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Thread: film vs digital

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    film vs digital

    So I have seen this debate continue over the last several years, so here I go.
    One is film and one is digital.
    no fair looking at the metadata





    No special pains were taken in processing either file other than basic conversion and scanning.
    -bob

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    Re: film vs digital

    The top seems more film like ...imo What cameras were used?

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    Re: film vs digital

    Bob, who's starring....I mean looking at the metadata

    All I can say is when I view both these images on a monitor, I much prefer the 1st image. More natural (at least it appears that way), with a smoother rendition in terms of overall look, including aspects of sharpening. Lovely image by the way!

    Dave (D&A)

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    Re: film vs digital

    On my iPad screen, they're impossible to tell apart.
    Reserve judgement until I get back to my desktop system.

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    Re: film vs digital

    But without know the format of the film (and that is a big but), I would say the top is film.

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    Senior Member darr's Avatar
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    Re: film vs digital

    Aren't they all technically digital once you scan the film?
    "Creativity takes courage." ~ Henri Matisse
    Darlene Almeda, photoscapes.com
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    Re: film vs digital

    Quote Originally Posted by darr View Post
    Aren't they all technically digital once you scan the film?
    or when they are sent over the internet?
    Actually I can make the argument that film is digital too at the silver halide crystal level.
    -bob

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    Senior Member darr's Avatar
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    Re: film vs digital

    I think the top one is film based. Film to my eyes gives just a very small tad of diffusion from the plastic base.
    "Creativity takes courage." ~ Henri Matisse
    Darlene Almeda, photoscapes.com

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    Re: film vs digital

    i prefer the tonality on the bottom in numero uno

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    Re: film vs digital

    ok, enough I guess.
    The top image was taken with a D800,
    The bottom, a Hasselblad on Delta 400
    Both were filtered with an orange filter since the lipstick was green and to even-out the skin tones. The D800 by a boost to red and yellow at B&W conversion with C1, the film with a #16 filter.
    The D800 was exposed to the right, the Hassy had a full stop more exposure above filter compensation based on spot-metering the off-blacks.
    Down-sizing on the D800 file was done by c1, the film was scanned then processed in Photoshop to down rez and adjust the blacks. I should perhaps have clipped the whites a bit to get better catch-lights in the eyes, but I just forgot.
    100% crops from each are below.
    Attachment 68830

    Attachment 68831
    -bob

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    Re: film vs digital

    The point made that both have become digital after scanning has some merit. And Bob's point that we are looking at them digitally via the computer is even more so.

    The only way to actually compare film to digital is to develop the film and print the picture. Then take the digital image and print with an inkjet printer. In order to make a comparison, both images should be placed under the exact same light and judged then.

    In Hawaii last month, i viewed Peter Lik photos, and they looked so good that they seemed backlit. Later I looked at the same images on the computer, and they didn't even look like the same picture. His studio evidently lights each image with such precision that they are presented perfectly (and not realistic when it comes down to it) so when hung in the home they must look disappointing.

    In the Cowboy Museum in Oklahoma City, OK, many years ago, I saw my first Ansel Adams prints, done by him, that actually blew me away. Wow, I have never seen BW prints to come close to those since. I can say without hesitation that I do not believe digital will ever come close to those images.

    But I do appreciate Bob doing this exercise, because it was interesting to see all who dared to compare got it wrong. I didn't have the nerve to express an opinion so my hat is off to those who did.

    Greg
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    Re: film vs digital

    Quote Originally Posted by Godfrey View Post
    On my iPad screen, they're impossible to tell apart.
    Reserve judgement until I get back to my desktop system.
    At my desk now.

    Viewing the two samples you've presented on my calibrated desktop display, I'd say that anyone sneering at differences in quality between film and digital capture at this level has their head stuck up where the moon don't shine. To tell them apart is a microscopic journey into irrelevancy.

    G

    Photographers should spend more time worrying about quality images and less time nattering on about image quality.

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    Re: film vs digital

    I guessed correctly, though I readily admit that it was a guess.

    I noticed that in the bottom image the hip of the model is more grainy, especially in the shadow region of the navel. At that point I guessed that the bottom image was film, but then considered that Bob may have added grain to the digital image in order to throw people. When I read that Bob had not processed the images I committed to my original opinion.

