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Thread: Mamiya 7 and IQ180 in black and white

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    Mamiya 7 and IQ180 in black and white

    I'm currently working with Lenny Eiger to get some scans of the film we shot for the big camera comparison done (using an Aztek Premiere 8000dpi scanner) and I thought I'd show a quick preview of the Mamiya 7 T-Max scan file alongside the IQ180 ... The Mamiya stands up fairly well. We've obviously got a fair bit of halation in the film and fundamentally it's a very different aesthetic but the fact it's in the ballpark is quite impressive. I've clipped the highlights on the film scan a little by the way but then the jpg compression in the highlights is making a mess of things too..

    http://gbl.bz/mamiya7

    http://gbl.bz/iq180-alpa

    Tim

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    Re: Mamiya 7 and IQ180 in black and white

    Is that T-Max 100 or 400?

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by Jorgen Udvang View Post
    Is that T-Max 100 or 400?
    100

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    Re: Mamiya 7 and IQ180 in black and white

    Thanks for the comparison, Tim. Very instructive.

    Peter

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by timparkin View Post
    We've obviously got a fair bit of halation in the film...
    Where? I looked at the film image and could not see any evidence of halation. It would be a rather odd thing to see with a modern emulation and camera.

    Thanks for the post. The Mamiya 6 was a real favorite of mine and it is interesting to see the comparison.

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    Re: Mamiya 7 and IQ180 in black and white

    There's something I don't understand here:
    - If the film image is scanned at 8,000dpi, it's either downsized or cropped. An 8,000dpi scan of a 6x7cm negative gives 22,000 pixels longest side.

    - When I look at some of my scans of 35mm Delta 100, a film that I thought would be similar to T-Max 100, I don't get the same level of detail as you do with your scan, but still far too much considering the huge difference in film format and the fact that I scanned my negs on a 10 year old Epson 3200 flatbed scanner (4,500 pixels longest side).

    There's something I don't understand here.

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    ClydeR
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    Re: Mamiya 7 and IQ180 in black and white

    I agree, something about this is confusing. I scan TMAX 100 with a Imacon PIII and get less grain, more detail and better contrast than this image shows (assuming the image is not cropped). Lenny has excellent credentials, I fully expect his scans to smoke mine.

    I'd like to see the results of this comparison, but don't understand what's going on well enough for this comparison to work for me.

    Later,

    Clyde

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    Re: Mamiya 7 and IQ180 in black and white

    Here's the original test to show the context of the sample you can see

    Big Camera Comparison – On Landscape

    We'll post more when we've finished the proper comparison...

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    Re: Mamiya 7 and IQ180 in black and white

    Something must have gone wrong during the scan of the Mamiya film file. Here, on the 4x5 file (Delta 100), the scan holds up very well compared to the microscope view:



    But with the M7 example (T-Max 100), the resolution test is falling apart completely when scanned compared to the microscope view:


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    SCHWARZZEIT
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    Re: Mamiya 7 and IQ180 in black and white

    As far as I understand Tim's test, the trumpet chart crops are scaled to the same size as the 4000 ppi scan of the 8x10" reference which puts the Mamiya 7 trumpet at almost 16000 ppi. I agree there are some strange artifacts in that scaled 8000 ppi scan. A good scan should look better than this. On the other hand Lenny's new scan does look really good. If you open the file you can see that it's an 8000 ppi crop of a small area on the film. The contrast of the Mamiya 7 TMX film seems rather low. I'd expext TMX to have more punch.
    My personal interpretation is that for higher contrast details the 6x7 film has a slight advantage in resolution over the IQ180 but for mid to low contrast the IQ180 is better and the overall rendition is much cleaner.

    Tim, did you process Lenny's 8000 ppi scan in terms of noise reduction and sharpening?

    -Dominique

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    Re: Mamiya 7 and IQ180 in black and white

    Hi,

    You need to take into account that the photographs have been framed the same on the different cameras - so the 4x5 has over twice the linear resolution than the 6x7 because it's using over four times the surface area of film.



    and yes the area is quite a dramatic crop (otherwise the scan would only need to be about 2000dpi.

    Quote Originally Posted by ClydeR View Post
    I agree, something about this is confusing. I scan TMAX 100 with a Imacon PIII and get less grain, more detail and better contrast than this image shows (assuming the image is not cropped). Lenny has excellent credentials, I fully expect his scans to smoke mine.
    If you think so I'd be happy to send you some of the film.. Have a check of the test conditions etc and then if you still think you can get less grain and more detail and more contrast, just send me your address ...

    Now we can play with aperture to reduce the grain but at the cost of some resolution - that is an aspect we are looking into.

