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Thread: H3D39 as first step to MFDB/Technical (& vs DSLR)

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    H3D39 as first step to MFDB/Technical (& vs DSLR)

    I'm the editor of a web magazine and we did the big camera comparison test a year ago. We recently tested a H3D39 against a D800 in terms of resolution, colour, usability, etc. and also commented on it's use as a cheap entry point into a technical camera system (we consulted a few retailers and people who have actually researched and gone through this route) and I wondered whether a few excerpts from the test would be of interest to the forum? If I'm not supposed to post anything relating to a commercial activity here just let me know or delete the thread.

    Issue Fifty Six | On Landscape

    Our results suggest that the two cameras are producing almost identical results depending on how you compare the slightly different aspect ratios.

    If you want a 3x4 image and would crop pixels off the D800 to get it then the H3D39 produces a slightly sharper and smoother image.

    If you want a 2x3 ratio image and have to crop the H3D39 then the D800 ends up just a bit sharper (although very close) with smoothness on a par but possibly with the advantage to the H3D39 (at base ISO).

    Now the interesting thing is that colour accuracy was a toss up. The H3D39 got some flourescent materials more accurately but the D800 got foliage a hell of a lot better (the classic yellow greens of the H3D39/P45 chip showed themselves). The H3D39 had problems with a later evening sky where the colours went slightly odd but then again the D800 showed much too strong cyanic blues.

    We used a Sony A900 in one of the tests as a colour reference (that camera is just stunning for colour) and the resolution showed a significant drop from both cameras even in print.

    The H3D39 didn't like rainy weather though and showed some sync issues (magenta splurges).

    http://www.onlandscape.co.uk/wp-cont...4/A6532636.jpg

    The article is subscription only but here's a few samples of comparisons

    The first shows the advantage to the H3D39 when cropping the D800

    http://static.timparkin.co.uk/static...test/dpi1.html

    The second shows the sunset shot with the colour comparison

    http://static.timparkin.co.uk/static...test/dpi2.html

    The third shows the difference in foliage colours

    http://static.timparkin.co.uk/static...test/dpi3.html

    The first comparison also includes a frame taken with Portra 160 on the 645 film back. The 645 film back has a disadvantage because we were using the same lens as the digital back test whereas in fact the film has more surface area. Even so it's obvious that film can't compete at this scale (scans done on a well tuned Howtek drum scanner).

    I would expect you'd need 6x7 for film to compete. It should be noted that transparency film retains more detail in a scan and we'll perhaps repeat the test with Provia next time and try to find a subject where we can zoom in/out to keep area the same.

    The last test includes the Sony A900 for a colour reference. Just click on the 'names' underneath the picture to choose your comparison.

    We also printed the results at various sizes to see if there was any visible difference when shown to members of the public and the answer for our particular test was that there wasn't any in terms of sharpness (the public don't tend to be great at this anyway). The photographers we showed the test too couldn't tell the difference when the prints were separate, only when they were shown side by side. We printed up to 20x24 and printed a sample at 40" long edge and 60". The cleanliness of the H3D39 showed through at 60" when compared side by side though when cropping the D800. I think this would be a very close thing if you cropped the H3D39 to give a 2x3 ratio image.

    I'm happy to answer questions about the test if anyone is interested?

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Just wondering what lens was used and how the files were processed. I use the H3D39 on a daily basis for portrait and head shot work, and I do not think the Nikon can match it at all in this area. Cannot comment on the landscape stuff but surprised from what I have seen in the past for the H3 landscape images. The lenses are different. The processing is different. The sensor size is different. The DOF is different. The pitch is different. The images are different. Not sure why people do not see this. Regards Martin

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    I think people do see that pictures are different, mainly in color as bokeh is rarely a big factor in landscape. But there's one thing to see that they are different, another to decide which one is better.

    Comparing to a DSLR and especially this almost unmentionable camera is always a controversial thing, especially in this forum . I would expect the H3D39 to perform better in a comparison of portraiture with manufactured-provided processing pipelines.

    I think the big strength with MFD in landscape is ability to use the back on tech cameras. It is possible with the H3D39 too, with the mess of having to use external power, but as H cameras and backs is among the cheaper gear you can get second hand it can be worth it.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    It's a wash to my eyes in these samples.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    A little off track here but as a subscriber to On Landscape I can say that the
    magazine is superb...look forward to each issue and do enjoy the ability to load PDF version into an iPad mini and carry it with me.

    Very experience group of writers and great format...plus all the fabulous UK landscapes....so jealous of your backyard!

    Having used a H3D II 39 with H body and on an Alpa and an A900 Sony I an not surprised at the findings....looks like I may have to look a bit closer at the D800...although I prefer the larger Nikon and Canon bodies and believe that there are few lenses in 35 that approach the level of MF lenses from Hasselblad, Leica, Rodenstock and Schneider. I have toyed with the idea of buying another A900 as the color is profoundly good.

    Nice to see your post Tim and I will look closer at the issue today. Hope to see more input like this and the article on the Canon 1Dx was superb.