    For what it's worth, I prefer the first, digitally captured, image. The skin of the model is significantly smoother than it is in the bottom image.
    Rob
    www.robbuckle.co.uk
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    Re: film vs digital

    Quote Originally Posted by AreBee View Post
    I guessed correctly, though I readily admit that it was a guess.

    I noticed that in the bottom image the hip of the model is more grainy, especially in the shadow region of the navel. At that point I guessed that the bottom image was film, but then considered that Bob may have added grain to the digital image in order to throw people. When I read that Bob had not processed the images I committed to my original opinion.

    For what it's worth, I prefer the first, digitally captured, image. The skin of the model is significantly smoother than it is in the bottom image.
    With regards to what you expressed, thats why in my inital response "above", I simply stated which of the two images I preferred, which was the 1st one, without considering whether it was initially captured digitally or on film.

    As expressed by others, the process by which we scan film already digitizes it, so it's hard to access at that point the absolute differences and merrits of both with regards to the purity of each type of media capture utilized.

    The idea suggested that each capture should directly be outputted to print and compared is a good one. I'd even take it a step further and add a 3rd print....which would be the film image scanned and then printed, to see what if anything is gained or lost from the film image printed by conventional means in the wet darkroom. I'd love to see all three of these prints!

    Interesting comparison Bob...thanks!

    Dave (D&A)

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    Re: film vs digital

    I had an opinion pretty much straight away, and it was the smoothness that gave it away- digital takes away all the flaws sometimes, it is like a screening process, and skin is just never that even and smooth. Also hair looks completely different in film vs. digital, in digital it is softer and more regular.
    I think the problem with digital is the perfection problem, there is no baseline, we all start perfecting the image once it is captured, and soon, all the life is drained away. Film tends to preserve and foreground the flaws, and in this aspect, it keeps the "art" alive. Just my opinion.
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    Re: film vs digital

    Looking at the crops, I do see the differences now, but from the original print, as is, with no peeping, I was wrong...no butts about it

    What it also shows, is that 35mm dslr(D800) can hold up quite well to MF.

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    Re: film vs digital

    Quote Originally Posted by johnnygoesdigital View Post
    What it also shows, is that 35mm dslr(D800) can hold up quite well to MF.
    Yes, it can and often quite well....but there are times when viewing similar images taken with a D800 and 40MP camera, primarily in larger prints, that differences between the two is evident. It depends of course on so many factors.

    Dave (D&A)

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    Re: film vs digital

    Quote Originally Posted by BANKER1 View Post
    In the Cowboy Museum in Oklahoma City, OK, many years ago, I saw my first Ansel Adams prints, done by him, that actually blew me away. Wow, I have never seen BW prints to come close to those since. I can say without hesitation that I do not believe digital will ever come close to those images.
    I agree 1000%


    Quote Originally Posted by BANKER1 View Post
    But I do appreciate Bob doing this exercise, because it was interesting to see all who dared to compare got it wrong. I didn't have the nerve to express an opinion so my hat is off to those who did.
    I try not to play these kinds of "gotcha" games anymore. Digital and film are classes, not particulars. Attempts to form judgments about broad groups based solely on comparisons of extremely similar individuals will always be prone to error. It might be a fun exercise and a way to trick people, but it's not really a fair exercise at all when it comes to seriously judging the differences between film and digital.

    For those that are interested, some of the best thought I've ever encountered on this subject was written by Nelson Goodman in his chapter on art forgeries in "Languages of Art."

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    Re: film vs digital

    I happen to have an Ansel Adams print purchased from him directly in the 1960s.
    I use it for reference.
    Mostly I would say that I can come almost as close as I want to those as far as print quality is concerned. The biggest issue is getting a DMax close enough to Silver Bromide so that under identical lighting conditions the reflectance range can be matched. Of course, there is the issue of selenium toning which imparts a rather rich color to the blacks which can be mimicked in PS but it depends a bit on the ink-set used.
    I would have said it was "pretty close" with Harman FB AL, but that surface is distracting. Exhibition Fiber is perhaps the closest I have seen.
    Of course I am viewing both prints in a lighting booth so it is a fair comparison.
    I would say also that when we shoot digital, and expose to the right, that in those cases where the camera's DR is bigger than the subject, we tend to be placing blacks on the straight-line part of the curve. Zone System processing very carefully exposes for the blacks (or near blacks) and then adjusts the curve to get the beginnings of gentle roll-off in the highlights.
    When processing digital to get the best film-mimic look, I would say that exposure is very important, and that exposing a bit less that ETTR would imply is necessary, perhaps 1/3-2/3 stop but no less.
    Digital gets into trouble mostly because it is very hard to do the equivalent to N-1 processing without losing something. N+1 is easy.
    -bob