    Quote Originally Posted by Shashin View Post
    Where? I looked at the film image and could not see any evidence of halation. It would be a rather odd thing to see with a modern emulation and camera.
    Have a look at the circular aperture in the hassleblad - on the IQ180 you get a nice contrast edge whereas with the Mamiya 7 you get a bleed from the centre aperture into the surrounding dark shades.


    Tim

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by SCHWARZZEIT View Post
    As far as I understand Tim's test, the trumpet chart crops are scaled to the same size as the 4000 ppi scan of the 8x10" reference which puts the Mamiya 7 trumpet at almost 16000 ppi. I agree there are some strange artifacts in that scaled 8000 ppi scan. A good scan should look better than this. On the other hand Lenny's new scan does look really good. If you open the file you can see that it's an 8000 ppi crop of a small area on the film. The contrast of the Mamiya 7 TMX film seems rather low. I'd expext TMX to have more punch.
    My personal interpretation is that for higher contrast details the 6x7 film has a slight advantage in resolution over the IQ180 but for mid to low contrast the IQ180 is better and the overall rendition is much cleaner.

    Tim, did you process Lenny's 8000 ppi scan in terms of noise reduction and sharpening?

    -Dominique
    Hi Dominique - yes I did a bit of post processing for noise and also used a large area unsharp mask to help with the halation (40px radius about 20% amount). And some sharpening too.

    Tim

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by SCHWARZZEIT View Post
    I agree there are some strange artifacts in that scaled 8000 ppi scan. A good scan should look better than this.

    -Dominique
    It would of course be interesting to know where the artifacts come from, since they are not there in the microscope view. From what I can gather, they influence the resolution of the image as a whole. Can it be the scanner setting or some mismatch between the grain structure of the film and/or the lens rendering with the scanner? It doesn't look like grain to me

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by timparkin View Post
    and yes the area is quite a dramatic crop

    If you think so I'd be happy to send you some of the film.. Have a check of the test conditions etc and then if you still think you can get less grain and more detail and more contrast, just send me your address ...
    There's no need for that, the link provides the context for the test, the image is a crop. I've figured that I get an equivalent of a bit under 40Mp from the Mamiya 7/PIII combination, which seems reasonably in line with your results (a bit lower resolution than your 4000 dpi scan results). Lenny's scans are better than mine, just what I'd expect.

    Interesting test, thanks.

    Later,

    Clyde

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by Jorgen Udvang View Post
    It would of course be interesting to know where the artifacts come from, since they are not there in the microscope view. From what I can gather, they influence the resolution of the image as a whole. Can it be the scanner setting or some mismatch between the grain structure of the film and/or the lens rendering with the scanner? It doesn't look like grain to me
    If you mean the vertical spiking, it's jitter in the system (possibly in the belt/encoding disk) this causes slightly offsets in each vertical line scan. I have thought about using a single line horizontally as a 'reference' and to 'fix' these using this (should be possible as long as the offset is consistent along a vertical column but I have a feeling it's not).

    At worst it's a slightly speed up/slow down of the rotation as you go through the scan.

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by timparkin View Post
    If you mean the vertical spiking, it's jitter in the system (possibly in the belt/encoding disk) this causes slightly offsets in each vertical line scan. I have thought about using a single line horizontally as a 'reference' and to 'fix' these using this (should be possible as long as the offset is consistent along a vertical column but I have a feeling it's not).

    At worst it's a slightly speed up/slow down of the rotation as you go through the scan.
    I see, but why are we seeing this only in the Mamiya 7 images? Is it a randomly occuring problem?

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by Jorgen Udvang View Post
    I see, but why are we seeing this only in the Mamiya 7 images? Is it a randomly occuring problem?
    Because they are the only 8000dpi scans... (the original 8000dpi scans were done 90 degrees and so the variance is along the trumpet shape rather than across it.

    Tim

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by timparkin View Post
    Because they are the only 8000dpi scans... (the original 8000dpi scans were done 90 degrees and so the variance is along the trumpet shape rather than across it.

    Tim
    How about this one?



    You see, my point is that, while on the 4x5, the 8000dpi scan seems to improve on the microscope view, while on the Mamiya scan, it seems to be the other way around, and quite dramatically so. It might be me who don't understand the methodology her (wouldn't be the first time ), but still...

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by Jorgen Udvang View Post
    How about this one?

    ....

