Thanks for your effort Andy, will be looking for the SA. But, the EM seemed to have a greater tonal range based on your scans (?).

Which other past or present Leitz/Leica lenses in the wide angle world are non/retrofocus by design? Personally, I've always avoided retrofocus lenses like the plague.

-- Steve (leitz_not_leica@hotmail.com), April 04, 2002

Answers

I have a 21mm R lens from the 1960s (I believe - I'm no expert) along with an adaptor to allow it to be used with an M. The lens was apparently designed to be used in a mirror lock-up mode and thus (I am told) it is not a retrofocus lens. Because it's an R lens, it doesn't couple to the rangefinder, and needs a separate viewer. It takes a 67mm filter size.

I'm actually thinking of selling/trading it and getting a new ASPH lens with a somewhat less extreme viewpoint - say a 24mm or a 28mm. Let me know if you're interested

-- Ben Crabtree (bcrabtree@mn.rr.com), April 04, 2002.

My previous comment:

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Well done Andy! I like it a lot. Well if there was anything you, and we all shoudl've learnt from the "Erwin Puts test reports" post is, is that submitting the "actual" pictures used in the review process is a great way of supporting your claims. Sure they could've been taken from anywhere with any lens, but if the review is consistent with what can be seen in the images, the credibililty of the review increases.

As seen here from Anydy's accomplished efforts. And his english was clear and understandable, quite unlike some of Erwin's reviews (see end of 90APO review against 80/1.4). No racism intended! It just helps to read something understandable in relatively plain english. (my english is far from perfect!). -- Kristian (leicashot@hotmail.com), April 04, 2002.

-- Kristian (leicashot@hotmail.com), April 04, 2002.

The question was what Leica/Leitz [wideangle]lenses are/were non- retrofocus. To answer the question accurately, there were no *Leitz/Leica* non-retrofocus wideangles. The 21/4 S/A (the rangefinder model, not the R lens), the 21/3.4 S/A (M and R), and the 15/8 Hologon were all non-retrofocus...but the S/A's were Schneider lenses and the Hologon was a Zeiss.

-- Jay (infinitydt@aol.com), April 04, 2002.

I forgot to say that my 21mm non-retrofocus lens is a Super Angulon f3.4 also.

-- Ben Crabtree (bcrabtree@mn.rr.com), April 04, 2002.

I onīt have my books at hand, but if remember well; Leica M system had a 21/4 Super Angulon (symetric, from Schnider)as itīs first 21(this was too for the SM), then again from Schnider a 21/3.4 also symetric, Elmarit and Elmarit asph both Leitz designs came later.

On the other side Leica refles system had first the 21/3.4 symetric from Schnider, and it needed the reflex mirrow to be put up and from a finder in the shoe the view; later came a 21/4 super Angulon on a retrofocus design, now mirrow could be put down.

Just add that I also liked this post from Andy,

-- r watson (al1231234@hotmail.com), April 05, 2002.

I believe Leica's first 28 f/2.8 (1965-72) was non-retro - at least it extended so far into the camera that it couldn't be used with the M5 meter - or on the CL at all. And it was actually a Leica design.

Also all the screw-mount wides (28 Hektor 6.3/Summaron 5.6) - which can, of course, be mounted on an M with an adapter.

28's have always been sort of a Leica step-child, though - They had the Schneider 21 f/4 for years while still selling only a 5.6 in the 28.

-- Andy Piper (apidens@denver.infi.net), April 05, 2002.

Are any of the pre-asph 28/35 generations retrofocus?

Are the 21/24/28 Asph. retrofocus?

What is the difference between tele and non-tele 90/135 designs? I've seen mentioned "...is a true tele..."

-- Steve (leitz_not_leica@hotmail.com), April 05, 2002.

retrofocus long lenses are shorter that itīs focal length, and retrofocus short lenses can be longer than itīs focal length alowing the use of a swinging mirrow in the SLRs or ligth meter in a RF.

-- r watson (al1231234@hotmail.com), April 05, 2002.

every 35 i've seen, then, seems to be retrofocus since the rear element does not protrude that much, i must say a little disappointing given it's my favorite focal length.

-- Steve (leitz_not_leica@hotmail.com), April 05, 2002.

Steve, the 35mm lenses are not retrofocus, and don't need to be, since the rear element does not protrude into the camera even with true wideangle design at that focal length. The rear element remains slightly recessed behind the bayonet mount.

-- Bob Fleischman (RFXMAIL@prodigy.net), April 05, 2002.

There's nothing to be disappointed about. They are true wideangle lenses, and that's a good thing.

-- Bob Fleischman (RFXMAIL@prodigy.net), April 05, 2002.

In a 'long-focus' lens (e.g. your basic magnifying glass, the 2-element 400 f/6.8 or the original 90 Summicrons/Elmarits for the M, among others) - when focused at infinity - the distance from the optical center of the lens to the film is equal to the focal length.

"Telephoto" lenses (90 APO 'cron, Tele-Elmarit) are designed so that the overall length of the lens is shorter than the optical length. They have positive (convex) elements in the front - and negative (concave) elements in the rear that ast as sort of a telconverter to increase the magnification without increasing physical length as much.

In true wide-angles - like long focus lenses - the distance from the optical center to the film at infinity equals the focal length.

Retrofocus designs are like (and occasionally called) reverse telephotos. They have concave glas in the front and convex (more or less) elements in the back. They are roughly equivalent to using one of those wide-angle adapters made for video/digital cameras - a big 'minifying' lens in front that makes everything look smaller without actually having to move the rear elements closer to the film - thus leaving room for SLR mirrors or M5/6/7 metering.

Note that the optical center of a lens is an idealized point in space. In real lenses the various chunks of glass take up 3D space - so the rear element of the 21 Super is actually only about 5-6mm from the film, and the front element of the original 'big' 90 Summicron is actually (geez, I don't know) at least 100mm (4") from the film.

There's a great Korean web site that shows the optical construction of all the Leica lenses - but I don't have it bookmarked here - I'll have to add a post Sunday with the link. There you can see that (for example) the original long 90 'cron, the 50 'crons, and the 35 'crons (preASPH) all actually have very similar designs (Double-Gauss to be exact) The size is just tweaked to change the focal length. Also the differences that make a telephoto a telephoto and a retrofocus a retrofocus.

-- Andy Piper (apidens@denver.infi.net), April 06, 2002.

Lens optical layout link Go to the bottom to switch between multiple pages - Leica M and Leica screw-mount are both available.

-- Andy Piper (apidens@denver.infi.net), April 07, 2002.