World's First Aspherical SLR Lens?

The thing about writing a blog is that, well, one thing leads to another. Yesterday in the post about Nikon's new 58mm lens, I called the Noct-Nikkor 58mm of 1977 "the world's first aspherical SLR lens." I think this was my mistake, based on a misreading of the materials I read prior to writing the post.

Old friend Chuck Westfall of Canon USA contacted me to partially correct this—he's the one who provided the link to the aspherical Canon FD 55mm ƒ/1.2 AL, first marketed in March of 1971. I made the change in the post.

(By the way, most of these older lenses are now collector's items.)

But wait!
Later, Chuck looked into the matter a little further, and found (no surprise) a further wrinkle to the story. The first aspherical lens for an SLR was actually a Nikon lens after all. It was the OP Fisheye-Nikkor 10mm ƒ/5.6, announced in 1968 and discontinued in 1976. Chuck wrote, "You might recall this lens; it was Nikon's third fisheye for F-mount SLRs, following the 8mm ƒ/2.8 and 7.5mm ƒ/5.6 models, but the first one to feature orthographic projection rather than the more conventional equidistant projection design of the earlier fisheye lenses." Nikon has a great web page on the history of its fisheye lenses.

So does this settle the matter? Not quite—and here comes the wrinkle. The back elements of the OP Fisheye-Nikkor 10mm ƒ/5.6 extended so far into the mirror box that the lens could only be used on SLRs with the mirror locked up! So it could be used on SLR cameras, but not when they were being used as SLRs. Also, it didn't support auto aperture stopdown.

So while the Nikon fisheye perhaps walks away with the "first ever" honors, the Canon FD 55mm ƒ/1.2 AL is really the first aspherical lens for SLR cameras that supported both reflex viewing and automatic diaphragm operation—in other words, the first one you could use on an SLR as SLR lenses are normally used.

Cross section of the Canon 55mm ƒ/1.2 AL, from the Canon Camera Museum.

Oh, and by the way—why isn't Nikon's new 58mm an ƒ/1.2 lens, if it's really intended to be an homage to the 1977 Noct-Nikkor? The answer is that to do so would make it too big, heavier, and even more expensive, with little in the way of payoff. And there's just no need. In 1977, high-speed film was ASA (as it was called then) 400, and you could squeak out E.I. (exposure index, as any departure from the rated ASA or film ISO was correctly called) 1600 if you used special developers and were willing to accept a heavy image-quality hit. Now, many digital cameras can shoot natively at ISO 3200 with quite acceptable quality. Really, even an ƒ/1.4 open aperture is primarily for viewing convenience and DoF effects, not because it's needed for exposure speed—and the half stop between ƒ/1.2 and ƒ/1.4 is largely irrelevant.

Mike
(Thanks to Chuck Westfall and Ctein)

Original contents copyright 2013 by Michael C. Johnston and/or the bylined author. All Rights Reserved. Links in this post may be to our affiliates; sales through affiliate links may benefit this site.

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Featured Comments from:

Jeff Ralph: "Here is an interesting review of the Canon 55mm from the May 1978 issue of SLR Camera magazine."

Comments

[Gregg]

It is approximately 0.47393118833241233283316097108315 stops faster...

[GH]

I realize that is isn't an SLR lens, but, for what it is worth, the Leica 50/1.2 Noctilux aspherical came out in 1966.

[Sebastian]

> (Ctein could tell us what the fraction is—it's not half)

Actually, it's very nearly half. Exactly half would be f/1.189; a third stop down from f/1.4 would be f/1.26, two thirds f/1.122. The case of f/1.2 is a little confusing because manufacturers usually round both the half-stop and the two-thirds-stop increment to /f1.2.

Generally, f-numbers are simply multiples of the square root of 2 (which is why f/1.4 is actually f/1.414).

[Nikojorj]

To add a bit to the "Why isn't the new 58mm a f/1.2?" question : there is also the fact that digital sensors don't benefit much from very oblique incident light rays, and the supplementary rays going from f/1.4 to f/1.2 are generally very oblique in the corners.
See http://www.dxomark.com/Reviews/F-stop-blues : in short, digital sensors don't benefit that much from large aperture lenses.

[Eric Rose]

I'm tired of all these endless "upgrades". I will not get excited until either Nikon, Canon or even Sony produces a pro level SLR with an upgradeable sensor and firmware to go along with it. My D700 is built like a brick shit house. Heck it will probably outlast me! But according to pundits it's a dinosaur. No matter it does everything I want it to.

What does this have to do with a useless focal length lens that's not fast enough and costs $1800CAD? Nothing really, I'm just venting.

It seems that once digital took over all the major camera manufacturers lost their minds.

I say we name this new 58mm lens the "Edsel".

[Jeff Ralph]

Here is an interesting review of the Canon 55mm from the May 1978 issue of SLR Camera magazine.

[Colin Work]

Best thing about the review Jeff points to is that the body the lens is mounted on is an AT1 - my first in a long line of camera bodies.

Lots of good memories - probably the only body I've replaced 'cause I wore it out.

[Esa Kivivuori]

The Leica Noctilux 1:1.2/50 mm (1966) was the first 35mm camera with an aspherical element.

[Hi Esa, The subject here is SLR lenses. --Mike]

[Adam Maas]

There's a very simple reason why it isn't an F1.2 lens, and that is that the rear element would be too large for the throat of the mount on a CPU-equipped lens. The tab that holds the lens contacts on modern Nikon lenses limits the size of the rear element to smaller than what was possible with mechanically coupled lenses, including all 3 of the f1.2 lenses made in F mount (the 50, 55 and 58mm)

[Carsten W]

Mike, have you taken a look at the MTFs compared to the Noct-Nikkor? The closeness of the sagittal and tangential lines is astounding, and they are also surprisingly flat until well out in the field. I am guessing that this lens will have stunning boke... Yes, I use the pre-h spelling by preference :)

P.S. I see I am not the only FMer here: Adam even wrote what I wanted to write before I got there :)

[ctein]

Dear Sebastian,

As a matter of fact, our semi-innumerate [g] editor DID ask me... and I told him one half.

No one ever talks about this stuff closer than 1/12th stop (i.e., is something closer to 1/2 than 1/3 or 2/3).

pax / Ctein