resolution question
Moderator: Andreas Wideroe
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zlacza2
resolution question
Does anybody know the approximate resolution of s8 film? I know that 35mm is about 5megapixels, and my guess is that s8 is more than 320x240 but seems to be lower than 640x480, which is DV. Any ideas?
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mattias
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did you honesty think this question had never been asked before or didn't you realize there was a search button near the top of the page? :-)
it's about the same as dv. theoretically a bit higher, about the same as hd, but you'll never get that for various reasons. more importantly, why are you asking?
/matt
it's about the same as dv. theoretically a bit higher, about the same as hd, but you'll never get that for various reasons. more importantly, why are you asking?
/matt
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christoph
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Re: resolution question
oh no, not another flame war ;)zlacza2 wrote:Does anybody know the approximate resolution of s8 film? I know that 35mm is about 5megapixels, and my guess is that s8 is more than 320x240 but seems to be lower than 640x480, which is DV. Any ideas?
please do a search, it has been argued about many many times and there is still no consens.
++ christoph ++
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mattias
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if you do the search you'll see that i've actually tested it. i'm amazed that so few other's have, given the interest i've seen. just shoot a test chart and see for yourselves. the other thing you can do is to look up kodak's specs, but any claims not based on either should just be ignored. especially those involving "an industry professional told me that"... ;-)
/matt
/matt
Article from http://www.extremetech.com/article2/0,15
This is how an article from: http://www.extremetech.com/article2/0,1 ... 635,00.asp sees it.
Digital vs. Film: The Real Low-Down
Which Argument is Right? And Which is Better, Film or Digital?
While it's possible to directly compare a film's grain count with a pixel count, the number would be irrelevant because of the nature of the granules. Pixels have associated bits, called bit depth, that define color and grayscale. In a professional digital camera, each pixel can have anywhere from 36 to 48 bits of data to describe the state of a single pixel. For instance, if a 1x1" CCD has a density of 2000x2000 pixels and a color bit depth of 42 bits, the total number of data bits is 168 million bits, or 21 megabytes.
A single frame of fine grain 1x1.5" 35mm color film has an estimated 13 to 15 million individual silver halide granules. However, film is analog, not digital, so the state of each granule is, theoretically, infinitely variable. The combination of more tightly packed grains and infinite variability in each grain allows film to capture true continuous-tone images, while digital always has a fixed number of steps or grayscale levels limited by the bit-depth of the pixel.
To set the scale of detail, a digital camera's resolution is measured according to the total number of lines it can resolve before they begin to run together. A typical 3 megapixel digital camera has a resolving power of about 1,000 lines over the entire image sensor. So, if the CCD is 1/2" in size, that amounts to a total resolution of 2,000 lines per inch. By contrast, the resolution of fine grain 35mm Kodachrome film is about 2,200 lines--per millimeter! That's more than 50 times better raw resolution than digital. Using this for comparison, film scientists sometimes peg Kodachrome's digital equivalent as a 100 megabyte file. Of course, larger film--2 1/4x 31/4, 4x5", etc.--will yield correspondingly more data and overall resolution than a 35mm frame.
In real life, however, the resolving powers of those respective technologies are actually much closer than the numbers would indicate. That is because of differences in gamuts, or the range of data capable of being represented and reproduced by various input and output devices such as image sensors, film, printers, and monitors. The gamut on film is much higher than digital, but they both come up against a seemingly inexorable bottleneck: the output device's gamut. For film, that's how many lines photographic paper is capable of resolving, and for pixels, it's the number of lines that can be reproduced by an ink jet printer or computer monitor. Both paper technologies are similar in terms of clay coating, brightness and opacity--and gamut. The net result is that with all the extra resolution film captures, it will produce about the same amount of detail in print as is captured by an image sensor. The only way you can make use of film's much greater resolution is either by enlargement--a 35mm frame can be blown up to 14x17" or even 16x20" without an appreciable loss of quality--or viewing it via transmitted rather than reflected light, as with a slide projector.
Tonality is also a tossup, since analog film can, by its very nature, produce greater tonality, while some digital technology, by design and engineering, can capture an appreciably higher dynamic range.
