wparsonsgisnet Posted February 26, 2007 Share #1 Posted February 26, 2007 Advertisement (gone after registration) I have noted, and commented a few times on the Forum, that I get more shadow detail with the M8 than I ever did with my M's. The first time I saw it, this chimp couldn't believe it. I was walking in Harvard Square with my new M8 and took a picture of the street after dark, at iso 1250. The shadow-covered walls positively glowed. I have speculated that this is due to the compression algorythm the M8 uses to store the 16-bits in 8 bits of space. I wonder if it has to do with the spectral response of the Kodak chip. I can tell you that the lenses I use have not changed -- I got that right the first time! Any monsters out there with the answer? tnx, Link to post Share on other sites More sharing options...
Advertisement Posted February 26, 2007 Posted February 26, 2007 Hi wparsonsgisnet, Take a look here Why does M8 gather so much light in the shadows?. I'm sure you'll find what you were looking for!
ddp Posted February 26, 2007 Share #2 Posted February 26, 2007 When you were using the film M's, how did you determine shadow detail? Were you viewing prints or chromes? Scans? That makes a big difference..... Link to post Share on other sites More sharing options...
carstenw Posted February 26, 2007 Share #3 Posted February 26, 2007 The compression algorithm can't improve matters compared to full 14-bit or 16-bit files. I think we are just witnessing the greater dynamic range of (good) digital vs. film. I do love the look I get from this camera, I must confess. Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 26, 2007 Author Share #4 Posted February 26, 2007 Dan, with film, I always exposed for shadows. I never got this detail. Never. Except for when I used Ilford XP2, indoors. The response curve of that film is such that shadows seem more luminous. Never used it outdoors, but images I have seen of that film used outdoors in sunlight shows no extra luminosity in shadows. Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 26, 2007 Author Share #5 Posted February 26, 2007 Me too Carsten. I like the detail, expecially, and am getting along with external filters just fine. I recently got steel screw-in hoods for my 24 and 35 lenses and now don't bother with lens caps. At the rate I am acquiring little extras for this single camera body, I'm glad I don't collect old cars! Link to post Share on other sites More sharing options...
rosuna Posted February 26, 2007 Share #6 Posted February 26, 2007 The last number of the LFI explains this. The 8-bits compression doesn't affect the shadows. The A/D converter is of 16bits, but only 14bits are usable (due to noise). This information is compressed non-linearly. Highlights are compressed, but shadows remain untouched. The reason of your shadows detail is in the quality of the sensor (dynamic range), lens and the A/D converter, I suppose. Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 26, 2007 Author Share #7 Posted February 26, 2007 Advertisement (gone after registration) Thanks Ruben. I used to subscribe to LFI but gave up. Maybe I'll reconsider. Link to post Share on other sites More sharing options...
rosuna Posted February 26, 2007 Share #8 Posted February 26, 2007 The actual number (February 2007) is excellent. It brings a lot of information very interesting for M8 users. Link to post Share on other sites More sharing options...
4season Posted February 26, 2007 Share #9 Posted February 26, 2007 Infrared sensitivity may also have something to do with it--call it a very real sort of "Leica glow" Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted February 26, 2007 Share #10 Posted February 26, 2007 Bill finally someone is seeing what you bought a Leica digital camera for and besides the build quality, lenses and color and all those wonderfull things . The one thing that is huge is the range these files have . There is a reason why DMR owners just sit and gloat. LOL Seriously I love to have fun but the truth is the range on these digitals is approaching MF range and frankly this is how i have been able to cheat buying a MF although I do really need one as Marc reminds me. LOL But this is a big difference between other's and i still believe that CCD's are better at this , Some engineers may prove me wrong but i always thought CCD was the better sensor for range. Link to post Share on other sites More sharing options...