    Regards,

    Bob

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by MartinE View Post
    Just wondering what lens was used and how the files were processed. I use the H3D39 on a daily basis for portrait and head shot work, and I do not think the Nikon can match it at all in this area. Cannot comment on the landscape stuff but surprised from what I have seen in the past for the H3 landscape images. The lenses are different. The processing is different. The sensor size is different. The DOF is different. The pitch is different. The images are different. Not sure why people do not see this. Regards Martin
    The cameras are different - in the article we talk about lenses and the way that buying into medium format brings you a range of quality glass. Also, shooting a more square image plays to the H3D39's strengths and possibly the colour rendering is more suitable for portraits.

    I think I noticed that the cameras and lenses were different :-) The depth of field was the same because we scaled it in relation to the aperture though.

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by MartinE View Post
    Just wondering what lens was used and how the files were processed. I use the H3D39 on a daily basis for portrait and head shot work, and I do not think the Nikon can match it at all in this area. Cannot comment on the landscape stuff but surprised from what I have seen in the past for the H3 landscape images. The lenses are different. The processing is different. The sensor size is different. The DOF is different. The pitch is different. The images are different. Not sure why people do not see this. Regards Martin
    p.s. we used the 60mm Hasselblad and the 50mm Nikon 1.8 G - we tested the 60mm lens on the Nikon via a Mirex adapter and it was very sharp - definitely outresolved the Hasselblad.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    The H3D39 got some flourescent materials more accurately but the D800 got foliage a hell of a lot better (the classic yellow greens of the H3D39/P45 chip showed themselves).
    This concerns me, do you have any idea if the p65+ shares the same colours as the P45+, Tim?

    I am due to purchase a P65+ with an Arca Swiss RM3Di and hope this back produces better greens. The D800 colours look fantastic to my eye, as does the resolution.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Never mind, I just did a search to find they're are indeed different :-)

    Can't wait to get out in the field with the new kit!

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    p.s. we used the 60mm Hasselblad and the 50mm Nikon 1.8 G - we tested the 60mm lens on the Nikon via a Mirex adapter and it was very sharp - definitely outresolved the Hasselblad.
    There is no 60mm HC lens.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Maybe a C(xx) 60 f3.5 lens with CF-adapter...?

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by JGR View Post
    This concerns me, do you have any idea if the p65+ shares the same colours as the P45+, Tim?

    I am due to purchase a P65+ with an Arca Swiss RM3Di and hope this back produces better greens. The D800 colours look fantastic to my eye, as does the resolution.
    The P65+ has an entirely different sensor, a Dalsa FTF9168C. P45+ has a Kodak KAF-39000. Color of the P65+ is different, and concerning accuracy it's better. I would not worry.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by torger View Post
    The P65+ has an entirely different sensor, a Dalsa FTF9168C. P45+ has a Kodak KAF-39000. Color of the P65+ is different, and concerning accuracy it's better. I would not worry.
    Yes I've seen a lot better colour from the P65+ sensor - we'll be testing the IQ180 vs IQ260 colour in a future issue of the magazine.. we'll also try to include as many older backs as possible

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Udo View Post
    Maybe a C(xx) 60 f3.5 lens with CF-adapter...?
    I believe it was although I'll check with Andrew Nadolski who set up the test. We mounted the lens to our Nikon via a Mirex adapter so that suggests it was an older lens. As I noted the resolution was fine as we checked on the D800.

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    I have the 28mm HCD and do use for landscape sometimes, With Phocus I see great results from many other photographers and would recommend this set up to anyone looking at Medium format with the H3D39. To me it just works.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Tim, I have no idea what you're test is all about as your article is a paid subscription only (?) and can only go off your very brief comments here but I just don't understand what your goal is with this sort of test.

    In all the years I've had a keen interest in photography I have never used a capture medium (neg, trans, digital) that renders all colours 100% accurate. Film was chosen on it colour characteristic, shadow or highlight rendering or resolution (grain structure) and I don't think there existed a film that was good at everything. Digital is just the same so nothing has changed apart from its the camera's that dictate the colour rather than the film we put in them today.

    Today, if I photograph something with my P65, 1Ds3 or iPhone the colours are infinitely adjustable to the desired level so why absolute capture accuracy is so important I have no idea. After all, we are not talking about one camera seeing green as red etc. And what is accurate colour in a landscape photograph?

    If you were conducting a test for use in a repro environment and you custom profiled the cameras to your lighting and one camera registered red as a brown then there might be some basis for discussion but in landscape my idea of a good green is probably not yours and ultimately it's probably not a value that should be measured for accuracy.
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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Perhaps not in landscape but in repro, fashion, product, etc it is very very important.
    I am not a painter, nor an artist. Therefore I can see straight, and that may be my undoing. - Alfred Stieglitz

    Website: http://www.timelessjewishart.com

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Ben Rubinstein View Post
    Perhaps not in landscape but in repro, fashion, product, etc it is very very important.
    Yes, the ultimate goal in repro but this article discussed colour accuracy in landscape photography.

    A good comparison yes but not something I'd ever be overly worried about and not something I'd base a buying decision on because a D800 shoots better (subjectively) greens than a HD39.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    I believe it was although I'll check with Andrew Nadolski who set up the test. We mounted the lens to our Nikon via a Mirex adapter so that suggests it was an older lens. As I noted the resolution was fine as we checked on the D800.

