Where is there a "reference" when doing Image Comparisons?

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I very much enjoy the Image Comparsion feature this website offers, but there is one piece of the puzzle missing for me. Although I can compare camera images to each other all day long, I have no point of reference. A listing for the "Test Box", for example, showing in TRUE colors (perhaps the same "Test Box" images reproduced by something other than a digital camera) so I may get a better idea of which digital camera comes closest to color accuracy. I noticed on the Outdoor Images the same flowers appear blue from some cameras and purple from others. As I have no way of knowing which color the real flowers were, some sort of a reference standard for comparison would be most helpful.

-- anonymous (tanfgirl@netzero.net), September 17, 1999

Answers

I remember seeing somewhere on the website an analysis of scanned film vs digital where they had a picture of the musicians from a scanner. This should provide a reasonable reference.

-- Dennis Pereira (dpereira@ultranet.com), September 17, 1999.

Indeed, a difficult question: Sort of a "what is reality" question. A basic problem is that if I make it look right on my monitor, it might not on yours. Of course, granted that even reasonable differences in monitors won't make flesh tones green, but you get the idea. The suggestion of checking the scanner images is a good one, at least for the Musicians shot, and possibly the Davebox target. - Try the review of the HP S20 scanner, that one probably has the colors that looked the closest to "real" on my screen.

You're right, we should probably take a shot of the "outdoor portrait" picture with some nice, neutral slide film, scan it, and adjust the resulting image so it looks as good as possible on-screen, then post that as a "reference image." - We actually got close to doing that once, during our scanner testing: We needed some test targets on 120- sized film (6x7cm) to test the Dimage Scan Multi form Minolta. Wanting really fine-grained film, I went out and bought a bunch of Fuji Velvia. What a mistake! The ultra-saturated colors on the Velvia produced a very bizarre rendition of the skin tones, and overbright colors everywhere else. Oh well. Suggestion taken though, and the next time we're shooting that scene, I'll some slide film (probably a couple of different types) in our 35mm cameras and see what we can do.

(BTW, the flowers are a pretty good light-navy blue. The purple tinge is a definite aberration many cameras seem to have. Long explanation behind it about color-matching functions and metamerism, but bottom line is it's a nice flag for whether a given camera might have problems with certain clothing dyes...)

-- Dave Etchells (editor@imaging-resource.com), September 19, 1999.


Dave:

Thank you very much for your prompt response. I have been doing so much digital camera research that I'm starting to go blind!

I have delayed purchasing one thus far because I just couldn't accept the grainy photos that the earlier models seemed to exhibit. I intend to do everything from macro to web image posting to photo enlarging, and I want the best semi-pro camera I can afford. I am very impressed by the macro (micro?) shot taken by the CoolPix 950, but on the other hand, Kodak's 290 is due for release next month (no MSRP listed as of this date on Kodak's website). Any suggestions you may offer would be most appeciated. I know you'll get a good laugh out of this, but I haven't purchased a camera of any type since my purchase of a Minolta XK in the 1970's!

Thanks again for everything,

-- (tanfgirl@netzero.net), September 20, 1999.


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