    You see, my point is that, while on the 4x5, the 8000dpi scan seems to improve on the microscope view, while on the Mamiya scan, it seems to be the other way around, and quite dramatically so. It might be me who don't understand the methodology her (wouldn't be the first time ), but still...
    I'm afraid I can't see your point as it doesn't look like the 8000dpi scan improves on the 4x5 view. In fact you'd be hard pushed to say that that 8000dpi scan improves on the 4000dpi scan.

    If you look at the microscope view you can clearly see horizontal lines up to 12 and maybe 13. On the 4000/8000 scan they stop at 10 maybe 11.

    Of course the scan of 4x5 will get more of the full amount out because of the resolution limit of the lenses means you can't put as fine a line down on film, which makes it easier to read by the scanner.

    With the Mamiya 7, the lenses can put down such fine detail that the scanner has difficultly in reading it. The 8000dpi scanner that Lenny has manages better than any other scanner I've tried yet though!

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    Re: Mamiya 7 and IQ180 in black and white

    The 8000dpi scan of the 4x5 is more contrasty than the 4000dpi. In my view, it also shows more detail, although some of that detail is grain. IN my view, scanning to a level where grain becomes visible is an advantage, since it also shows the true character of the film, but no everybody will agree on that.

    What is important is that, since there are strong artifacts on the 8000dpi scan of the Mamiya 7 image, that scan can't be trusted and makes it irrelevant for the comparison. That's a pity, considering all the work that must have gone into this and since for some of us, finding the resolution potential of medium format film gives us an indication of where the limit for our cameras are, at least for the film used in this test.

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by Jorgen Udvang View Post
    The 8000dpi scan of the 4x5 is more contrasty than the 4000dpi. In my view, it also shows more detail, although some of that detail is grain. IN my view, scanning to a level where grain becomes visible is an advantage, since it also shows the true character of the film, but no everybody will agree on that.

    What is important is that, since there are strong artifacts on the 8000dpi scan of the Mamiya 7 image, that scan can't be trusted and makes it irrelevant for the comparison. That's a pity, considering all the work that must have gone into this and since for some of us, finding the resolution potential of medium format film gives us an indication of where the limit for our cameras are, at least for the film used in this test.
    Just to be clear - can you tell me what the 'strong artefacts' you are talking about are?


    I'm not sure what you mean by "can't be trusted" - I've now had three 8000dpi scans done and they all show slightly jitter (if this is the artefacts you are talking about).

    If you have an 8000dpi scanner or can recommend one where you haven't see slight artefacts at 8000dpi, let me know - I'm quite happy to send the film off again.

    As it stands, this is the result that you can be expected to get from your film when scanned - hence trust isn't an issue.

    You should only say "can't be trusted" when someone is trying to con you or that they've screwed up something - can you explain if this is your intent?

    p.s. The 8000dpi scan of the 4x5 isn't as good as Lenny's scan

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    SCHWARZZEIT
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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by timparkin View Post
    Now we can play with aperture to reduce the grain but at the cost of some resolution - that is an aspect we are looking into.

    Tim
    Hi Tim,

    which aperture did Lenny use for this 8000 ppi scan? 3 micron?

    Quote Originally Posted by timparkin
    I'm afraid I can't see your point as it doesn't look like the 8000dpi scan improves on the 4x5 view. In fact you'd be hard pushed to say that that 8000dpi scan improves on the 4000dpi scan.

    If you look at the microscope view you can clearly see horizontal lines up to 12 and maybe 13. On the 4000/8000 scan they stop at 10 maybe 11.

    Of course the scan of 4x5 will get more of the full amount out because of the resolution limit of the lenses means you can't put as fine a line down on film, which makes it easier to read by the scanner.
    It really depends on your criterion what you consider as resolved or not. Especially with line targets this can be difficult. Long lines work in favor of film because film does not have a hard resolution limit. It's just that with higher spatial frequencies the probability decreases that details separated by a fixed contrast gets resolved on film. With long lines you increase that probability that at least at some points of those lines the detail is projected on fine enough grain to be resolved by the film. Our visual system is really good at reconnecting the missing space between the unresolved parts and at the limit it's less clear but you get a feel for resolved detail.

    On the TMX 4x5" shot I can see that there is some detail in those lines up to 13 but I can only count those fifteen lines up to 11 on the microscope image (10 on the 8000 ppi scan and 9 on the 4000 ppi scan).

