wslam Posted November 27, 2009 Share #1 Posted November 27, 2009 Advertisement (gone after registration) When I mount my crons on the M9, the aperture value is recorded. However, with my 50 Noct (0.95), it is not. Is this normal? Link to post Share on other sites More sharing options...
Advertisement Posted November 27, 2009 Posted November 27, 2009 Hi wslam, Take a look here M9, 50 Noct, EXIF. I'm sure you'll find what you were looking for!
chrism Posted November 27, 2009 Share #2 Posted November 27, 2009 That's strange - the estimated aperture should show up when a lens is coded, provided the camera was set to Lens Detect - Auto, and provided you used a raw convertor that can read that data (C1, LR3beta). Chris Link to post Share on other sites More sharing options...
wslam Posted November 27, 2009 Author Share #3 Posted November 27, 2009 Hi Chris, