Artichoke Posted January 31, 2009 Share #21  Posted January 31, 2009 Advertisement (gone after registration) My M8 already has an inferiority complex, cant handle all the new toys on the block, this stuff has sent it into a deep depression. Jeff does DXO support the M8's raw files? what were the methods they used for their rankings? elementary principles of critical thinking warn of the dangers inherent in placing too much stock in such evaluations I have used cameras that DXO ranked much higher than the M8 & I know how they compare for what I do I am presently learning the new top rated camera from DXO, the Nikon D3X, which does produce a remarkably fine file, but I look forward to using my M8 more as I get closer to mastering my new camera too many are seduced by folks in white coats spouting scientific sounding gibberish John Dewey where are you now that we need you? Link to post Share on other sites More sharing options...
Advertisement Posted January 31, 2009 Posted January 31, 2009 Hi Artichoke, Take a look here DXO sensor mark--how is it done?. I'm sure you'll find what you were looking for!
pgk Posted January 31, 2009 Share #22 Â Posted January 31, 2009 Does the word 'photophile' exist yet? If not why not? I think it would be a useful (and not derogatory) description of some photographic equipment users who are very interested in the technology, as opposed to absolute application, of their equipment. Tell me I'm wrong. Link to post Share on other sites More sharing options...
ho_co Posted February 1, 2009 Share #23 Â Posted February 1, 2009 Maybe "geek"? Â "Photophile" sounds too much as if it denotes an interest in photography. Â Anyone know Greek for "equipment"? Something like "equipophile," but from Greek instead of Latin? Link to post Share on other sites More sharing options...
sreidvt Posted February 1, 2009 Share #24 Â Posted February 1, 2009 Sean..., Geez, it sounds like you're trying to keep Howard on a pretty short leash. Â A leash? I don't think I understand your comment. I was trying to understand what Howard was confused by. Link to post Share on other sites More sharing options...
barjohn Posted February 1, 2009 Share #25  Posted February 1, 2009 I thought I understood better their methodology but something appears to be wrong when one compares the RAW images taken under controlled conditions on DPReview.  Attached are enlarged crops from their G1 vs E520 RAW, both at ISO 100 followed by the M8 vs 5D RAW comparison. See what you think. Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/75665-dxo-sensor-mark-how-is-it-done/?do=findComment&comment=796660'>More sharing options...
SJP Posted February 1, 2009 Share #26  Posted February 1, 2009 I thought I understood better their methodology but something appears to be wrong when one compares the RAW images taken under controlled conditions on DPReview. Attached are enlarged crops from their G1 vs E520 RAW, both at ISO 100 followed by the M8 vs 5D RAW comparison. See what you think. After your post I am suffering from meta-confusion, as I do not understand the DXO methodology but also do not see what your comparison is (supposed to be) showing. The lower two pics look better than the upper two in terms of resolution & contrast, but I am not sure a crop tells all that much anyhow. Full frame and crop might be a different matter. Link to post Share on other sites More sharing options...
barjohn Posted February 1, 2009 Share #27 Â Posted February 1, 2009 Advertisement (gone after registration) Look at the gold coins on the Martini & Rossi label. There are horizontal lines on the image. Then compare and tell me what you see in terms of which images are resolving and showing those lines most clearly. Look at the writing on the batteries. Note the effect of the weak AA filter on the G1 and no AA filter on the M8 in terms of creating moire around certain Japanese letters. Â My point is that DXO rated the sensor on the E520 above the G1 yet when looking at the images it clearly is not the equal of the G1. The 5D is slightly better than the M8 but it is a slim margin other than the lack of moire. In fact the G1 comes closest to the 5D in this comparison. Link to post Share on other sites More sharing options...