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    Re: film vs digital

    Quote Originally Posted by Bob View Post
    I happen to have an Ansel Adams print purchased from him directly in the 1960s.
    I use it for reference.
    very cool

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    Re: film vs digital

    Quote Originally Posted by Bob View Post
    I happen to have an Ansel Adams print purchased from him directly in the 1960s.
    I use it for reference.
    Mostly I would say that I can come almost as close as I want to those as far as print quality is concerned. The biggest issue is getting a DMax close enough to Silver Bromide so that under identical lighting conditions the reflectance range can be matched. Of course, there is the issue of selenium toning which imparts a rather rich color to the blacks which can be mimicked in PS but it depends a bit on the ink-set used.
    I would have said it was "pretty close" with Harman FB AL, but that surface is distracting. Exhibition Fiber is perhaps the closest I have seen.
    Of course I am viewing both prints in a lighting booth so it is a fair comparison.
    I would say also that when we shoot digital, and expose to the right, that in those cases where the camera's DR is bigger than the subject, we tend to be placing blacks on the straight-line part of the curve. Zone System processing very carefully exposes for the blacks (or near blacks) and then adjusts the curve to get the beginnings of gentle roll-off in the highlights.
    When processing digital to get the best film-mimic look, I would say that exposure is very important, and that exposing a bit less that ETTR would imply is necessary, perhaps 1/3-2/3 stop but no less.
    Digital gets into trouble mostly because it is very hard to do the equivalent to N-1 processing without losing something. N+1 is easy.
    -bob
    Interesting observations and valuable thoughts Bob!

    Dave (D&A)

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    Re: film vs digital

    You're just comparing two digital images, to no obvious purpose.

    Once an image is digitized it is by definition a digital image, regardless of how it started.

    The only valid comparison of technologies would be to put a digital print on a wall next to a real film/wet lab print and compare them under identical lighting conditions.

    The obvious difference in the technologies is that film/wet lab prints can capture an infinite number of gray tones; digital modes cannot.

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    You're just comparing two digital images, to no obvious purpose.

    Once an image is digitized it is by definition a digital image, regardless of how it started.

    The only valid comparison of technologies would be to put a digital print on a wall next to a real film/wet lab print and compare them under identical lighting conditions.

    The obvious difference in the technologies is that film/wet lab prints can capture an infinite number of gray tones; digital modes cannot.

    - Leigh
    Exactly what I thought (and stated) but if you provide the digital file and negative to 10 different individuals to print each via ink jet and wet darkroom respectfully, the results will be considerably different with each pairing. Having each use the same papers, printers, chemicals and so forth, will narrow down these differences to a degree. A while back I partook in both judging and participating in such an exercise and the results were quite revealing, to say the least.

    It's now come down to different mediums, where each is quite capable of achieving remarkable results but where output to print reveals strinking differences. Unfortunately web sized images tends to equalize a great many things.

    Dave (D&A)

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    Re: film vs digital

    In both photos she has a top but no bottoms.
    Brad Husick

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    Re: film vs digital

    Quote Originally Posted by D&A View Post
    A while back I partook in both judging and participating in such an exercise and the results were quite revealing, to say the least.
    So what were the results of that comparison?

    There certainly is a wide range of results attainable from either technology.

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by bradhusick View Post
    In both photos she has a top but no bottoms.
    I see two perfect bottoms
    Remember: adventure before dementia!

    As Oscar Wilde said, "my tastes are simple, I only like the best"

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    Re: film vs digital

    Actually, I have, and infinite is well beyond what you can see and besides not what that technology will yield given the quantization of exposed silver halide crystals. Rather it is a dithering result that you see, softened by diffusion of enclosing gelatin. At RIT, it seems like a hundred years ago, we tried to figure out how many "bits equivalent" in digital terms we have with film. It turns out that is is somewhere between 12-14.
    I will agree that if the print is examined under a loupe, you will see two different dithers. Digital printers tend to dither in a regular array, digital prints tend to lay down a pseudo-random dither with rather less sharp dots.
    -bob


    Quote Originally Posted by Leigh View Post
    You're just comparing two digital images, to no obvious purpose.