    Tim
    I believe it is just a typo. Is it 50mm HC?
    To conduct the study this intensive, would you just use the HC or HCD lens? It doesn't make sense to me to use other types of lens.
    I have Hasselblad H4D-40, Nikon D800E and IQ180/DF/Cambo (still have all of them). I don't have them for only few days but for over a year and more and have used them as a regular basis.
    I shoot landscape only and, although the D800E is an outstading camera, I don't believe the pictures from Nikon D800E look the same as from the other 2 cameras in big prints.
    Dynamic range of the D800E is better than both the Hasselblad and P1 but the the color and depth when printing big is not as good. The same as digital which is still not as good as film (but much more convenient to use).
    It's just from amateur eyes who takes landscape photography for many years, not a test.
    Thanks,
    Pramote

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Hi,
    I also think that you should test the D800 against the newer backs, like an IQ140. I believe this is like testing an IQ140 versus a D700. Not talking of resolution, just the technology time frame of when these were out as new. I think even a H4D-31 would have been a closer comparison,it's more entry level pricing now too. I don't know exactly when the 39 sensor came out, but I feel like its at least 4-5 years old... I see you are in the UK, but if you come to the states, I'm happy to do some tests with you in Central Park with my H4x/IQ140 and your d800!!! I'd be very interested in seeing the results. I do own a D800E and I just prefer the h4x/iq combo for almost everything. But thats mostly portraiture and I think thats where mfbd's shine. The d800e is great though and I use it now mainly for video. You also can't compare the cost, etc. and I NOT suggesting people don't use the d800/e and must buy mfdb. My comments are strictly related to actually wanting to do a comparison between the two formats for that specific purpose. To be honest, I really wanted the d800e to replace my mfdb setup. It would have freed up a lot of money. But I just didn't feel like I could/wanted to do that after testing them.

    Cheers,
    Josh

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    I've read the test, and the purpose was to look at what popular second hand alternatives can perform compared to a D800. An H3D-39 can be had second hand at a similar price point as a new D800 system with pro lenses. The test was aimed at price-sensitive amateur users, such as myself.

    I think it's a really great initiative, usually MFD reviews is about looking at $50K systems which very few landscape amateurs will afford. There's a growing amateur interest in MFD and it's actually a quite good market today for getting into MFD second hand, you can get great image quality for reasonable prices. This tests is a brief look into how good it is.

    The article also looks into possibilities of using the digital back on a tech camera, which I personally think is the way to go. I would never have bought my digital back if I was going to use it on a H or 645DF camera and it was about image quality alone, but with my tech camera I would enjoy a 22 megapixel back more than a D800, just because the tech camera is so different and fun to shoot.

    For me it was not important that the digital back would deliver better image quality than the best DSLR, just adequate quality to a reasonable price. This test certainly shows that the H3D-39 despite its age still delivers competitive image quality. It's about showing amateurs that the MFD is today not necessarily only reserved for working professionals and the super-rich, but at the same time not bring inflated expectations (the format wars tend to exaggerate the capabilities of a particular format). I think the articles succeed quite well in being neutral, ie neither being a DSLR or an MFD fanboy, which is kind of refreshing...

    When I help out with gear recommendations to other amateurs I generally focus on the camera, how fun it is to work with and how well it fits the desired shooting style. If you just want a DSLR with better image quality you're generally in for disappointment, or a very big hole in your pocket...
    Last edited by torger; 19th April 2013 at 07:13.
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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    For landscape photography, the only difference between professionals and serious amateurs is that serious amateurs only do photography for passion. Some amateurs I know of having more knowledge in photography than most professionals. I don’t talk about Jack, Guy, Bob, Dan or Ed here.

    You don’t need to be super rich to have MFDB nowsday, there are plenty of opportunities in a second hand market. If you don’t eat out too frequent, don’t buy a new car every few years and just stick with your old woman etc, you still can buy a MFDB.

    Some people are very religious about view or tech cameras but to me it is not the only factor to buy MFDB. Only DSLR with MFDB alone is a good reason to buy a MFDB. I still get sharper prints than Galen Rowell although sharp image is not everything, isn’t it? Photography is about the final result, not only a sharp image or great DOF. To me, super sharp from 2 feet to infinity is not natural to my eyes.

    Taking photography is about pleasure. Whatever you use, 16, 22, 36, 40, 60, 80 mp, it doesn’t matter, just have fun and don’t loan to buy equipments if you are not professionals. Your kids’ college comes first.

    Happy weekend!
    Pramote
    Last edited by Landscapelover; 19th April 2013 at 09:31.
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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Pramote, +1

    I have to agree that the color "test" is meaningless--it actually shows nothing. And since we have no idea what the original scene actually was, we cannot even decide if the camera did produce pleasing color, let alone accurate ones. It makes no sense choosing another camera as a reference when we don't even know how that reproduces color.
    Last edited by Shashin; 19th April 2013 at 10:07.
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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Landscapelover View Post
    ....
    You donít need to be super rich to have MFDB nowsday, there are plenty of opportunities in a second hand market. .... just stick with your old woman etc, you still can buy a MFDB.

    ....
    Pramote

    Please, please, please, Pramote! You're setting up a lot of guys here for a serious hurting....


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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by kdphotography View Post
    Please, please, please, Pramote! You're setting up a lot of guys here for a serious hurting....

    He did not mean you had to keep living with your mother, but your wife...