stevelap Posted February 1, 2009 Share #28  Posted February 1, 2009 Look at the gold coins on the Martini & Rossi label. There are horizontal lines on the image. Then compare and tell me what you see in terms of which images are resolving and showing those lines most clearly. Look at the writing on the batteries. Note the effect of the weak AA filter on the G1 and no AA filter on the M8 in terms of creating moire around certain Japanese letters. My point is that DXO rated the sensor on the E520 above the G1 yet when looking at the images it clearly is not the equal of the G1. The 5D is slightly better than the M8 but it is a slim margin other than the lack of moire. In fact the G1 comes closest to the 5D in this comparison. As far as DXO are concerned, we simply have to remember that their methodology is a technical lab test of the sensor only, sans lens. Very interesting and useful for some, irrelevant for others.  Once you stick any particular lens onto any particular camera, all bets are off re comparing IQ from the resulting images with the DXO Mark rankings. Link to post Share on other sites More sharing options...
barjohn Posted February 2, 2009 Share #29  Posted February 2, 2009 By the way DPReview used the same Zuiko 50mm F2 lens on both the G1 and the E520 so I think it is fair to eliminate the lens. They used the following conversion process for both: For a (more) level playing field for comparison we also shot our studio scene in RAW mode with each camera and converted it using Adobe Camera RAW. Because Adobe Camera RAW applies different levels of sharpening to different cameras (this confirmed) we had to use the following workflow for these conversions:  Load RAW file into Adobe Camera RAW (Auto mode disabled)Set Sharpness to 0 (all other settings default) Open file to Photoshop Apply an Unsharp mask: 80%, Radius 1.0, Threshold 0 Save as a TIFF (for cropping) and as a JPEG quality 11 for download This is our standard studio scene comparison shot. Lighting: daylight simulation, >98% CRI. Crops are 100%. Ambient temperature was approximately 22°C (~72°F).  They don't specify the lenses used on the M8 vs 5D but I think it is safe to presume they used primes for both. Link to post Share on other sites More sharing options...
imported_reinierv Posted February 2, 2009 Share #30  Posted February 2, 2009 my M8 to catch more rain  that is a very bad idea Link to post Share on other sites More sharing options...
carstenw Posted February 2, 2009 Share #31 Â Posted February 2, 2009 DXO has a "sensormark" that puts one measure to sensors of vastly different sizes. If 5D FF is 100% area, then Leica M8 is 56% and G1 is 25%. But somehow they stop from throwing the medium format in. Â Using the scores you posted here (overall, colour depth, DR, ISO) (5D: 71, 88, 74, 54; M8: 59, 81, 75, 33; G1: 53, 81, 69, 18), and solving the three equations for the three variables, one comes up with the following weights: Â Colour depth: 55% Dynamic range: 2.5% ISO performance: 39% Â Note that they don't even add up to 100%. I would say that DxO is not basing the final score on just a linear combination of these three scores, since the weights arrived at are simply nonsensical. There must be something else factored into their combined score. Â For the record, although I do care with respect to choosing lenses and such, I couldn't care less what my sensor size is when it comes to comparing image quality. I think that is is perfectly fair to compare compact camera to medium format digital image quality. In the end, what comes out is an image, and what camera was used is irrelevant, except in so far as the camera choice impacts image quality. I think comparing the G1 to the M8 and to the 5D is a perfectly valid comparison. You want to know what a print is going to look like on the wall, not what sensor size was used to capture it. I think it is useful to know that I can get, say, an extra 21% image quality in the high ISO range by going from M8 to 5D. I don't know if that number is really reliable, but in principle I find the information useful. Â Having said that, I am not very impressed by the DxO scores so far. I find that they don't correlate well at all to my subjective impressions. Additionally, since they are lens-less scores, it cannot tell me, for example, that most of Canon's lens lineup suffers from CA, or that Leica's doesn't. That is also an important factor in choosing a system. Link to post Share on other sites More sharing options...
ho_co Posted February 4, 2009 Share #32 Â Posted February 4, 2009 In case you haven't seen it, Michael Reichmann has taken up this same conundrum at Eyes vs. Numbers. Link to post Share on other sites More sharing options...
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