    Quote Originally Posted by timparkin
    With the Mamiya 7, the lenses can put down such fine detail that the scanner has difficultly in reading it. The 8000dpi scanner that Lenny has manages better than any other scanner I've tried yet though!
    This resembles what I found in my own tests a few years ago. I tested TMX in 35mm with the Canon 1.4/50 lens. At f5.6 I could see about 160 lp/mm on film through a microscope but my ICG drum scanner could only detect a little more than 100 lp/mm, similar to what Lenny could get from the Premier.
    But for all practical means on real world subjects the grain of these films is already obscuring most of the details at those high frequencies that the slight loss from scanning is really insignificant. The only film where I saw a significant real world resolution advantage from an optical print compared to a high-res drum scan has been the microfilm Adox CMS 20. If you want to test what your Mamiya 7 lenses can do you should get some in 120.

    -Dominique

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by SCHWARZZEIT View Post

    which aperture did Lenny use for this 8000 ppi scan? 3 micron?
    3,6,8,10,13,16,19,22
    The one we are looking at is either 6 or 8 -- the three just lost nearly everything in a mass of noise.


    Quote Originally Posted by SCHWARZZEIT View Post
    It really depends on your criterion what you consider as resolved or not. Especially with line targets this can be difficult. Long lines work in favor of film because film does not have a hard resolution limit. It's just that with higher spatial frequencies the probability decreases that details separated by a fixed contrast gets resolved on film. With long lines you increase that probability that at least at some points of those lines the detail is projected on fine enough grain to be resolved by the film. Our visual system is really good at reconnecting the missing space between the unresolved parts and at the limit it's less clear but you get a feel for resolved detail.

    On the TMX 4x5" shot I can see that there is some detail in those lines up to 13 but I can only count those fifteen lines up to 11 on the microscope image (10 on the 8000 ppi scan and 9 on the 4000 ppi scan).
    I agree... although we aren't talking about what is put down on film but what is resolved by the scanner. The film has lines at the 11 or possibly 12 mark according to the microscope (and looking by eye through the microscope resolves more than the photo through the eyepeice) and so it's the scanner that has failed to resolve in this case.

    Quote Originally Posted by SCHWARZZEIT View Post
    This resembles what I found in my own tests a few years ago. I tested TMX in 35mm with the Canon 1.4/50 lens. At f5.6 I could see about 160 lp/mm on film through a microscope but my ICG drum scanner could only detect a little more than 100 lp/mm, similar to what Lenny could get from the Premier.
    But for all practical means on real world subjects the grain of these films is already obscuring most of the details at those high frequencies that the slight loss from scanning is really insignificant.
    yes I agree... the goal at that point is more about clarity of picture, rendering of grain etc

    Quote Originally Posted by SCHWARZZEIT View Post
    The only film where I saw a significant real world resolution advantage from an optical print compared to a high-res drum scan has been the microfilm Adox CMS 20. If you want to test what your Mamiya 7 lenses can do you should get some in 120.
    That is on the cards :-)

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    Re: Mamiya 7 and IQ180 in black and white

    Tim, the Mamiya image is digitally enlarged, isn't it? The Mamiya trumpet is the same size as the 4x5, and it should be about half the size. That pretty easily accounts for the Mamiya looking a fair bit worse side-by-side with the 4x5.

    Later,

    Clyde

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by ClydeR View Post
    Tim, the Mamiya image is digitally enlarged, isn't it? The Mamiya trumpet is the same size as the 4x5, and it should be about half the size. That pretty easily accounts for the Mamiya looking a fair bit worse side-by-side with the 4x5.

    Later,

    Clyde
    Hi Clyde - yes they've all been enlarged digitally in order to show the detail - they've been enlarged to match the microscope photograph.

    So, yes, if you expect these to be 100% pixels then we'd have very different size images (e.g. microscope would be 3x bigger than 8000 which would be 2x bigger than 4000 which would be 2x bigger than the Mamiya 7 4000dpi

    Tim

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by timparkin View Post
    Just to be clear - can you tell me what the 'strong artefacts' you are talking about are?


    I'm not sure what you mean by "can't be trusted" - I've now had three 8000dpi scans done and they all show slightly jitter (if this is the artefacts you are talking about).

    If you have an 8000dpi scanner or can recommend one where you haven't see slight artefacts at 8000dpi, let me know - I'm quite happy to send the film off again.

    As it stands, this is the result that you can be expected to get from your film when scanned - hence trust isn't an issue.

    You should only say "can't be trusted" when someone is trying to con you or that they've screwed up something - can you explain if this is your intent?

    p.s. The 8000dpi scan of the 4x5 isn't as good as Lenny's scan
    I'm talking about the "artifacts" or "noise" shown in the 8000dpi scan in this image:



    If you look at the numbers above the line, there are more detail shown in the 4000dpi scan than in the 8000dpi scan. The fact that all of this, including the lines, come out relatively clear in the microscope view, is a strong indication that this is a scanner limitation and not a film or camera/lens limitation. I can understand that scanner has limitations, and this is obviously something one has to consider when scanning any high resolution film. What puzzles me is that a similar kind of "noise" doesn't show up in the other 8000dpi scans. On the 4x5 scans, the 8000dpi scan shows more detail than the 4000dpi scan, but with the Mamiya, it's the other way around. That doesn't make sense to me. I do understand the implications of the different formats, but still, the quality ratio should go in the same direction, shouldn't it?