    Once an image is digitized it is by definition a digital image, regardless of how it started.

    The only valid comparison of technologies would be to put a digital print on a wall next to a real film/wet lab print and compare them under identical lighting conditions.

    The obvious difference in the technologies is that film/wet lab prints can capture an infinite number of gray tones; digital modes cannot.

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    So what were the results of that comparison?

    There certainly is a wide range of results attainable from either technology.

    - Leigh
    Your statement reflects the essence of what was observed. In one instance (test) where each participant was allowed free range of choice of papers, film, chemicals, but the ink jet printer, enlarger w/lens was kept constant as was the lens used on both the film based and DSLR camera, each matched pair of prints were fairly divergent in their look and the consensus was the conventional wet print was far more impressive in terms of dynamic range and gradations in tonal transitions among many other attributes. Most favored was the darkroom/film generated print.

    In instances where we tried matching as closely as possible the use of papers in both technologies...various Baryta ink jet papers were employed with the digital generated file, while fiber or RC Variable contrast papers were used in the darkroom. Both types are commonly used in these sorts of comparisons. Film type and developers (for film and papers) were kept constant as were other components outlined in 1st test (above).

    The results were closer this time around, but differences were still obvious, especially for those who knew what to look for. Reproduction of blacks were "still" different as was the perceived detail in textual components. Of course this could be somewhat manipulated in post processing with the digital file. Some of the differences I previously outlined in the 1st test were also evident. As for those examining each pair of prints, the feeling was it was often subject dependent which technology was preferred. Industrial and landscape type images were often preferable in the digital realm while portraits were more evenly split between the two technologies with most leaning towards the film/wet darkroom generated print. I was surprised about the landscape results, expecting more favoring conventional film and print.

    What I presented here of course is an over simplification of the results and opinions of the participants and a very lively discussion took place as to the merits and strengths of each process. I'm not sure there was a clear cut winner, nor did most others who participated.

    Dave (D&A)
    Last edited by D&A; 4th February 2013 at 17:33.

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    Re: film vs digital

    If I am printing a 3' x 16' panorama, I would not want to do that optically in a wet darkroom.

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    Re: film vs digital

    Thanks, Dave. That's pretty much what I expected.

    It's awfully difficult to separate preconceptions from actual observations in such a test.

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by Bob View Post
    It turns out that is is somewhere between 12-14
    I'm sorry, Bob, but that suggests flawed methodology.

    12 bits is only 4096 gray levels. That can easily be disproved by examination.

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    12 bits is only 4096 gray levels. That can easily be disproved by examination.
    Well, since you only need about 200 levels of gray to create a visually stepless gradient from black to white, I would say you could never see a 12 bit gradient as anything but stepless.

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    I'm sorry, Bob, but that suggests flawed methodology.

    12 bits is only 4096 gray levels. That can easily be disproved by examination.

    - Leigh
    Actually this is a trick question...
    Ok, how would you examine it?
    How many silver halide crystals are there per square micron?
    Fine grain films have a crystal size that is approximately one micron in diameter. Each crystal is actually a binary sensor. It is either exposed enough to reach its threshold to develop, but when it does it is developed completely. There is no grey, only black or white. If course these grains often do not cover 100% of the area but occasionally can approach 100% coverage. Lets say they do, and lets say we take a sample of 10 microns on a side. That sample will only contain roughly 100 crystals and can have only 100 different levels of transmission.
    So actually, depending on the subtended area, the levels possible to be represented by silver halide emulsions is limited by the number of grains that exist in the sample.
    -bob

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    Re: film vs digital

    Quote Originally Posted by Shashin View Post
    Well, since you only need about 200 levels of gray to create a visually stepless gradient from black to white, I would say you could never see a 12 bit gradient as anything but stepless.
    So the reason for using 16 bits or more for gray scale and 48 bits or more for RGB is what?

    Those standards place a significant burden on storage and processing power.
    You would have us believe that no benefit is derived from that???

    - Leigh

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    Re: film vs digital

    Bob, don't forget covering power also plays into that equation. I am sure that is an M&P question.

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    So the reason for using 16 bits or more for gray scale and 48 bits or more for RGB is what?

    Those standards place a significant burden on storage and processing power.
    You would have us believe that no benefit is derived from that???

