So how did the standard lenses become standard? 28mm, 50mm, 135mm

[Solarflare]

Designs around 50mm relative to "full frame" or however you want to call a 36x24mm aka 43.3mm diameter design simply results in very compact lens designs.

You dont have to do any trickery like telephoto (for not too long long lenses) or retrofocus (to make wide lenses even possible for SLRs) designs.

 

[table1349]

The Beginning


1 In the beginning God created the heavens and the earth. [SUP]2 [/SUP]Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters.

[SUP]3 [/SUP]And God said, “Let there be light,” and there was light. [SUP]4 [/SUP]God saw that the light was good, and he separated the light from the darkness. [SUP]5 [/SUP]God called the light “day,” and the darkness he called “night.” And there was evening, and there was morning—the first day.
[SUP]6 [/SUP]And God said, “Let there be a vault between the waters to separate water from water.” [SUP]7 [/SUP]So God made the vault and separated the water under the vault from the water above it. And it was so. [SUP]8 [/SUP]God called the vault “sky.” And there was evening, and there was morning—the second day.
[SUP]9 [/SUP]And God said, “Let the water under the sky be gathered to one place, and let dry ground appear.” And it was so. [SUP]10 [/SUP]God called the dry ground “land,” and the gathered waters he called “seas.” And God saw that it was good.
[SUP]11 [/SUP]Then God said, “Let the land produce vegetation: seed-bearing plants and trees on the land that bear fruit with seed in it, according to their various kinds.” And it was so. [SUP]12 [/SUP]The land produced vegetation: plants bearing seed according to their kinds and trees bearing fruit with seed in it according to their kinds. And God saw that it was good. [SUP]13 [/SUP]And there was evening, and there was morning—the third day.
[SUP]14 [/SUP]And God said, “Let there be lights in the vault of the sky to separate the day from the night, and let them serve as signs to mark sacred times, and days and years, [SUP]15 [/SUP]and let them be lights in the vault of the sky to give light on the earth.” And it was so. [SUP]16 [/SUP]God made two great lights—the greater light to govern the day and the lesser light to govern the night. He also made the stars. [SUP]17 [/SUP]God set them in the vault of the sky to give light on the earth, [SUP]18 [/SUP]to govern the day and the night, and to separate light from darkness. And God saw that it was good. [SUP]19 [/SUP]And there was evening, and there was morning—the fourth day.
[SUP]20 [/SUP]And God said, “Let the water teem with living creatures, and let birds fly above the earth across the vault of the sky.” [SUP]21 [/SUP]So God created the great creatures of the sea and every living thing with which the water teems and that moves about in it, according to their kinds, and every winged bird according to its kind. And God saw that it was good. [SUP]22 [/SUP]God blessed them and said, “Be fruitful and increase in number and fill the water in the seas, and let the birds increase on the earth.” [SUP]23 [/SUP]And there was evening, and there was morning—the fifth day.
[SUP]24 [/SUP]And God said, “Let the land produce living creatures according to their kinds: the livestock, the creatures that move along the ground, and the wild animals, each according to its kind.” And it was so. [SUP]25 [/SUP]God made the wild animals according to their kinds, the livestock according to their kinds, and all the creatures that move along the ground according to their kinds. And God saw that it was good.
[SUP]26 [/SUP]Then God said, “Let us make mankind in our image, in our likeness, so that they may rule over the fish in the sea and the birds in the sky, over the livestock and all the wild animals,[SUP][a][/SUP] and over all the creatures that move along the ground.”

[SUP]27 [/SUP]So God created mankind in his own image,
in the image of God he created them;
male and female he created them.

[SUP]28 [/SUP]God blessed them and said to them, “Be fruitful and increase in number; fill the earth and subdue it. Rule over the fish in the sea and the birds in the sky and over every living creature that moves on the ground.”
[SUP]29 [/SUP]Then God said, “I give you every seed-bearing plant on the face of the whole earth and every tree that has fruit with seed in it. They will be yours for food. [SUP]30 [/SUP]And to all the beasts of the earth and all the birds in the sky and all the creatures that move along the ground—everything that has the breath of life in it—I give every green plant for food.” And it was so.
[SUP]31 [/SUP]God saw all that he had made, and it was very good. And there was evening, and there was morning—the sixth day.

God looked around all that he had made and decided that there needed to be a way to record this spender and he created silver iodide on copper plate. God then created a box free of light except for a small hole. Opposite that hole he created a slot to place a copper plate and photography was born. Good looked at his creation and saw that it was good.

God saw that his creation was time consuming and difficult to use so he created nitrated cotton dissolved in ether and alcohol and chemicals on sheets of glass. God was pleased at the ease of this new creation. God watched as man took his creation and ran with it. To God's great consternation he saw that man had in a willy nilly(an ancient Hebrew expression) fashion created a multitude of devices, all of which would not work together.

To solve this issue God in his Greatness and Wisdom set forth and created film of specific sizes and bodies to house them. He then set forth and created standardized focal lengths for lenses so that all could understand the greatness of his creation. These focal lengths were created based on knowledge that only God holds, and is one of the great mysteries of life. And God looked around at all he had created and was satisfied for it was good.