    Please don't take it personal when I say "can't be trusted" about the Mamiya 8000dpi scan. What I mean is simply that when the scan doesn't represent properly what's apparently present on the film (ref. the microscope view) within the area of the lines and numbers, the same might be the case for other areas of the image as well.

    If it's true that we are seeing a limitation of the scanner here, and if a rather common film like the T-Max 100 really resolves beyond the abilities of such a high end scanner, it's kind of good news for those of us who like film. Shows that there's still a lot of life left in the old, flimsy rolls of imaging material

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    Re: Mamiya 7 and IQ180 in black and white

    As an aside to all this, I've had an interesting experience with one of my clients the last few weeks. They had acquired 4 different images, one from a photographer and three from a major stock agency (not microstock). The one from the photographer was a 35mm slide (Velvia) and the rest were digital images taken with DSLRs that ranged from 12 to 16 MP. They wanted me to have the images printed at a size around 200 x 130 cm for display on walls around the office.

    It was very easy to conclude that the digital files were way to small for this purpose, and they all fell apart with noise showing up in big blotches in the shadow areas in addition to lack of detail. Still, I thought I'd give the slide a go, mostly to see what the limitations were. To my surprise, the film image looked a lot better when enlarged, and although 200 cm is beyond what it's really capable of, it clearly "survived" the enlargement better than the digital files.

    I don't know the technical information of the digital files other than the size, since the photo agency had stripped that kind of data off the file, but this seems to be an advantage with film that at least I haven't thought about before: The grain structure of film has a more acceptable look when enlarged beyond its capabilities than noise and other artifacts present in digital files. And when observed from a distance, the irregularity of film grain gives a perceived impression of detail rendering that the digital files struggled to do, at least these files.

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    Re: Mamiya 7 and IQ180 in black and white

    Quote Originally Posted by Jorgen Udvang View Post
    I'm talking about the "artifacts" or "noise" shown in the 8000dpi scan in this image:

    [original comparison of mamiya 7 t-max 4000, 8000 and microscope]

    If you look at the numbers above the line, there are more detail shown in the 4000dpi scan than in the 8000dpi scan. The fact that all of this, including the lines, come out relatively clear in the microscope view, is a strong indication that this is a scanner limitation and not a film or camera/lens limitation. I can understand that scanner has limitations, and this is obviously something one has to consider when scanning any high resolution film. What puzzles me is that a similar kind of "noise" doesn't show up in the other 8000dpi scans. On the 4x5 scans, the 8000dpi scan shows more detail than the 4000dpi scan, but with the Mamiya, it's the other way around. That doesn't make sense to me. I do understand the implications of the different formats, but still, the quality ratio should go in the same direction, shouldn't it?
    Yes - as I said in the text, this is a previous 8000 dpi scan that wasn't so good. In addition to this, the scan is enlarged to over 2x that of the 4x5 scans because the 'image' for the 4x5 has been projected onto a lot larger peice of film (hence the scanner hasn't had to do as much work).

    The 8000dpi scan of the 4x5 doesn't really contain more detail either, it's just more contrasty.

    Quote Originally Posted by Jorgen Udvang View Post
    Please don't take it personal when I say "can't be trusted" about the Mamiya 8000dpi scan. What I mean is simply that when the scan doesn't represent properly what's apparently present on the film (ref. the microscope view) within the area of the lines and numbers, the same might be the case for other areas of the image as well.

    If it's true that we are seeing a limitation of the scanner here, and if a rather common film like the T-Max 100 really resolves beyond the abilities of such a high end scanner, it's kind of good news for those of us who like film. Shows that there's still a lot of life left in the old, flimsy rolls of imaging material
    Ah yes, I understand now. Sorry for over-reaction - in which case it's very much true that this is a limitation of scanning systems. Even an 8000dpi scanner can only really get to about 100 lines per mm of detail on the film and T-Max has a potential 140 or more. If you use something like Spur Nano then you can reach 260 lppmm which is only accessible by enlargement.

  29. #29
    Subscriber Member Jorgen Udvang's Avatar
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    Re: Mamiya 7 and IQ180 in black and white

    Hmmm... maybe I want a darkroom

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