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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    I have to agree that the color "test" is meaningless--it actually shows nothing.
    I think it helps looking at a previous test done by the onlandscape team:

    http://static.timparkin.co.uk/static...t-2/800px.html

    There one can see that the IQ180, Sony A900, and even portra and velvia looks kind of similar, but P45+ has a green color of its own. I'm guessing that Tim had this test in the back of his head (I'm quite sure he did not like the P45+ colors, but I hope he'll comment later on) when he did this and did not really present as much of the background as he would have needed this time around.

    I'm a bit skeptical about the color of the KAF-39000 sensor, as pleasing greens is important to me. Maybe custom color profiling can fix it, but if there's metamerism issues it's not so sure. I'm glad that I chose a back with a Dalsa 33 megapixel sensor which have competitive color accuracy even with today's standards.

    Had I got a great deal on a KAF-39000-equipped back or so I could live with it, it's not thaaaat important with accuracy for me. But would I choose between for example long exposure support and very accurate colors I think I'd choose colors. I think it's nice starting off with an as realistic rendition as possible when starting to tweak in post, rather than having to tweak to get to a realistic starting position.
    Last edited by torger; 19th April 2013 at 12:14.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    To my eye's the Blad is far superior and what 60mm hasselblad lens was used as there is no HC-60....

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    He did not mean you had to keep living with your mother, but your wife...





    Actually, I meant living with a "mother" so you save monthly mortgage
    Pramote
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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by torger View Post
    I think it helps looking at a previous test done by the onlandscape team:

    http://static.timparkin.co.uk/static...t-2/800px.html

    There one can see that the IQ180, Sony A900, and even portra and velvia looks kind of similar, but P45+ has a green color of its own. I'm guessing that Tim had this test in the back of his head (I'm quite sure he did not like the P45+ colors, but I hope he'll comment later on) when he did this and did not really present as much of the background as he would have needed this time around.

    I'm a bit skeptical about the color of the KAF-39000 sensor, as pleasing greens is important to me. Maybe custom color profiling can fix it, but if there's metamerism issues it's not so sure. I'm glad that I chose a back with a Dalsa 33 megapixel sensor which have competitive color accuracy even with today's standards.

    Had I got a great deal on a KAF-39000-equipped back or so I could live with it, it's not thaaaat important with accuracy for me. But would I choose between for example long exposure support and very accurate colors I think I'd choose colors. I think it's nice starting off with an as realistic rendition as possible when starting to tweak in post, rather than having to tweak to get to a realistic starting position.
    Actually, that test does not answer anything. All you have is a personal perception of an image, but you still have no idea about the color. None of the so-called color tests really test for color. Especially since we do not know what the original scene was, we have no better idea of the results. All you can say is a camera can make a seemingly accurate real color image, but can't go beyond that. And since every camera can make a relatively accurate real color image, the choice is simply random.

    Cameras do not suffer from metamerism and in fact has nothing to do with camera profiles or how a camera reproduces stuff. Metamerism is about two different materials that appear the same color under one light source, but no longer match under another.
    Last edited by Shashin; 19th April 2013 at 15:59.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Landscapelover View Post
    Actually, I meant living with a "mother" so you save monthly mortgage
    Pramote


    And here I was thinking about how expensive divorce can be. And how heartbreaking if your partner gets you camera stuff in the settlement.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    Actually, that test does not answer anything. All you have is a personal perception of an image, but you still have no idea about the color. None of the so-called color tests really test for color. Especially since we do not know what the original scene was, we have no better idea of the results. All you can say is a camera can make a seemingly accurate real color image, but can't go beyond that. And since every camera can make a relatively accurate real color image, the choice is simply random.

    Cameras do not suffer from metamerism and in fact has nothing to do with camera profiles or how a camera reproduces stuff. Metamerism is about two different materials that appear the same color under one light source, but no longer match under another.
    Well cameras do suffer from sensitivity metamerism, there's even a standardized way to measure this, ISO17321. DxoMark has measured this and not surprisingly the KAF-39000 backs is a little bit behind on this, and the Sony camera is one of the best (IQ180 is extremely good too, all Dalsa-based backs are great in that respect, and that's also what I've seen many user opinions, Dalsa more accurate, some still prefer Kodak look).

    I'm no expert on this, so I borrowed an explanation: "the underlying physics is that a sensor can distinguish exactly the same colors as the average human eye, if and only if the spectral responses of the sensor can be obtained by a linear combination of the eye cone responses. These conditions are called Luther-Ives conditions, and in practice, these never occur. There are objects that a sensor sees as having certain colors, while the eye sees the same objects differently, and the reverse is also true."

    Anyway, when the tester's in the review text claim to see with his eyes (being at the scene) the same as scientific measurements show, and images from the scene show that one is significantly different from the others I think everything point towards the same thing: KAF-39000 and greens is a bit tricky... if it's a problem is up to you though.

    It's not a test intended to be pro or against MF, it's a test intended to give some good input to an amateur that probably owns and uses a DSLR and considers getting into MF by buying older generation second hand gear.

