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  1. #1
    T42
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    A Question about the First Leicas

    Hello Forum.

    Seems that I have read someplace that marketing for some early Leicas claimed that they were able to resolve one million picture elements, or some words to that effect.

    I am puzzled trying to discern what that first Leica with a 5cm f3.5 Elmar might equate to if translated into terms of a modern camera's image resolving power. I understand this is an issue of optics and film in the Leica.

    But I am wondering how to figure out about what megapixel count would have been required to deliver the images that the Leica's lens could resolve at that time.

    Or to put it into another, simplistic sort of way... How many megapixels was that first Leica? Any way to know this kind of thing?

    Thanks.

    Henry
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    My first question is what are you trying to "prove"?

    The question is in essence unsolvable. Too many variables. Are you talking at all apertures? With modern or contemporary film? With high or low contrast targets? Are you interested in just resolving power or its MTF? Are you interested in a "look"? How do you "translate" an analog image to a digital one (simply thinking in lines/mm and dividing a sensor into an imaginary grid does not tell the whole story)? Are you looking to match a sensor to the lens?

    A simple way to get a feel about how this lens works is by mounting it on an M9 (or an m4/3 or Sony Nex camera and extrapolate an answer for a 35mm-size image plane).

    BTW, in modern terms in purely technical quality, the 5cm Elmar is not such a great lens.

  3. #3

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    Hi

    As previous post, MTF for the early Elmar are available, or you can try one with modern mono or color film or even a M9. Lots of people still use them.

    The contemporary film was slow and grainy...

    Even the modern circa 94 Elmar in high refractive glass has a (residual) thin lens triplet signature, but is compact.

    Noel

  4. #4
    AgX
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    Relating image detail of film to pixel-number of digital sensor is a venture, technically speaking.

  5. #5
    Jim Jones's Avatar
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    As others imply, comparing traditional film resolution tests with pixel counts isn't valid. However, tests of a later Elmar http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=003PVO indicate at least 40 line pairs per mm resolution, corner to corner. This might be similar to several mp resolution in a digital camera. Of course center resolution is better. The early Elmar might not fare so well, but could make fine images. That's really the most important consideration.

  6. #6
    ic-racer's Avatar
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    As pointed out that lens has resolution less than typical film. In terms of megapixels, film does not have pixels.

  7. #7
    T42
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    Thanks Fellows.

    I can see now that I should have framed the thread's question differently. I understand that there are many variables involved. Allow me to key in on Hikari's question: "My first question is what are you trying to "prove"?"

    Okay, here is the collection of basic ideas which I have read, and which precipitated the question I am trying to frame and get answered:

    It has been said that Leitz's introduction of the Leica and its subsequent growing popularity changed photography fundamentally. Pictures which were once made by contact prints could thereafter be made by enlargement more effectively than in previous times. This was attributed in part to the Leica's lens being capable of making reasonably sharp images, sharp enough to enlarge a few times at least and still be "perceived" as sharp.

    That gets to Jim Jones' comment: "The early Elmar might not fare so well, but could make fine images. That's really the most important consideration."

    By the early 1930s, the 35 was becoming accepted for journalism and for magazines like National Geographic, LOOK, LIFE, and such. Zeiss Contax was getting into the 35mm game by then too.

    I read in Morgan and Lester's 1956 edition of The Leica Manual and Data Book that the human eye can only see about 1/30th of a degree in terms of resolving what is perceived as "sharp." It also submits that most people see clearly no closer than about ten inches away. This, they say, works out to an ability of the human eye to resolve at most about 100 lines per inch in the finished print, viewed from 10 inches away. From this the authors add that at 20 inches away, that resolution goes down to 50 lines per inch. 25 lines at 40 inches away, and so on. At 2000 inches a brick wall with 2 inch bricks will begin to look like a solid red wall. A billboard seen from a distance "appears" sharp, because we never get close enough to see those dots. All this because of the eye's 1/30th degree limitation to resolve details.

    So, the idea goes, that the maximum size print that one would want to hold at ten inches for examination, and perceive as sharp, defines the basic requirement for resolution in a camera/lens/film combination. A ten inch print would need 1000 lines in the 10 inch dimension.

    Okay, I think I got that. Sorta. But whatever does all that translate to in terms of modern nomenclature such as line pairs and pixels?

    What specification of modern pixel-packing camera would reasonably equate to the Leica of 1925 or 1933 or thereabouts? Assume optics and film then available about 1930.

