Lode Posted November 19, 2006 Share #1 Posted November 19, 2006 Advertisement (gone after registration) A member of the RFForum did a (maybe) interesting test concerning the magenta issue in Epson RD-1, Nikon D1x and Sony VSC-1 cameras. http://www.underexposure.com/irtest Lode Link to post Share on other sites More sharing options...
Advertisement Posted November 19, 2006 Posted November 19, 2006 Hi Lode, Take a look here Do Epson, Nikon and Sony have also a magenta problem? . I'm sure you'll find what you were looking for!
adan Posted November 19, 2006 Share #2 Posted November 19, 2006 IR sensitivity is inherent in silicon image capture (which, in addition to noise, is why the Hubble Space Telescope sensor is cooled with liquid something-or-other (helium, nitrogen?) That's a nice sampling. Leica has a tough nut to crack to deal with IR while also not fuzzing or cyaning the corners of images made with M lenses. It will be interesting to see how they plan to approach it on Monday. Link to post Share on other sites More sharing options...
marknorton Posted November 19, 2006 Share #3 Posted November 19, 2006 It will indeed. Right now, the apparent solutions to high quality images with M lenses on a digital sensor give you magenta, cyan or fuzz. Pick your poison! Link to post Share on other sites More sharing options...
aj37 Posted November 19, 2006 Share #4 Posted November 19, 2006 A member of the RFForum did a (maybe) interesting test concerning the magenta issue in Epson RD-1, Nikon D1x and Sony VSC-1 cameras. The R-D 1 definitely has some IR sensitivity (as shown in the test you linked) but its response to IR is less obtrusive and not as easy to provoke. I suspect this is because while it shows a response to some IR radiation, it is not responsive to as wide a section of the IR spectrum as the M8 is. After I read about this problem with the M8, I realized I had seen it occasionally in some R-D 1 shots -- but never noticed it at the time because the effect was subtle, and I had just assumed that it was just a slight sheen in the fabric or a slight color cast in the lighting. Link to post Share on other sites More sharing options...
JonasYip Posted November 19, 2006 Share #5 Posted November 19, 2006 That was my test from a while back (well, a week ago anyway). I did not have an M8 to compare so I was just guessing that the M8 perhaps was even more IR sensitive. Since then several other people have done similar but better tests. Here's one that compares an M8 and RD-1, along with a D200 and D2h, and also shows results with a Hot Mirror filter: Infrared filtration examples j Link to post Share on other sites More sharing options...
lct Posted November 19, 2006 Share #6 Posted November 19, 2006 Very interesting Jonas thanks. What's the actual colour of the blanket under the lens? Guess you've answered somewhere already but i can't seem to retrieve your post sorry. Link to post Share on other sites More sharing options...
markedavison Posted November 19, 2006 Share #7 Posted November 19, 2006 Advertisement (gone after registration) The correct colors are in the Nikon D200 shot with no filter. The Nikon D200 has very little IR sensitivity. The shots taken through the IR pass filter (the Hoya R72) are taken with the same exposure, so they give an indication of the relative IR sensitivity of the cameras. Mark Davison Link to post Share on other sites More sharing options...
sean_reid Posted November 19, 2006 Share #8 Posted November 19, 2006 IR sensitivity is inherent in silicon image capture (which, in addition to noise, is why the Hubble Space Telescope sensor is cooled with liquid something-or-other (helium, nitrogen?) That's a nice sampling. Leica has a tough nut to crack to deal with IR while also not fuzzing or cyaning the corners of images made with M lenses. It will be interesting to see how they plan to approach it on Monday. Andy, Remember the reddish cast you sometimes noticed in your R-D1 files? I remember you discussing it on the old version of this forum. Turns out it was probably IR. Cheers, Sean Link to post Share on other sites More sharing options...
lct Posted November 19, 2006 Share #9 Posted November 19, 2006 The correct colors are in the Nikon D200 shot with no filter... Is it what Jonas told you Mark? Link to post Share on other sites More sharing options...
rvaubel Posted November 19, 2006 Share #10 Posted November 19, 2006 The correct colors are in the Nikon D200 shot with no filter. The Nikon D200 has very little IR sensitivity. The shots taken through the IR pass filter (the Hoya R72) are taken with the same exposure, so they give an indication of the relative IR sensitivity of the cameras. Mark Davison Mark The correct color of the blanket is green? Only the unfiltered D200 shot shows this color, is that right? Rex Link to post Share on other sites More sharing options...
lct Posted November 19, 2006 Share #11 Posted November 19, 2006 ...I realized I had seen it occasionally in some R-D 1 shots -- but never noticed it at the time because the effect was subtle, and I had just assumed that it was just a slight sheen in the fabric or a slight color cast in the lighting. Same for me, i've noticed bizarre color casts in a few occurrences (never outdoor) but they were generally easy to adjust and i thought they came from the tungsten setting of the camera. Now i don't use flash or other bright light sources indoor, perhaps it comes from that i don't know. Here the sportswear was black but the strand was black as well: http://tinyurl.com/rv7w/EPSN0389-beforeweb.jpg (R-D1 400 iso tungsten 'cron 50 @ f/2 before correction) Link to post Share on other sites More sharing options...