    But anyway, I'm not the one that should defend this test, I hope Tim jump in and comment. Not publishing the full text when linking to it here was probably not that wise, as I think the full text is required to appreciate what the review is about.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by gazwas View Post
    Tim, I have no idea what you're test is all about as your article is a paid subscription only (?) and can only go off your very brief comments here but I just don't understand what your goal is with this sort of test.
    The goal was to look at the H3D39 as a stepping stone into the world of medium format digital cameras in the context of people who are already familiar with DSLRs and also in the context of landscape photography. We also looked at the way that this first step is also into the world of digital technical view camera systems.


    Quote Originally Posted by gazwas View Post
    In all the years I've had a keen interest in photography I have never used a capture medium (neg, trans, digital) that renders all colours 100% accurate. Film was chosen on it colour characteristic, shadow or highlight rendering or resolution (grain structure) and I don't think there existed a film that was good at everything. Digital is just the same so nothing has changed apart from its the camera's that dictate the colour rather than the film we put in them today.
    Correct - so choosing a camera that has an intrinsic rendering that matches the way you see the landscape is important.


    Quote Originally Posted by gazwas View Post
    Today, if I photograph something with my P65, 1Ds3 or iPhone the colours are infinitely adjustable to the desired level so why absolute capture accuracy is so important I have no idea. After all, we are not talking about one camera seeing green as red etc. And what is accurate colour in a landscape photograph?
    Wrong - all sensors see colour differently from human vision. The fact that most cameras 'get away with it' just means they are close enough - not perfect.

    One example is the way Leica M8 reacted to infra red but the other classic example for me is the way that the P45 and hence the Hasselblad H3D39 react to greens. As Anders Torger has said, we showed this in the free to access article "Big Camera Comparison" where nearly all of the sensors agreed within certain bounds but for greens the P45 was way off.


    Quote Originally Posted by gazwas View Post
    If you were conducting a test for use in a repro environment and you custom profiled the cameras to your lighting and one camera registered red as a brown then there might be some basis for discussion but in landscape my idea of a good green is probably not yours and ultimately it's probably not a value that should be measured for accuracy.
    [/QUOTE]

    Got to disagree and this is not just about getting a "good" green but about having enough colour separation in colours that are important in order to be able to separate them in post processing. For instane, Velvia 50 doesn't record accurately but provides a huge amount of colour separation and hence for certain renderings of the landscape this can't be emulated in digital to any great extent (most people just add saturation instead).

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by torger View Post
    For me it was not important that the digital back would deliver better image quality than the best DSLR, just adequate quality to a reasonable price. This test certainly shows that the H3D-39 despite its age still delivers competitive image quality. It's about showing amateurs that the MFD is today not necessarily only reserved for working professionals and the super-rich, but at the same time not bring inflated expectations (the format wars tend to exaggerate the capabilities of a particular format). I think the articles succeed quite well in being neutral, ie neither being a DSLR or an MFD fanboy, which is kind of refreshing...
    Glad you got the intention of the article - the idea is to show that an entry level MFDB is 'in the same ballpark' as the D800 and it brings you a whole new level of lenses and the possibility of using it as a technical camera. On top of a beautiful MF DSLR camera..

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    Actually, that test does not answer anything. All you have is a personal perception of an image, but you still have no idea about the color. None of the so-called color tests really test for color. Especially since we do not know what the original scene was, we have no better idea of the results. All you can say is a camera can make a seemingly accurate real color image, but can't go beyond that. And since every camera can make a relatively accurate real color image, the choice is simply random.

    Cameras do not suffer from metamerism and in fact has nothing to do with camera profiles or how a camera reproduces stuff. Metamerism is about two different materials that appear the same color under one light source, but no longer match under another.
    Ermm... if you think every camera can make a seemingly accurate colour image then you have the dubious privilege of being happy with any camera. I for one am not..

    And cameras do suffer from metamerism.. take a look at this picture and explain the colours in another way ..

    http://www.timparkin.co.uk/wp-conten...comparison.jpg

    Your definition of metamerism is only partially correct and refers to "illuminant metameric failure". "Observer metameric failure" is where the observer systems produce different results and is relevant to digital sensors as much as colour blindness in human vision systems.

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post

    I have to agree that the color "test" is meaningless--it actually shows nothing. And since we have no idea what the original scene actually was, we cannot even decide if the camera did produce pleasing color, let alone accurate ones. It makes no sense choosing another camera as a reference when we don't even know how that reproduces color.
    Well if we look at the Big Camera Comparison, we have a result where the IQ180, Sony A900, Velvia and Portra all produce similarish colour relationships. However the Phase P45 showed quite a different colour.

    Now we can either conclude that the IQ180, Portra, Velvia and Sony are all showing something coincidentally similar and incorrect or that that have all got within a certain tolerance of accurate colour.

    Statistically and heuristically speaking the former is very unlikely.

    as the P45 showed a different colour we can be reasonably assured that the colour is 'incorrect' in some way.

    Or if we're P45 owners we can assume that Portra, Velvia, the IQ180 and the Sony are all crap :-)

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    Ermm... if you think every camera can make a seemingly accurate colour image then you have the dubious privilege of being happy with any camera. I for one am not..

    And cameras do suffer from metamerism.. take a look at this picture and explain the colours in another way ..

    http://www.timparkin.co.uk/wp-conten...comparison.jpg

    Your definition of metamerism is only partially correct and refers to "illuminant metameric failure". "Observer metameric failure" is where the observer systems produce different results and is relevant to digital sensors as much as colour blindness in human vision systems.

