Routine negative film has a resolution of about 5000 linear dots per inch. That means that a shot on 35mm film contains about 33.5 megapixels of data. Since the original post talks about medium format film, we have to consider negatives up to 6x9 centimeters (6.25 times the size of a 35mm frame or the sensor in a 'full frame' digital camera). That's about 209 megapixels of data.
There are subtleties here involving the resolution needed to capture individual gains in high contrast regions of film, and you might if you were being extremely conservative cut these numbers in half. That would take you to about 16.75 megapixels for a good 35mm camera, and 105 megapixels for medium format.
"... we have to consider negatives up to 6x9 centimeters ... That's about 209 megapixels of data."
From what I heard, medium format lenses were never that good. Picture was large but nothing more: they were not very sharp. IOW "209MP" is exaggeration.
At such resolutions, optics becomes the bottleneck. Even if you cover 6x9 area but optical resolution is low, you would get "209MP" which can be converted to say 30MP without loss of information.
Considering that modern optics for digital cameras drastically increased resolution - they are sharper than what was used in film times - I think your math behind both "33.5MP" and "209MP" is wrong.
More film resolution != more image information.
More film resolution + more optical resolution == more image information.
I hope you understand that "lens" is not the same as "piece of glass". Even prime lenses have very complicated light path and have to utilize all possible kinds of innovations (low dispersion glass, super low dispersion glass, aspherical elements, etc) to maintain high resolution. Most of this stuff wasn't even available until very recently.
I was factoring in the scanner mentioned- Nikon Coolscan 9000, which has a resolution of 4000 dpi. Over the area of a 6x9 negative I got 106 megapixels. The film could have an infinite resolution- the scan is still the limiting factor.
I have found my Mamiya's lenses to be as good as any. My Mamiya 6 is just like a big Leica.
Should I even rebut somebody who starts his post with "From what I heard..."? It is ironic you simultaneously advertise your ignorance and attempt to lecture others. However, for the sake of other readers, I will respond to your claim that "modern optics for digital cameras drastically increased resolution". This is wrong. The best optics for digital cameras are identical to the best optics for film cameras. Literally identical, you can detach the lens from a digital SLR, attach it to a film camera with the same mount, and resume taking pictures.
"From what I heard, medium format lenses were never that good." No, there exist high quality lenses for medium format cameras, just as there exist high quality lenses for large format cameras, 35mm cameras, and even APS cameras. Even if you get a bit of distortion or chromatic aberration in one of the larger format lenses, increasing your image size by a factor of 6.25 (for medium format) or 15 (for large format) is such a massive improvement that everything else gets lost in the decimal places.
The computation of 110megapixels for a 6x9 negative is correct, even conservative. With higher speed films and some slide emulsions, you will see grain at this resolution, but the people using this sort of equipment will often value the grain and anyway can remove it after scanning if they want to.
The availability of high quality 100+ megapixel images from 30 year old cameras with modern scanners is part of the reason why medium format digital cameras exist, in order to compete. Such cameras have resolutions running from about 50 megapixels to about 150 megapixels.
One might reasonably raise the question of whether any normal user needs resolution above 8 megapixels or so. Certainly one can get excellent images at 4x6 without going higher. But to extrapolate that film is not capable of higher resolution would not be correct.
None of this refers to Leicas, of course. They make nice cameras, but for $9000 what you are mostly buying is a status symbol.
And as for this comment --
"I hope you understand that "lens" is not the same as "piece of glass"."
@stern: "Should I even rebut somebody who starts his post with "From what I heard..."? It is ironic you simultaneously advertise your ignorance and attempt to lecture others."
Well, I wonder who's ignorant. At least I have openly stated that's not my own experience.
"The computation of 110megapixels for a 6x9 negative is correct, even conservative. With higher speed films and some slide emulsions, you will see grain at this resolution, but the people using this sort of equipment will often value the grain and anyway can remove it after scanning if they want to."
I was talking about actual amount of information in the final image - not about scans. And the fact that as you mention grain becomes visible clearly points that you go far above the resolution limit.
Using your logic I can print picture from 10MP E-520 on A1, scan it at high DPI and claim that even my E-520 can produce images of ZOMG gazillionsMP.
Now that we've thrown 'em off the trail, use the form below to get in touch with the people at Engadget. Please fill in all of the required fields because they're required.