Because the photosensitivity of each granule is set according to its chemical composition and size, it has limits on how much light it can register and absorb. Too little light, and no photochemical reaction takes place. Too much light, and the photons overwhelm the granule and blow it out to a uniform monochromatic black (which, upon reversal, turns all white). The range of normal sensitivity of light to dark is called a film's dynamic range, and it is expressed, not in decibels like an image sensor, but as a logarithm of those decibels, on a scale of 0-5. A medium grain film averages a dynamic range of about 4.0, depending upon the brand and emulsion. That translates into about 6-7 f-stops on a camera lens. Anything above or below is expressed as monochromatic black or white, with no detail whatever.
[ My note: the Zone system and techniques such as pre-flash can shift / increase this range for film ]
Some digital camera image sensors are capable of capturing significantly more detail than film in the highlights and shadows. [For a more detailed explanation, see "Anatomy of a Digital Camera: Image Sensors.] A typical high end image sensor, such as the Philips 2x2K CCD found in many professional camera backs, can capture 11 or more stops of data, roughly double that of a comparable film stock. But again, the extra dynamic range is useful only if the gamma of the output technology allows it to be accurately reproduced.
There are other technical differences that translate into digital or film superiority, such as color fidelity, saturation, etc. But at the end of the day, a good professional photographer can get comparable quality from either technology. And yes, it's entirely possible to use a digital camera to produce images that can be output as Ansel Adams-like museum-quality prints.
Digital vs. Film: The Real Low-Down
Which Argument is Right? And Which is Better, Film or Digital?
While it's possible to directly compare a film's grain count with a pixel count, the number would be irrelevant because of the nature of the granules. Pixels have associated bits, called bit depth, that define color and grayscale. In a professional digital camera, each pixel can have anywhere from 36 to 48 bits of data to describe the state of a single pixel. For instance, if a 1x1" CCD has a density of 2000x2000 pixels and a color bit depth of 42 bits, the total number of data bits is 168 million bits, or 21 megabytes.
A single frame of fine grain 1x1.5" 35mm color film has an estimated 13 to 15 million individual silver halide granules. However, film is analog, not digital, so the state of each granule is, theoretically, infinitely variable. The combination of more tightly packed grains and infinite variability in each grain allows film to capture true continuous-tone images, while digital always has a fixed number of steps or grayscale levels limited by the bit-depth of the pixel.
To set the scale of detail, a digital camera's resolution is measured according to the total number of lines it can resolve before they begin to run together. A typical 3 megapixel digital camera has a resolving power of about 1,000 lines over the entire image sensor. So, if the CCD is 1/2" in size, that amounts to a total resolution of 2,000 lines per inch. By contrast, the resolution of fine grain 35mm Kodachrome film is about 2,200 lines--per millimeter! That's more than 50 times better raw resolution than digital. Using this for comparison, film scientists sometimes peg Kodachrome's digital equivalent as a 100 megabyte file. Of course, larger film--2 1/4x 31/4, 4x5", etc.--will yield correspondingly more data and overall resolution than a 35mm frame.
In real life, however, the resolving powers of those respective technologies are actually much closer than the numbers would indicate. That is because of differences in gamuts, or the range of data capable of being represented and reproduced by various input and output devices such as image sensors, film, printers, and monitors. The gamut on film is much higher than digital, but they both come up against a seemingly inexorable bottleneck: the output device's gamut. For film, that's how many lines photographic paper is capable of resolving, and for pixels, it's the number of lines that can be reproduced by an ink jet printer or computer monitor. Both paper technologies are similar in terms of clay coating, brightness and opacity--and gamut. The net result is that with all the extra resolution film captures, it will produce about the same amount of detail in print as is captured by an image sensor. The only way you can make use of film's much greater resolution is either by enlargement--a 35mm frame can be blown up to 14x17" or even 16x20" without an appreciable loss of quality--or viewing it via transmitted rather than reflected light, as with a slide projector.
Tonality is also a tossup, since analog film can, by its very nature, produce greater tonality, while some digital technology, by design and engineering, can capture an appreciably higher dynamic range.
Because the photosensitivity of each granule is set according to its chemical composition and size, it has limits on how much light it can register and absorb. Too little light, and no photochemical reaction takes place. Too much light, and the photons overwhelm the granule and blow it out to a uniform monochromatic black (which, upon reversal, turns all white). The range of normal sensitivity of light to dark is called a film's dynamic range, and it is expressed, not in decibels like an image sensor, but as a logarithm of those decibels, on a scale of 0-5. A medium grain film averages a dynamic range of about 4.0, depending upon the brand and emulsion. That translates into about 6-7 f-stops on a camera lens. Anything above or below is expressed as monochromatic black or white, with no detail whatever.