    Tim
    Here Tim, this is an article about metamerism:

    http://en.wikipedia.org/wiki/Metamerism_(color))

    It has to do with objects and human observers, not cameras. Cameras, unlike humans, have the same spectral response. And it still come down to observing two different objects that appear to have the same color. It is not that the observer sees them as the same, but the colors match. It has nothing to do with color accuracy or whether two observers see the same color. Your example is easy to explain--two different color profiles.

    As for you being pleased by one camera and not another, purely subjective. You still cannot claim that one is better than the other, at least with what you have shown.

    I also prefer color from some cameras over others, but I don't claim my personal preference as anything more than preference. It also take me some time to understand how the camera reproduces color. A few test images are not enough. And as soon as you start processing, color starts changing.

    ...then you have the dubious privilege of being happy with any camera. I for one am not...
    BTW, you don't have to be so condescending towards me. Perhaps I understand the complexities of color and so understand the arbitrary nature of your tests.
    Last edited by Shashin; 21st April 2013 at 07:40.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    Well if we look at the Big Camera Comparison, we have a result where the IQ180, Sony A900, Velvia and Portra all produce similarish colour relationships. However the Phase P45 showed quite a different colour.

    Now we can either conclude that the IQ180, Portra, Velvia and Sony are all showing something coincidentally similar and incorrect or that that have all got within a certain tolerance of accurate colour.

    Statistically and heuristically speaking the former is very unlikely.

    as the P45 showed a different colour we can be reasonably assured that the colour is 'incorrect' in some way.

    Or if we're P45 owners we can assume that Portra, Velvia, the IQ180 and the Sony are all crap :-)

    Tim
    I'm not one to question your observations which in the end spur subjective debate. However, it does make me wonder.

    In all the years that these backs with that Kodak sensor were in use for so many critical applications, this is the first I've read of such a color inaccuracy. Interesting that it is coming to light only now.

    Like some others have observed here, my personal encounter with the 39 meg backs didn't seem to reveal results in keeping with your observations. Over the years, I used the H3D/39 being discussed, a CF39 in both one shot and Multishot modes mounted to a H2F camera, and the H3D-II/39 ... all using that same sensor. I never used the P45, so cannot comment.

    The context of use was mostly commercial product photography, jewelry, glass products, food, including even critical color fabric swatches for General Motors; some car work; other work ranging from outdoor product demos to ground's photos of a memorial park that were as close to landscape as I get; all the way to industrial and corporate portraiture.

    I still question which lens was used. Using a Zeiss CFi-60/3.5 would require a CF adapter on the Hasselblad H camera to enable cocking of the leaf shutter, and that lens could also be used on a 35mm DSLR because it has a mechanical aperture control ... however, no Hasselblad HC or HCD can be mounted on any 35mm DSLR because they are leaf-shutter lenses with a fully electronic interface including aperture control. The only fully electronic interface adapter allowing an HC or HCD lens on another camera is the Leica H to S adapter for the S2/S2P and S camera.

    I also wonder what software was used and the skill level of the user on that software? It is well established lore that Professional users of Hasselblad products consider FlexColor and subsequently Phocus as producing the truest color renderings, especially for color critical commercial works ... a proprietary aspect that Hasselblad has appropriately named "True Color".

    Just a few thoughts.

    -Marc
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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    Well if we look at the Big Camera Comparison, we have a result where the IQ180, Sony A900, Velvia and Portra all produce similarish colour relationships. However the Phase P45 showed quite a different colour.

    Now we can either conclude that the IQ180, Portra, Velvia and Sony are all showing something coincidentally similar and incorrect or that that have all got within a certain tolerance of accurate colour.

    Statistically and heuristically speaking the former is very unlikely.

    as the P45 showed a different colour we can be reasonably assured that the colour is 'incorrect' in some way.

    Or if we're P45 owners we can assume that Portra, Velvia, the IQ180 and the Sony are all crap :-)

    Tim
    So, you have shown that most have a "similar" color rendering and one does not. We have no idea about the quality of the rendering of any of them. We also don't know why one is the outlier--you don't have enough data points to say the cause and so the outlier could be down to human error for all we know. We could do a little research and find out if there are an unusual number of complaints about the color from the p45+. If your "test" is actually showing it is an outlier, then there should be plenty of evidence. If not, that points back to a flaw in your test.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    I'm not one to question your observations which in the end spur subjective debate. However, it does make me wonder.

    In all the years that these backs with that Kodak sensor were in use for so many critical applications, this is the first I've read of such a color inaccuracy. Interesting that it is coming to light only now.

    [/QUOTE]

    Well I can either ignore the evidence of my own eyes and kowtow to your communication of everybody elses experience or believe my own eyes - as a scientist I tend to do the later (with a dose of doubt).

    Quote Originally Posted by fotografz View Post

    Like some others have observed here, my personal encounter with the 39 meg backs didn't seem to reveal results in keeping with your observations. Over the years, I used the H3D/39 being discussed, a CF39 in both one shot and Multishot modes mounted to a H2F camera, and the H3D-II/39 ... all using that same sensor. I never used the P45, so cannot comment.