robsteve Posted February 26, 2007 Share #11 Posted February 26, 2007 Infrared sensitivity may also have something to do with it--call it a very real sort of "Leica glow" Even with the IR filters on the lens, the files have the range Bill describes. Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 26, 2007 Author Share #12 Posted February 26, 2007 Hi, Guy. Thanks for the response. It may be that Marc is not really recommending that you get an MF camera. He may be expecting that someone who already has everything that Leica makes will naturally do this. I marvel at the M8. I did a portait shoot of a family on Saturday, leaving them with a CD at the end of the shoot, and they are raving about the jpg's. I've done more portrait work with this camera in 2 months than I did in the last 2 years. It's just an amazing tool. Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 26, 2007 Author Share #13 Posted February 26, 2007 Even with the IR filters on the lens, the files have the range Bill describes. Yes, I didn't specify in the beginning of the post, but I have 486 filters on all my lenses. Did I say what a great camera it is? Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 26, 2007 Author Share #14 Posted February 26, 2007 ... The one thing that is huge is the range these files have . There is a reason why DMR owners just sit and gloat. LOL. Guy, I viewed the images from the DMR, from the RD-1, and from C----n's fitted with R-Leica lenses with great anticipation while I waited for the M8 to exist. Leica images are rounder. More real. They define the word brilliant. Link to post Share on other sites More sharing options...
wparsonsgisnet Posted February 26, 2007 Author Share #15 Posted February 26, 2007 BTW, Guy, I can only stand (actually, I'm sitting) in awe of the pictures on your web site. Although, as a photog of dance, I appreciate the picture of the dancer in the air on the first page, I am even more taken by the lighting in the cockpit shot on the same page. Your lighting effects are superb. My fav, tho, is the one on page 14 of the red beacon on the yellow base with the blue background. It's magical. So, if anyone deserves to have everything that Leica has made, it's you. Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted February 26, 2007 Share #16 Posted February 26, 2007 Thanks Bill i need to rework that so bad that web site ,missing all my M8 and a lot of DMR images Link to post Share on other sites More sharing options...
rosuna Posted February 26, 2007 Share #17 Posted February 26, 2007 But this is a big difference between other's and i still believe that CCD's are better at this , Some engineers may prove me wrong but i always thought CCD was the better sensor for range. The so-called "fill factor" is the proportion of light sensitive surface of the sensors. Pixel spacing is not pixel size. Full frame transfer CCDs have near 100% fill factor values. All the sensor surface is sensitive to light. Inter-line transfer CCDs and CMOS have lower values for the fill factor, in the range of 30 to 80%, typically around 60%. Full frame transfer CCDs (like the KAF sensors) have the wider dynamic range and tonal resolution. Link to post Share on other sites More sharing options...
carstenw Posted February 26, 2007 Share #18 Posted February 26, 2007 I think "actual" means "current" in every language except English Spanish, German, French, Danish... LFI sells back issues. It has been really informative since at least early 2003. Before that it was still good, but not as good, back until around 1997, I think. Before that it was touch and go. The 8-bit raw format does lose some of the shadow detail, but not nearly as much as the highlights. A good compromise, it seems. Rubén, that is interesting information about CCD and CMOS sensors. Where can I learn more? Bill, I am very curious about your portrait work. Would you tell more? Link to post Share on other sites More sharing options...
rosuna Posted February 27, 2007 Share #19 Posted February 27, 2007 The LFI articles suggests, at the end, the possibility of 10-bit or 12-bit non-linear compressed files as better options. The sensor of the Leica and the A/D converter seems to be superb. It is a shame that a 8-bit compression is used for storing the files, even if it is of non-linear type. The argument is that "there is no practical difference". There isn't explicit information about the "fill factor" variable from manufacturers. Dalsa has serveral interesting pages at their website. Kodak had an interesting "documents repository", now dissapeared. Canon has interesting (and long, detailed) white papers about sensors, etc. The M8 has a sensor with 6.8 microns fotosites. The real size of the "cells" are very near of 6.8*6.8 squares, because the sensor is a full frame transfer CCD. The same goes for other KAF Kodak sensors (used in digital backs) or Dalsa sensors. When Canon presents a camera with 6.8 microns spacing, the "cells" are actually smaller, because the sensors are of CMOS type (they have circuits at the surface). The same goes for inter-line CCDs (typical of compact cameras). Exact data from the manufacturers are very difficult to get. Rubén Osuna Guerrero . Link to post Share on other sites More sharing options...
Riley Posted February 27, 2007 Share #20 Posted February 27, 2007 is it time to mention that some of the image processing on your pc is only 8 bit too Link to post Share on other sites More sharing options...
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