8"/2.0. Not a lens for aerial cameras, nor is the 250 Sonnar mentioned in this thread. Post 37 also mentions a 200/2.0 S.F.O.M, definitely a lens for an aerial camera. Your list of makers of lenses for aerial cameras is much too US-centric and it misses many makers. See the USAF data sheets at http://archive.org/details/USAF_lens_datasheets for a longer, still incomplete, list of makers, not all in the US. For some Soviet aerial camera lenses, see the 1963 GOI catalog, download it from http://www.lallement.com/pictures/files.htm. For some Elcan aerial camera lenses, see elcan lenses.pdf, download it from http://sdrv.ms/1eNSw9n.

See the VM, second edition, file 008ljm.pdf, "Military Optical Ordinance," pages 79 - 81 for a discussion of how usable lenses from aerial cameras aren't. The idea that they're basically doorstops isn't new.

With, however, the rise of ancient, now called alternative, processes some of those monstrosities are turning out to be surprisingly usable. See this recent discussion here http://www.largeformatphotography.in...Trailer-Camera. Its hard to see what the lens in the video it links clearly to but it sure looks like a long fast aerial camera lens. Coupla years ago I gave a 36"/8 B&H monstrosity to a forum member who told me he was going to use it for wet plate.

For most of us, though, the majority of fast lenses from aerial cameras are, as you pointed out, doorstops. Some, not all, shorter ones for cameras that shot 6x6 or thereabouts on 70 mm or thereabouts film are usable, but they're for MF, not LF.

[Misko]

If you want fast Ernemann build some Ernostar LF lenses. The Sonnar is based on the Ernostar design.

I've just started Ernostar discussion few days ago in the Lenses part of the forum and here are two photo examples of that amazing design!
Wide open Ernemann Ernostar Anastigmat 18cm f2.7: http://www.flickr.com/photos/milosgazdic/10414764645/
and
Stepped down to f16 Ernemann Ernostar Anastigmat 18cm f2.7: http://www.flickr.com/photos/milosgazdic/10203758323/

(If someone could explain me how to properly link photos from Flickr to the forum I would be thankful)

[David A. Goldfarb]

Just checking to see what I have conveniently scanned with the Zeiss 135/3.5 Planar--


f:4, Fuji RMS, Linhof 4x5" Tech V with 6x7cm back


f:4, TXP/Acufine, Linhof 4x5" Tech V

[E. von Hoegh]

Look again. Triplet. So what? Sonnars pass light and form images. What more could anyone want?

The original Sonnar was an f:4.5, designed by Bertele, and made by Contessa-Nettel for their folding cameras. I had one, until I actually disassembled it I thought it was a Tessar under a different name - the second 'element' was actually a cemented triplet, and it behaved like a Tessar with better corners at wide apertures. When Zeiss bought out Contessa-Nettel, they used the name on a somewhat similar design of Bertele's, a fast lens for the Contax and so a legend was born...

[Ian Greenhalgh]

The Sonnar is a triplet derivative in the same way that the Heliar and Hektor are triplet derivatives - a front positive group, a centre negative group and a rear positive group. The Tessar also fits this pattern but was derived from the Unar and Protar.



Heliar - replaces the front and rear elements with cemented pairs:


Hektor - replaces all three elements with cemented pairs:


Thambar/Hektor -replaces the centre element with a cemented pair:

[Ian Greenhalgh]

The Sonnar's lineage is through the Ernostar types, the original basic Ernostar was a triplet with an extra front element:


The Ernostar design went through several changes, the f2 of 1924 replaced the second element with a cemented triplet:


The f2 Sonnar of 1931 is a revision of the f2 Ernostar where the rear two elements are combined into a cemented pair:


The f1.5 Sonnar came a year later in 1932 and had a rear cemented triplet replacing the cemented pair:


The main thing that strikes me is how brilliant and elegant a design the original triplet was. It has full correction of the main aberrations with only 3 elements and no cemented pairs, the Tessar uses it's rear cemented pair to correct achromatism, the triplet manages the same correction without any expensive to manufacture cemented pairs and imho, is the true foundation of modern optics.