    The context of use was mostly commercial product photography, jewelry, glass products, food, including even critical color fabric swatches for General Motors; some car work; other work ranging from outdoor product demos to ground's photos of a memorial park that were as close to landscape as I get; all the way to industrial and corporate portraiture.
    Same thing again - perhaps you didnt' photograph anything that strongly triggered the metameric shifts discussed or when you did you didn't notice? Did you ever notice any shifts in colour relationships of objects under different light sources? I only ask as illuminant metameric failure does exist and it's only noticed now and again.

    Quote Originally Posted by fotografz View Post
    I still question which lens was used. Using a Zeiss CFi-60/3.5 would require a CF adapter on the Hasselblad H camera to enable cocking of the leaf shutter, and that lens could also be used on a 35mm DSLR because it has a mechanical aperture control ... however, no Hasselblad HC or HCD can be mounted on any 35mm DSLR because they are leaf-shutter lenses with a fully electronic interface including aperture control. The only fully electronic interface adapter allowing an HC or HCD lens on another camera is the Leica H to S adapter for the S2/S2P and S camera.
    It was a Zeiss 60mm then..

    Quote Originally Posted by fotografz View Post

    I also wonder what software was used and the skill level of the user on that software? It is well established lore that Professional users of Hasselblad products consider FlexColor and subsequently Phocus as producing the truest color renderings, especially for color critical commercial works ... a proprietary aspect that Hasselblad has appropriately named "True Color".
    Andrew Nadolski whose H3D39 we used processed the images in both Phocus and lightroom.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    Same thing again - perhaps you didnt' photograph anything that strongly triggered the metameric shifts discussed or when you did you didn't notice? Did you ever notice any shifts in colour relationships of objects under different light sources? I only ask as illuminant metameric failure does exist and it's only noticed now and again.
    Can you post some evidence of illuminant metamerism? So far you have posted nothing that shows this. If it the image you used in your reply to me, that is not metamerism.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    So, you have shown that most have a "similar" color rendering and one does not. We have no idea about the quality of the rendering of any of them. We also don't know why one is the outlier--you don't have enough data points to say the cause and so the outlier could be down to human error for all we know. We could do a little research and find out if there are an unusual number of complaints about the color from the p45+. If your "test" is actually showing it is an outlier, then there should be plenty of evidence. If not, that points back to a flaw in your test.

    Actually if our test doesn't show it to be an outlier then Portra, Velvia, IQ180 and Sony A900 will be showing 'incorrect colour' ....

    Plus, having spent a long time in the english countryside full of agricultural greens I'm fairly sure which looks correct and which looks wrong.

    Tim

    p.s. take a look at this image a part of a bunch of flowers. The images was clibrated with an IT8 target and the resultant target is a visual match bar slight variations in saturation. The colours are quite different though.

    http://static.timparkin.co.uk/static...-sat-sharp.jpg

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    Can you post some evidence of illuminant metamerism? So far you have posted nothing that shows this. If it the image you used in your reply to me, that is not metamerism.
    Actually the image I showed demonstrated observer metamerism.

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    Actually the image I showed demonstrated observer metamerism.

    Tim
    Actually Tim, it does not.

    In order for you to do that you would need a photograph of two objects, say a red wool sweater and a red silk tie, where the colors of those objects appear the same in the image. Then you would need to photograph the sweater and tie with another system and in the resulting image would show a mismatch between the reds, but not between the two photographs, but between the two objects. Metamerism has nothing to do with color accuracy.

    You are not the first photographer not to understand metamerism.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    Actually the image I showed demonstrated observer metamerism.

    Tim
    Here's an example of illuminant metamerism

    http://4.bp.blogspot.com/-x7rtJ6peuQ...ism-gloves.jpg

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    Actually Tim, it does not.

    In order for you to do that you would need a photograph of two objects, say a red wool sweater and a red silk tie, where the colors of those objects appear the same in the image. Then you would need to photograph the sweater and tie with another system and in the resulting image would show a mismatch between the reds, but not between the two photographs, but between the two objects. Metamerism has nothing to do with color accuracy.

    You are not the first photographer not to understand metamerism.
    So I've shown you some moss and a fern that look the same under one system and then a mismatch under another system... er....

    You're not the first person to make a mistake on a forum...

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    ...

    You are not the first photographer not to understand metamerism.
    p.p.s that comment was very presumptuous and patronising but you're not the first photographer on a forum to be so :-)

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    Here Tim, this is an article about metamerism:

    Metamerism (color) - Wikipedia, the free encyclopedia)

    It has to do with objects and human observers, not cameras. Cameras, unlike humans, have the same spectral response. And it still come down to observing two different objects that appear to have the same color. It is not that the observer sees them as the same, but the colors match. It has nothing to do with color accuracy or whether two observers see the same color. Your example is easy to explain--two different color profiles.
    You really should familiarise yourself with the scientific literature, not just read wikipedia.

    http://www.cis.rit.edu/mcsl/research/PDFs/Spec_Met.pdf

    This is nothing to do with colour profiles, it's to do with the interaction of the emission spectra of the object being photographed and the transmission spectra of both the colour filter array and the silicon sensor beneath.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    Actually Tim, it does not.

    In order for you to do that you would need a photograph of two objects, say a red wool sweater and a red silk tie, where the colors of those objects appear the same in the image. Then you would need to photograph the sweater and tie with another system and in the resulting image would show a mismatch between the reds, but not between the two photographs, but between the two objects. Metamerism has nothing to do with color accuracy.