Routine negative film has a resolution of about 5000 linear dots per inch. That means that a shot on 35mm film contains about 33.5 megapixels of data. Since the original post talks about medium format film, we have to consider negatives up to 6x9 centimeters (6.25 times the size of a 35mm frame or the sensor in a 'full frame' digital camera). That's about 209 megapixels of data.
There are subtleties here involving the resolution needed to capture individual gains in high contrast regions of film, and you might if you were being extremely conservative cut these numbers in half. That would take you to about 16.75 megapixels for a good 35mm camera, and 105 megapixels for medium format.
Cheers.
"... we have to consider negatives up to 6x9 centimeters ... That's about 209 megapixels of data."
From what I heard, medium format lenses were never that good. Picture was large but nothing more: they were not very sharp. IOW "209MP" is exaggeration.
At such resolutions, optics becomes the bottleneck. Even if you cover 6x9 area but optical resolution is low, you would get "209MP" which can be converted to say 30MP without loss of information.
Considering that modern optics for digital cameras drastically increased resolution - they are sharper than what was used in film times - I think your math behind both "33.5MP" and "209MP" is wrong.
More film resolution != more image information.
More film resolution + more optical resolution == more image information.
I hope you understand that "lens" is not the same as "piece of glass". Even prime lenses have very complicated light path and have to utilize all possible kinds of innovations (low dispersion glass, super low dispersion glass, aspherical elements, etc) to maintain high resolution. Most of this stuff wasn't even available until very recently.
I was factoring in the scanner mentioned- Nikon Coolscan 9000, which has a resolution of 4000 dpi. Over the area of a 6x9 negative I got 106 megapixels. The film could have an infinite resolution- the scan is still the limiting factor.
I have found my Mamiya's lenses to be as good as any. My Mamiya 6 is just like a big Leica.
Should I even rebut somebody who starts his post with "From what I heard..."? It is ironic you simultaneously advertise your ignorance and attempt to lecture others. However, for the sake of other readers, I will respond to your claim that "modern optics for digital cameras drastically increased resolution". This is wrong. The best optics for digital cameras are identical to the best optics for film cameras. Literally identical, you can detach the lens from a digital SLR, attach it to a film camera with the same mount, and resume taking pictures.
"From what I heard, medium format lenses were never that good." No, there exist high quality lenses for medium format cameras, just as there exist high quality lenses for large format cameras, 35mm cameras, and even APS cameras. Even if you get a bit of distortion or chromatic aberration in one of the larger format lenses, increasing your image size by a factor of 6.25 (for medium format) or 15 (for large format) is such a massive improvement that everything else gets lost in the decimal places.
The computation of 110megapixels for a 6x9 negative is correct, even conservative. With higher speed films and some slide emulsions, you will see grain at this resolution, but the people using this sort of equipment will often value the grain and anyway can remove it after scanning if they want to.
The availability of high quality 100+ megapixel images from 30 year old cameras with modern scanners is part of the reason why medium format digital cameras exist, in order to compete. Such cameras have resolutions running from about 50 megapixels to about 150 megapixels.
One might reasonably raise the question of whether any normal user needs resolution above 8 megapixels or so. Certainly one can get excellent images at 4x6 without going higher. But to extrapolate that film is not capable of higher resolution would not be correct.
None of this refers to Leicas, of course. They make nice cameras, but for $9000 what you are mostly buying is a status symbol.
And as for this comment --
"I hope you understand that "lens" is not the same as "piece of glass"."
What a twat.
@stern: "Should I even rebut somebody who starts his post with "From what I heard..."? It is ironic you simultaneously advertise your ignorance and attempt to lecture others."
Well, I wonder who's ignorant. At least I have openly stated that's not my own experience.
"The computation of 110megapixels for a 6x9 negative is correct, even conservative. With higher speed films and some slide emulsions, you will see grain at this resolution, but the people using this sort of equipment will often value the grain and anyway can remove it after scanning if they want to."
I was talking about actual amount of information in the final image - not about scans. And the fact that as you mention grain becomes visible clearly points that you go far above the resolution limit.
Using your logic I can print picture from 10MP E-520 on A1, scan it at high DPI and claim that even my E-520 can produce images of ZOMG gazillionsMP.