What's the story behind 40mm focal length?

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psychoanima

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Hello all,


I am looking for another rangefinder (owning Oly XA, FED3 and Leica M9) for my street photography work. I am more and more into film photography and I am reading a lot of reviews/tests/what not, and although there is a lot to choose from, especially rangefinders with fixed lens from 70's, they mostly, if not all, have 40mm lens. My preferred focal length for street is 35mm. 50mm is too much narrow and 40 is still not wide enough. I like to be closer to the subject and with zone focusing, shot and gun, I mostly behead or miss focus the people on 40 and 50mm, and I am wondering what is the story behind 40mm in fixed rangefinders? XA has 35mm but 35RC/SP - which has been said, are tremendous rangefinders - are having 42mm lenses. Voigtlander even continued after with this focal length on their Bessa rangefinders. Why?

On another note, I am looking for a compact rangefinder with 35mm lens (not fully automatic) and despite how much I love XA, I am looking for something sharper for printing work. I guess that at some point I will fall for analogue Leica, but still, for my street style I need something less intrusive.
 
I think it's easier to use and easier to make than a wider lens.
If you must have a 35mm lens in a compact rf, there are a few options. One is the Yashica 35 CC, brilliant camera, except the triangular aperture. Plus a few of an older generation, from the late 50s to early 60s I believe, that are rather obscure and usually carry the suffix "wide" or "w" in their name.
 
I’ve been a 50mm fan for the last 8 years or so. Swore by it. Then all of a sudden, I now love 40mm... it just feels right. Wide but not too wide, but still looks normal.
 
Using a CV R3A with a CV 40/1.4 is what got me going again on RF's back in 2005 after a 20 year hiatus.
 
when you are looking for sharpness in prints then probably a Barnack would meet your criteria, smallest form factor, modern glass possible.

edit: I just forgot that the viewfinder doesn't work for 35mm:rolleyes:
 
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My guess is that 40mm was the widest manufacturers could go in the early 70s by stretching an affordable 50mm lens design that they already had. Fast 35s were difficult and expensive to make at the time, and consumers wanted something wider and more versatile than the 45-50s that came standard on most cameras of the era.
 
As was mentioned in lens design, 40mm is probably the widest focal length with decent quality that can be stretched from established design (at the time.) The physical size must be compact as well and don't forget, the 50mm lens was the 35mm normal and often, the only lens a camera owner would regularly use. So, many manufacturers weren't stretching wider, they would have been trying to get a design as close to normal but as compact as possible.

Phil Forrest
 
A 40mm lens is "nearly as wide" as a 35mm lens, and "nearly as easy" to produce as a 50mm lens. It is two-for-one. It never grew on me. I have the Summicron-C 40/2 and also a Pentax-L 43mm/1.8 and a Rollei 40mm/2.8. Each of these three lenses is a wonderful lens. Then why don't I use them more often? Maybe it is the awkward focal length?
 
40mm is very close to "normal" for the format. 50mm is just a carryover artifact from Leica's early choice. 40mm might actually mean 42mm anyway, just as 50mm usually means something closer to 52mm with Leica.

In theory it is a wonderful focal length and very popular. I have the great 40mm Summicron and just cannot manage to adapt to the focal length. I take it out once in a great while, but always wish I had either a 50 or 35mm instead.
 
I think Barnack used a 40mm lens in his prototype, amongst many others. The appeared in the 1910 catalogue. My guess is that is was used off the shelf like a lot of other parts for the camera; which explains the odd screw thread...


Regards, David
 
Mark C said:
In theory it is a wonderful focal length and very popular. I have the great 40mm Summicron and just cannot manage to adapt to the focal length. I take it out once in a great while, but always wish I had either a 50 or 35mm instead.
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The focal length is best appreciated when you have the frame lines (Bessa) or WYSIWYG on an OM or CaNikon body with a Zuiko or Voigtlander lens, respectively.
 
My theory is that these cameras were aimed at the amateur market, so manufacturers provided them with a shorter lens that would give more depth of field (hence more overall sharpness, hence "better" pictures). At the same time, consumers were developing a sense that a faster lens was a "better" lens, but the larger maximum apertures offered less depth of field. I think that the choice of a shorter lens with a large maximum aperture was the manufacturers' way of solving a dilemma that had been created by their own marketing strategies. In an earlier era, enthusiast amateurs seem not to have been so much enamored of overall sharpness in a picture. Films were slower, and formats larger, and hyperfocal distance less easy to achieve; an out-of-focus background seems to have been more accepted. I've noticed this in my own family photo archives from before WWII, and it may have been the norm. Overall, I think that amateurs' basic expectations of what a good photo should look like went through a rapid process of change after the war, perhaps due to the huge influx of higher-end consumer goods (including cameras) at that time. The influence of technology on "seeing", even for those not concerned with anything but snapshots, can be a fascinating area of research.
 
David Hughes said:
I think Barnack used a 40mm lens in his prototype, amongst many others. The appeared in the 1910 catalogue. My guess is that is was used off the shelf like a lot of other parts for the camera; which explains the odd screw thread...


Regards, David
Click to expand...

That it was "off the shelf" is one idea that has been suggested in the past several years. But this is the first indication that Barnack's first lens was a 40mm. I've never seen that 1910 catalog. This is new data for me!
 
One reason for using a 40mm with Leica M models from the M6 and forward, is that Leica shrunk the frameline sizes for these models. So the 40mm lens is a good match for their 35mm framelines. Unfortunately, most 40mm lenses, such as the 40mm Summicron, Minolta Rokkor, and my Voigtlander 40/2, bring up the 50mm framelines. I file the cam to make them bring up the 35mm frameline for these lenses.

It's only at the minimum focus distance of 0.7M (28 inches) that the 35mm lens field of view will match the framelines on the M6, M7, or MP. They made this change around the time they reduced the minimum focus from 1M to 0.7M.

So with an M2, M3, M4, or M5, the 35mm lens will match the camera finder's FOV at shooting distances that are well beyond the minimum focus (say, 7 0r 8 feet and beyond). For any Leica from a late model M4-P and forward, the 40mm comes closer.

The only gross mismatch is with the 50mm framelines on those later models. They cover the field of a 60mm lens, meaning they match no lens made for the Leica M mount. For this reason, I will only shoot a 50 on my M2, M4P, or M5.
 
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