    - Leigh
    Processing and data. Both valid. But visual perception of an image is something else, I only need 200 levels to create the illusion.

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    Re: film vs digital

    Quote Originally Posted by Shashin View Post
    There is no grey, only black or white. If course these grains often do not cover 100% of the area but occasionally can approach 100% coverage. Lets say they do, and lets say we take a sample of 10 microns on a side. That sample will only contain roughly 100 crystals and can have only 100 different levels of transmission.
    Invalid assumptions.

    You're neglecting the depth of the emulsion and the orientation of the grains.
    Both factors can dramatically increases the number of possibilities.

    I went through an exhaustive study of this effect on a product that I designed a few years ago.
    It counted microscopic particles in a fluid, which flowed through a sensor array.

    The methodology was quite simple for low densities of particles, but became much more complex when the concentration exceeded about 10% of the presumed maximum, which itself was not nearly full saturation.

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    So the reason for using 16 bits or more for gray scale and 48 bits or more for RGB is what?

    Those standards place a significant burden on storage and processing power.
    You would have us believe that no benefit is derived from that???

    - Leigh
    16 bit units are so much easier to use than 12 or 14. Most digital sensors barely get much beyond noise in the 13th or 14th bit.
    Folks like "malleable" files that can be pushed or pulled a bit. Each stop of push uses one of those bits. In the darks, when most of the most significant bits are zero anyway, you are left with precious few bits of actual information.
    IMO 16 bits is a nice tradeoff of space vs processing requirements.
    To extract 14 bits say from a contiguously encoded format requires for most machines a load, a variable length shift and and "and" operation to mask the extraneous bits.
    -bob

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    Invalid assumptions.

    You're neglecting the depth of the emulsion and the orientation of the grains.
    Both factors can dramatically increases the number of possibilities.

    I went through an exhaustive study of this effect on a product that I designed a few years ago.
    It counted microscopic particles in a fluid, which flowed through a sensor array.

    The methodology was quite simple for low densities of particles, but became much more complex when the concentration exceeded about 10% of the presumed maximum, which itself was not nearly full saturation.

    - Leigh
    I counted crystal grains in dry photographic emulsions. Only rarely did we find dried films that had significantly overlapping crystals although we did find some that had almost complete coverage.
    Here is a link to some electron microscope images of a few representative films http://www.optics.rochester.edu/work.../spr04/jidong/
    Of course, if the film area considered is large enough and there is a potential, say for detection of even one grain more or less, then given a large enough sample of film, an arbitrarily large number of "levels" might be encoded.
    -bob

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    Re: film vs digital

    Quote Originally Posted by Bob View Post
    I counted crystal grains in dry photographic emulsions. Only rarely did we find dried films that had significantly overlapping crystals although we did find some that had almost complete coverage.
    Here is a link to some electron microscope images of a few representative films Photographic Film
    I'm sorry, Bob, but you did not measure grains "in dry photographic emulsions".

    From the Background Information section on the linked page:
    "Therefore, if we take image directly with the unprocessed photographic film samples, what could be seen is just the situation on the very top of the gelatin/silver halide particle mixture. This means very poor image quality and sparsely distributed silver halide particles, which is of course not desirable. Taken these into account, some special sample preparation is necessary: to remove silver halide particles from film base and then redisperse them on SEM sample stub."

    Since the grains were completely removed from the film, centrifuged, then re-deposited on a sample carrier in an intentionally thin layer, the results do not correlate with measurements taken in situ.

    The methodology quite specifically precludes evaluation of grain overlap in an actual emulsion.


    - Leigh
    Last edited by Leigh; 4th February 2013 at 19:17.

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    Re: film vs digital

    The article in the linked page concludes--->"These results meet the macro-pheomena: Professional film, positive film and low ISO film show smoother grain and vice versa"

    I almost want to say "duh"....one doesn't need electron microscopy to evaluate and come to this conclusion . I think this fact was well established before electron microsopy was even in existance. (I just couldn't resist...LOL!)

    Dave (D&A)

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    Re: film vs digital

    +1 Yup.

    Except I don't know what a pheomena is.

    - Leigh
    Last edited by Leigh; 4th February 2013 at 21:16.

