So, why 40mm lens?

V

Vickko

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I am curious, why are there 40mm lenses, when 50mm was the historical "normal" focal length, and 35mm the traditional "first step into wide angle"?

I love my 40mm Summicron, as much as I like using my little CL.

But the CL is the only M camera with 40mm framelines.

I see the 40mm Nokton in the ads, and it made me wonder - why are there 40mm lenses?

Vick
 
"But the CL is the only M camera with 40mm framelines."

Actually, the Bessa R3* also has 40mm framelines, as does the Minolta CLE.

Tom A. has posted comments in the past on the virtues of the 40mm focal length, and there's an interesting article by Mike Johnston over on the Luminous Landscape on 40mm lenses. It is sometimes remarked that 40mm is the "true normal" focal length for a 35mm negative; I don't know whether that's really correct or not.

For me, it's the specific lens that makes the 40 attractive: the Rokkor 40/2 CLE version, which produces results like a 35 Summicron at a fraction of the price. In fact, I shoot that lens in situations where I would otherwise use a 35, and appreciate the tighter framing.
 
i like 40, had it on my cle kit, very nice...and surprisingly, i also like it on the rd1, even with the crop factor.
 
I guess it was Leica with their CL that pushed the 40mm lens. They must have felt that a 40mm lens was a useful focal length replacing the traditional 35 and 50 combo. They must have also thought that a 40/90 2 lens combo was the ideal small kit to go along with their new Compact Leica body.

Anther notable camera maker that thought highly of the usefulness of a 40mm lens was Rollei with the fixed 40mm Tessar and Sonnar on their compact 35 camera models.
 
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There are two reasons, and both are one: it's the only focal length that's not clearly wide nor clearly tele, so it can be used for both looks sometimes, being the best all around focal length... And it's geometrically the closest focal length to a "normal" lens: it has the size of the frame's diagonal...(Near 43mm as the 40 Nokton)

Cheers,

Juan
 
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Juan Valdenebro said:
There are two reasons, and both are one: it's the only focal length that's not clearly wide nor clearly tele, so it can be used for both looks sometimes, being the best all around focal length... And it's geometrically the closest focal length to a "normal" lens: it has the size of the frame's diagonal...(Near 43mm as the 40 Nokton)

Cheers
Click to expand...

I was about to post a similar comment Juan. Pentax makes a 43 mm lens for just that reason.

I love the 40; the 40/2 Rokkor is one of my favorites and the reason I went for an R3A as my first RF. I seem to recall a thread from a year or so ago about the 40 FL and if memory serves, someone commented about the versatility of a 40 - take a step or two forward and it's like a 50, a step or two back and it's like a 35. If I'm going to be using one lens, one camera, it's my favorite FL.
 
Yes, and the rokkor is superb and small... I think I read Roland found the rokkor and the nokton both great on a comparative test he did some time ago...

Cheers,

Juan
 
Perhaps Mr. Kobayashi enjoyed the 40mm Summicron/Rokkor too, as it's said that his favorite focal length is 40mm. This probably lead to the Voigtlander 40mm Ultron and Nokton lenses, and the (world's only?) 40mm accessory viewfinder.

I have found the 40mm Rokkor and CLE extremely useful, and still favor this +/- angle of view across various formats.
 
I love my CV 40mm, fast, light, small and very versatile and let's not forget the 80mm for the Mamiya 7 is equivalent to a 39mm.
 
As stated, if you do the basic geometry, 43mm is the closest focal length to a true "normal" as determined by the diagonal of the 24mm by 36mm frame. A lot of fixed lens rangefinders (Rollei, Yashica Electro 35, Minolta Hi-Matic, and others, used 40, 42, and 45mm lenses and I suspect when the CL was developed, given its size, it was meant in part to compete in the market for those very small fixed lens rangefinders, with the added benefit of interchangeable lenses. Anyway Erwin Puts in the Leica Lens Compendium writes about Leica's early 35mm lens development, when they were the only game in town, and on the choice of 50mm.

I liked my old 40mm Summicron a lot until I drunkenly left it in a cab, attached to a lovely CL. Major reason I stopped drinking in fact. I also like Minolta's MD Rokkor 45mm f/2 and I pine for the Nikon 45/2.8 they put out a few years back. These days I'm finding that 45 is a little more vivid and muscular than 40. My final thoughts on this topic: people with the Lumix GF1 in particular as well as G1 and G2 users, worship the Lumix 20mm f/1.7 lens which really does appear to be outstanding; and of course on the m43 sensor that is essentially a 40mm lens. Of course when we're working in digital we do a lot of cropping so it's hard to say what a lens looks or feels like after we're done with it in p.s.
 
The framelines in later Leicas (late M4P; M6; MP) are all undersized, with the 50mm being the worst of all. The 35mm frameline is a nearly exact match for a 40mm field of view. For this reason I often use my 40mm Rokkor or my 40/1.4 Nokton with my M6 and MP bodies. I will use my 35mm lenses too, of course; but lately I'm as likely to use them on the M2 as on M6 or MP. Rangefinder framing is seldom precise; but with a 40 on the M6 or a 35 on the M2, it's "good enough."
 
The Bronica RF 645 (medium format rangefinder) has a 65 mm as their standard lens that is a roughly 40mm equivalent.. The 40mm lens is roughly a 28 and I love the combination of the two.
 
Tessar 40/3.5 on Rollei 35, 80/4 on Mamiya 7 (39mm equiv) and Panny 20/1.7 (40mm equiv) are my favorites.

CV 40/1.4 SC was very nice and I might get another copy in the future...
 
Early fast 'normal' lenses were often longer than 50mm -- many at 55mm/1.8 (Pentax), even a 58mm/1.4 (Minolta). At the time it was a bit easier to design a fast 55 or 58 than a fast 50.
 
Nobody mentioned the 45mm Planar for Contax G? That lens just felt so right to me (and not to mention had the benefit of rendering color that could knock your socks right off).

Aren't the 75mm Xenotars, Xenars, Planars on Rollei TLR's also effectively around 43mm in 35mm focal length?

I love anything in the 40's and wish there were more out there. I SO want another 40mm Voigtlander Ultron SLII for my SLR. I used to have one and stupidly sold it.
 
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