JonasYip Posted November 19, 2006 Share #12 Posted November 19, 2006 Is it what Jonas told you Mark? Sorry, that was actually Mark's test that I linked to as it was a more thorough comparison. I should have made that clear. So his comments on the details are (obviously) correct. Sean also has some good examples in the latest installment of his M8 reviews on his site, if you're a subscriber. I should also add that, in regards to the title of this thread, I've never really considered the RD-1's behavior a "problem". Although now looking back through many years of RD-1 and D1x shots, I can certainly find examples where I can see the effect somewhat in normal use, but none that are of major concern. The M8 examples seem more extreme. j Link to post Share on other sites More sharing options...
harmsr Posted November 19, 2006 Share #13 Posted November 19, 2006 My Nikon D200 does not. The 5D which I rented for the weekend along with the 24-70L did have a minor amount of the magenta/IR under tungsten lighting. The M8 with the IR cut filter does not have the issue, but needs a new profile to improve the colors when using the cut filter. The M8 files blow both the 5D and D200 files out of the water. I do not have personal experience except for one day with the RD-1. Others on this forum state that it does have the IR issue to a lesser degree. Best, Ray Link to post Share on other sites More sharing options...
scott kirkpatrick Posted November 19, 2006 Share #14 Posted November 19, 2006 Don't know if the Sony has a removable lens, but for the others (Nikon, Epson) it would be nice to know if they are using the same blue-green cover glass that Leica went to for the M8, only thicker. Leica talks about their decision to use a very thin cover glass as having the side effect of allowing more IR. The Kodak spec says that the M8's 0.5mm cover glass has anti-reflective coating on both sides, and it is a special kind of glass, so it sure sounds like an absorptive filter. What do the others use? Could somebody take the lens off their RD-1, open the shutter (bulb?) and shine a desk lamp inside? A dichroic ("cut") filter is clear when you look straight in, and absorptive filter is blue green. scott Link to post Share on other sites More sharing options...
hammam Posted November 19, 2006 Share #15 Posted November 19, 2006 Go see the Nikon forum on photo.net. It seems that the D50 has some magenta aberration as well. Link to post Share on other sites More sharing options...
lct Posted November 19, 2006 Share #16 Posted November 19, 2006 ...Could somebody take the lens off their RD-1, open the shutter (bulb?) and shine a desk lamp inside? A dichroic ("cut") filter is clear when you look straight in, and absorptive filter is blue green. R-D1's chip by Sony DSC-V1 with flash (100% crop): Link to post Share on other sites More sharing options...
scott kirkpatrick Posted November 19, 2006 Share #17 Posted November 19, 2006 OK, that's one down. This picture above is an absorptive filter. Does the M8 look the same, or perhaps a little lighter in color? And the D200? I'm curious about the E-1 now (chip by Kodak in the same design philosophy), and will check. scott Link to post Share on other sites More sharing options...
waterlenz Posted November 19, 2006 Share #18 Posted November 19, 2006 That was my test from a while back (well, a week ago anyway). I did not have an M8 to compare so I was just guessing that the M8 perhaps was even more IR sensitive. Since then several other people have done similar but better tests. Here's one that compares an M8 and RD-1, along with a D200 and D2h, and also shows results with a Hot Mirror filter: Infrared filtration examples j Thanks for the post - looks like a hot mirror is not enough. I have a couple of these as well as one B+W486, the 486 has a stronger visible reflection than a hot mirror.... hmmmm Tom Link to post Share on other sites More sharing options...
Vivek Iyer Posted November 19, 2006 Share #19 Posted November 19, 2006 Here is a shot of the IR cut filter in Nikon's D70 (the blue green glass): http://www.filmlives.net/files/baaderu1_117.jpg The D200 and D2X have a double coated IR cut filter (absorptive as well as reflective). The Kodak sensor has a blue green filter (absorptive as well). However, if you look at Kodak's data, you would expect no IR sensitivity at all! Canon, on the other hand, had their IR cut filters perfected a long while ago. Link to post Share on other sites More sharing options...
rvaubel Posted November 19, 2006 Share #20 Posted November 19, 2006 Here is a shot of the IR cut filter in Nikon's D70 (the blue green glass): http://www.filmlives.net/files/baaderu1_117.jpg The D200 and D2X have a double coated IR cut filter (absorptive as well as reflective). The Kodak sensor has a blue green filter (absorptive as well). However, if you look at Kodak's data, you would expect no IR sensitivity at all! Canon, on the other hand, had their IR cut filters perfected a long while ago. Vivek Your own website reported the cutoff frequency for the absorbtive filter about a year ago!! I am having a brain hemmorage trying to remember but as I recall it was a Kodak spokesman doing the talking. I think the cutoff frequency was 780 nm. I am searching the site. Back later. But I'm sure it is a absorbtive filter Rex Link to post Share on other sites More sharing options...
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