Should we really be questioning that which God has made?

 

[Ysarex89 83]

A lens is considered "normal" if its focal length is close to the diagonal of the format. 135 film has a diagonal of about 43mm, so any lens near that is a "normal" lens. 50mm also happens to have the same magnification in many 35mm SLR viewfinders as an unaided eye. I think this is also where the myth that a 50mm lens has the same "perspective" as the human eye came from....

:thumbup:

Yes, a normal lens focal length matches the diagonal of the film format. Very good point about the viewfinder magnification. Pentax sold their 6x7 beast with a 105mm normal that exactly matched the viewfinder magnification so you could use the camera with both eyes open -- one looking through the viewfinder and the other seeing the larger scene -- a strange sensation.

And yes the "human eye perspective" reason is a myth both because that's not why normal lenses are normal and because normal lenses do not match the perspective seen by the human eye. The human eye does not have a perspective and neither do lenses.

Joe

 

[BrianV]

Oscar Barnack picked "50" to make for his first Leica in 1913. He used strips of 35mm movie film, exposed horizontally. I've read "somewhere" that 50mm lenses were popular for movie cameras of the day, a "Portrait" length. The first trial run Leica featured a 50mm F3.5 "Anastigmat" lens. Leica rangefinder cameras used 51.6mm for their standard length, Zeiss used 52.4mm for the Contax. Nikon and the other Japanese manufacturers followed the Leica standard after WW-II, the Russians followed the Zeiss standard. Most modern SLR lenses are closer to 51.5mm. It is only important to get the exact focal length correct when you want to use a lens on a Rangefinder camera. I've altered focal length on a couple lenses to make them work.

I have a 2.04in (51mm) F1.5 Wollensak Raptar. I need to make it into M-Mount.

 

[Derrel]

I like the 51 mm lens the best.

My very first-ever "serious" camera had a Kodak 51mm Anaston f/4.5 lens...seriously...51mm...

il_fullxfull.345972404.jpg

Many 50mm lenses are actually shorter or longer than 50mm when measured accurately. I think many Nikkor 50's are actually 48.5mm.

 

[Derrel]

As to the viewfinder magnification issue...Herbert Keppler of Modern photography magazine wrote an article a long time ago on lens lengths...as I recall, he mentioned that the early Nikon F (and other brand) cameras had viewfinder magnifications that gave 1:1 or "both-eyes-open" viewing with 58mm lenses...and later, as viewfinder magnifications changed, the 50mm became the "new normal" for SLRs. Of course, the 5cm lens focal length had been pretty standard on hundreds of 1930's-1970's 35mm viewfinder and coupled rangefinder camera designs.

If I recall the early 1970's correctly, there were a good number of old,used Exacta, Exakta (how many spellings on that brand were there?!) and other European 35mm SLR's from the early 1960's to mid-60's that had 58mm lenses as their "normal". My third "serious" camera was a Russian-made Cosmorex SE, bought from Cambridge Camera, in NYC; the "Cosmorex" was their brand of the Zenit-B 35mm SLR...a roughly-made and poorly-finished camera that came with an m42 thread mount 58mm f/2 "Auto-Cosmogon" lens, if my memory serves me correctly. It was definitely a 58mm lens.

On 35mm, I actually LIKE the 58mm lens. Cosina has recently made a few of them, over the past half decade or so. 58mm is a nice length for a walkabout/landscape/scenic lens...it's a lot narrower than 50mm...much more-selective in its view...not nearly the same thing as a 50!

 

[enzodm]

If I recall the early 1970's correctly, there were a good number of old,used Exacta, Exakta (how many spellings on that brand were there?!) and other European 35mm SLR's from the early 1960's to mid-60's that had 58mm lenses as their "normal". My third "serious" camera was a Russian-made Cosmorex SE, bought from Cambridge Camera, in NYC; the "Cosmorex" was their brand of the Zenit-B 35mm SLR...a roughly-made and poorly-finished camera that came with an m42 thread mount 58mm f/2 "Auto-Cosmogon" lens, if my memory serves me correctly. It was definitely a 58mm lens.

Exakta had the Zeiss Jena Biotar 58/2 (a pre-war design, double Gauss, then renamed Planar by western Zeiss), which russian copy was the Helios 58/2 part of the Zenit base kit and perhaps the most sold lens of every time. I did not know it was sold also in US, but I'm sure your Cosmogon was one of them. They were sold also under some chain brand name (maybe Revuenon or so).
Here Zenits have been for long the entry level SLR, as a student I had two. Their main issue was failure of shutter tents - it was cheaper to buy another camera than repairing. The Helios 58/2 is still an appreciated lens, sharp also at f/2.
Minolta had Rokkor 58/1.2, Topcor a 58/1.4. If you want one now, there is Voigtländer Nokton...

There have been also a large number of 55/1.2-1.4-1.8, under many brands, some of them by the way very good (the ones supposedly made by Tomioka, a myth among current lens collectors, furthermore likely basing on a Zeiss developed scheme).