    My guess is that it would only be a few Mpxls at most, as Jim Jones mentioned upthread. But with all the variables and differences in nomenclature involved like lines, line pairs, dots, pixels, ad infinitum, it is difficult for me to come to any reasonable way of getting an answer by calculation.

    Thanks for trying to help.

    HTH..
    Last edited by T42; 12-26-2010 at 09:31 PM. Click to view previous post history. Reason: dumb typos
    Henry
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  8. #8
    T42
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    Hello Steve.

    It only matters inasmuch as I am trying to understand how over-hyped all the megapixel stuff is with those who think digital is the beginning and the end of photography today. The earliest Leicas, in the hands of real photographers, made pictures good enough for LOOK, LIFE, and National Geographic.

    As we all know here, there are many considerations more important than stupid megapixel counts and the length of "feature" lists.

    BTW, I like your tagline. I used to have a 500c with 80mm Planar. Stupendously good images it made in my hands. I miss it still. And 6cm film is so much more fun to me in the darkroom too. That was the only camera I ever sold and which I regretted selling later on.

    Happy day.

    Henry
    A Certified Dinosaur
    Nikons F, F2, D700, Leica M3, & Kiev 4a

  9. #9
    Jim Jones's Avatar
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    [QUOTE=T42;1111351]I read in Morgan and Lester's 1956 edition of The Leica Manual and Data Book that the human eye can only see about 1/30th of a degree in terms of resolving what is perceived as "sharp." It also submits that most people see clearly no closer than about ten inches away. This, they say, works out to an ability of the human eye to resolve at most about 100 lines per inch in the finished print, viewed from 10 inches away. From this the authors add that at 20 inches away, that resolution goes down to 50 lines per inch. 25 lines at 40 inches away, and so on. At 2000 inches a brick wall with 2 inch bricks will begin to look like a solid red wall. A billboard seen from a distance "appears" sharp, because we never get close enough to see those dots. All this because of the eye's 1/30th degree limitation to resolve details. . [. ./QUOTE]

    I suspect, but haven't tested, the eye's ability to sense much finer detail than scientists claim. It takes a lot of halftone dots per inch to make a reproduction that feels much like the original photograph. Of course other factors than resolution are involved in such a comparison. If the 1/30 degree resolution cited above is absolutely valid, there would be less need for LF contact prints.

  10. #10
    T42
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    Hello Jim.

    I appreciate your help.

    I suspect, but haven't tested, the eye's ability to sense much finer detail than scientists claim. It takes a lot of halftone dots per inch to make a reproduction that feels much like the original photograph. Of course other factors than resolution are involved in such a comparison. If the 1/30 degree resolution cited above is absolutely valid, there would be less need for LF contact prints.
    Good point about LF contacts. Morgan and Lester may not be right. I can't prove what those two Leicaphiles said about 1/30th degree, nor do I see it mentioned elsewhere on the web yet. I agree with the gentlemen above who suggest that there's definitely more to this than a simple digi/film comparison.

    I note that up-thread you wondered if the early Elmar might have had about 40 line pairs per millimeter. That would translate to about 80 pixels per mm. So, then, (24mm X 80 pixels) times (36mm X 80 pixels) would suggest a capability of the camera in the neighborhood of 5.5 Mpxls ... if the film then available could resolve it also, and if all those other variables were not overbearing.

    If so, I am left thinking that it might be that the early Leicas which were thought to be "sharp enough" and "enlargeable enough" to enter the service of National Geographic, LOOK, and LIFE, just might have been capable of what we now think of as 5 or so megapixels.

    Consider Lester and Morgan's idea about 100 lines per inch in the finished print, viewed at no closer than ten inches. At 40 lines per mm in the negative, that implies potential for a 14.4 inch print in the long dimension, and which would be "perceived as sharp" when viewed at ten inches away. I think I would probably view a 14 inch print further away than that. I will guess that is about as large as an image would have appeared in LOOK, National Geographic, or LIFE.

    I'm assuming that the "line" of 1956 is the "line pair" of today, and that a line pair is approximately the same as 2 pixels. The "lines" described by Lester and Morgan have white spaces between them, but they do not use the term "line pair" as we do today.
    Last edited by T42; 12-28-2010 at 12:32 AM. Click to view previous post history. Reason: typo
    Henry
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    Nikons F, F2, D700, Leica M3, & Kiev 4a

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