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    Originally Posted by Shashin
    There is no grey, only black or white. If course these grains often do not cover 100% of the area but occasionally can approach 100% coverage. Lets say they do, and lets say we take a sample of 10 microns on a side. That sample will only contain roughly 100 crystals and can have only 100 different levels of transmission.
    Invalid assumptions.

    You're neglecting the depth of the emulsion and the orientation of the grains.
    Both factors can dramatically increases the number of possibilities.

    I went through an exhaustive study of this effect on a product that I designed a few years ago.
    It counted microscopic particles in a fluid, which flowed through a sensor array.

    The methodology was quite simple for low densities of particles, but became much more complex when the concentration exceeded about 10% of the presumed maximum, which itself was not nearly full saturation.

    - Leigh
    I did not post what you are quoting. I am not sure why particles flowing through fluid is very relevant.

    BTW, what is the depth of a standard photographic emulation? I would love to know because the film companies don't publish that data. Most people only know the base thickness which is far greater.

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    Re: film vs digital

    My comments were not directed at you; they were for Bob.

    The distribution of particles in a fluid is absolutely relevant, since that's exactly what you have when an emulsion is coated, before it dries. After it dries, it just freezes the particle distribution.

    I too would like to know the emulsion thickness. I don't have that information.
    You could easily find out by removing the emulsion from half a sheet of film, then measuring the thickness of both areas.

    Also, I'd like the definition of a micron in this context. It's used in various disciplines to mean either one millionth of a metre or one millionth of an inch. Two very different sizes.

    - Leigh

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    Re: film vs digital

    Well, I took this morning. It is a section of color negative film. Emulsion to the bottom. 50x objective with DIC.



    Here is a 10um overlay. I work in SI units and so that is a real micron of one millionth of a meter (0.001mm). The grid is 0.01mm squares. (What is an inch? And who defines a micron in relation to one? Certainly not scope manufacturers--electron or otherwise)



    This is from the developed leader and so I don't know how much swelling is going on--it certainly has an unusual density as it was completely exposed to light. Nor do I know how the cutting machine has deformed the emulsion. Still, with three color layers and an integral mask, it is not very thick--20um or less. I would imagine B&W emulsions are thinner.

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    Re: film vs digital

    Very cool.
    I was furiously looking for data on film emulsion thickness and found only one source for radiographic film which was listed as 10 microns(metric)
    I am guessing that the cross-section you have posted looks roughly like about a 20 micron thickness but we know that color negative film is often coated in at least 4 layers (three color and one usually thinner yellow filter).
    So unless we have more data, can we assume that the emulsion layer is on the order of 5-10 microns? I seem to recall this figure although I have misplaced my old copy of Mees and James.
    Also, can we assume that the emulsion consists of approximately 40% silver halide and 60% binder (from memory)
    I unfortunately predate tabular crustal emulsions which seem to be pretty popular, but it appears to me that these are roughly 1 micron across the base. I do not have a good reference for their thickness.
    The next step might be the estimation of the number of such grains in a volume of emulsion at nominal thickness and some area we might agree as that which effectively is a perceivable unit of area.
    For sake of argument, perhaps we have an enlarging factor of perhaps 2 (approximately a 4x5 negative enlarged to an 8x10 print) to 8 (35mm frame's 24mm enlarged to 8 inches).
    Final print observable minimum feature size of lets say 85 microns (300 per inch converted to SI) which gives us a film "observable unit" from say between 42 microns on a side for 4x5 and 11 on a side for 35mm.
    Anybody have better data for these assumptions?
    thanks
    -bob
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    Re: film vs digital

    The term micron, defined as a millionth of an inch, was used in the machine tool industry at least 100 years before the SEM was invented.

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    The term micron, defined as a millionth of an inch, was used in the machine tool industry at least 100 years before the SEM was invented.

    - Leigh
    Maybe so, but the SI version seems to be the one most used today in photographic and scientific applications.
    -bob

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    Re: film vs digital

    Hi Bob,

    I don't disagree. SI units are certainly common in contemporary scientific usage.

    But back when coating machines were invented, they were built by an industry that used inches, and micro-inches (microns).

    - Leigh

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    Re: film vs digital

    Quote Originally Posted by Leigh View Post
    Hi Bob,

    I don't disagree. SI units are certainly common in contemporary scientific usage.

    But back when coating machines were invented they were built by an industry that used inches, and micro-inches (microns).

    - Leigh
    LOL we were using SI back in 1967 when I used to do this.
    -bob

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