[ My note: the Zone system and techniques such as pre-flash can shift / increase this range for film ]
Some digital camera image sensors are capable of capturing significantly more detail than film in the highlights and shadows. [For a more detailed explanation, see "Anatomy of a Digital Camera: Image Sensors.] A typical high end image sensor, such as the Philips 2x2K CCD found in many professional camera backs, can capture 11 or more stops of data, roughly double that of a comparable film stock. But again, the extra dynamic range is useful only if the gamma of the output technology allows it to be accurately reproduced.
There are other technical differences that translate into digital or film superiority, such as color fidelity, saturation, etc. But at the end of the day, a good professional photographer can get comparable quality from either technology. And yes, it's entirely possible to use a digital camera to produce images that can be output as Ansel Adams-like museum-quality prints.
according to the vice prex at tapehouse.com a frame of 35mm has about 15 megs of info. im sure a certain person whos tested film and bitched about people not using the search feature (wich doesnt bother me at all) will complain. all i can say is one of the best telecine houses in the world probably knows more than the rest of us put together.
as for s8 resolution, its a hard thing to calculate but in theory a minimum of 200 line per mm is acheivable with 200t in super8. that gets improved via a widegate ssuper8 conversion and improved further if you use 100t
as for s8 resolution, its a hard thing to calculate but in theory a minimum of 200 line per mm is acheivable with 200t in super8. that gets improved via a widegate ssuper8 conversion and improved further if you use 100t
double super8!
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mattias
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the vice prex? you gotta be kidding me...francis wrote:according to the vice prex at tapehouse.com a frame of 35mm has about 15 megs of info.
why would i, and when have i bitched? i think suggesting the use of the search fearure is being helpful. this *has*, contrary to popular belief, been discussed before and if you're at all interested in getting answers the search buttong is the best starting point i can think of.im sure a certain person whos tested film and bitched about people not using the search feature (wich doesnt bother me at all) will complain.
we already knew you're not a very smart guy, but come on...all i can say is one of the best telecine houses in the world probably knows more than the rest of us put together.
no it's not. you have all the numbers and if in doubt you can just shoot a test chart. i don't understand what it is about that that upsets you so much. you're repeating info already posted in the thread and then you complain about what other's have been saying? i don't get it.as for s8 resolution, its a hard thing to calculate
/matt
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christoph
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15MB means about 5million pixels (which would mean somewhere between a 2K and a 4K scan).. now the super8 frame is about 15times smaller, ie 300K pixels - which is less than DV PAL (at 414K)francis wrote:according to the vice prex at tapehouse.com a frame of 35mm has about 15 megs of info.
somehow i doubt that this is what you wanted to prove though ;)
++ christoph ++
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mattias
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or even less in a 10, 12 or even 16 bit system, which you need to capture all the depth of film. but hey, he's the vice. though somehow i think francis failed to realize that you need a certain level of understanding to understand, even if you're getting the correct info. the way he uses megs and lines in a very non stringent and even confused way shows how much he should be payed attention to.christoph wrote:15MB means about 5million pixels
/matt
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studiocarter
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monobath
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I don't know much about this subject, so I won't express any sort of authoritative opinion. My non-authoritative opinion (admittedly not worth much) is that film still has the ability to capture more information than any currently marketed professional digitial camera. Having said that, I realize I can't prove it, and so I won't take offense if anyone castigates me for speaking out of turn.
As for resolving power of film, I don't believe there are any besides high contrast document films that are close to 200 lpmm. Changing the gate size has no effect on the resolving power of film.
I found this short article interesting.
As for resolving power of film, I don't believe there are any besides high contrast document films that are close to 200 lpmm. Changing the gate size has no effect on the resolving power of film.
I found this short article interesting.
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mattias
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given the same sensor size you're probably right, but surely you don't need proof to realize that a large format digital back will capture a lot more information than a frame of super 8?monobath wrote:My non-authoritative opinion (admittedly not worth much) is that film still has the ability to capture more information than any currently marketed professional digitial camera.
/matt