    You are not the first photographer not to understand metamerism.
    Quote Originally Posted by Shashin View Post
    Here Tim, this is an article about metamerism:

    Metamerism (color) - Wikipedia, the free encyclopedia)

    It has to do with objects and human observers, not cameras. Cameras, unlike humans, have the same spectral response. And it still come down to observing two different objects that appear to have the same color. It is not that the observer sees them as the same, but the colors match.
    Hi Shashin,

    I've just been rushing to catch a train but I'm now sitting with a bit of spare time so I thought I'd discuss a few things relating to metamerism.

    The idea of metamerism doesn't have any reliance on a human observer, although the majority of literature talks about biological systems and you could be mistaken to think this was so.

    The spectral energy of a system can be defined as the combination of the illuminant spectral power distribution, the surface reflectance function and the sensor spectral response (which for a bayer sensor is itself is a combination of the colour filter array tramission spectral response and the silicon spectral absorption).

    So E is illuminant, S is the subject reflectance spectrum and C is the sensor response.

    The "colour" of the object is then derived from three of these spectral energies using a tristimulus approximation.

    Pr = E.S.Cr
    Pg = E.S.Cg
    Pb = E.S.Cb

    However for a single colour in the tristimus you can have many different illuminants **or sensors** that will create the same colour

    Pr = E.S1.C1r = E.S2.C2r

    Pr = E1.S1.C1r = E2.S2.C1r

    This is the scientific definition of metamerism

    Now the situations I have shown you are drawn from the same mathematics.

    The first example I showed with the ferns showed two substances that looked the same on one camera but different on another but on another camera they looked the same.

    This would be because of the interaction of the substance spectral reflectance with the sensor absorption spectrum (this is a simplification as mentioned previously).

    Now the main issue with this is that if my eye saw these two substances as different and I wanted to represent this in my photograph, I could not..

    The second example showed a colour calibrated image using an IT8 target but where the cobalt blues and powder blues had shifted towards magenta to some extent on different sensors.

    This isn't much different than the problems discussed in this paper about accurate painting reproduction.

    http://www.rmimaging.com/information...hotography.pdf

    This exceptionally 'illuminating' paper explains the sorts of problems a photographer needs to be aware of when trying to reproduce images that match the typical human tristimulus response. It's well worth a read and I would recommend paying particular attention to the part about CCD spectral response and colour filters.

    The paper also explains why very strong infra red filters are not installed in cameras by default..

    Tim

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by timparkin View Post
    You really should familiarise yourself with the scientific literature, not just read wikipedia.

    http://www.cis.rit.edu/mcsl/research/PDFs/Spec_Met.pdf

    This is nothing to do with colour profiles, it's to do with the interaction of the emission spectra of the object being photographed and the transmission spectra of both the colour filter array and the silicon sensor beneath.
    Tim, random internet searched are not going to help. But I thank you for pointing to a paper written from RIT--the place I studied color science. The paper essentially agrees with my position. Metamerism is still about color mismatch of two objects because of the change in illuminant or observer, not of why cameras produce different colors.

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    Re: H3D39 as first step to MFDB/Technical (& vs DSLR)

    Quote Originally Posted by Shashin View Post
    Tim, random internet searched are not going to help. But I thank you for pointing to a paper written from RIT--the place I studied color science. The paper essentially agrees with my position. Metamerism is still about color mismatch of two objects because of the change in illuminant or observer, not of why cameras produce different colors.
    Hardly random search as I'd already found this in the past - it's just one of the papers that demonstrates the case that you don't necessarily need a human observer (something you stated earlier). I don't see how the paper agrees with this position.

    In any case, the camera is the observer and as such you can get a colour mismatch if the cameras total spectral response changes.

    I don't know what is difficult to understand here?

    Also at one point you say

    1) "And since every camera can make a relatively accurate real color image"

    regarding number one, I think you should take a look again at some early phone cameras...

    2) "Cameras do not suffer from metamerism"

    Nothing "suffers from metamerism" - that's a nonsensical statement. two different cameras behaving as two different observers can contribute to a system that exhibits metamerism.

    3) "Metamerism is about two different materials that appear the same color under one light source, but no longer match under another."

    No - that is only one part of metamerism. For someone with a degree (or higher?) in colour science I'm surprised that you ignored the observer. I'm also surprised that later in the thread you include the observer but then say they must be human. And then later agree with a paper that suggests that observer can be a digital sensor. At least commit to a single point of view!?

    4) "It has to do with objects and human observers, not cameras. Cameras, unlike humans, have the same spectral response."

    I don't know how you can possibly say you have a qualification in colour science and say this!!! really??!?

    5) And it still come down to observing two different objects that appear to have the same color. It is not that the observer sees them as the same, but the colors match.

    You're making massive mistakes about what colour is. Colour does not exist without an observer. It is primarily a human construct but we've made approximations that allow a tristimulus approximation to colour for machine systems.

    You're also mixing up the role of a colour profile and didn't read the fact that the scenes I've been talking about that showed different colours were profiled. Hence it's not a profiling issue.

    Out of all of these points though I think you should explain your statement 4

    "Cameras, unlike humans, have the same spectral response"

    How have you come to believe this?

    Tim

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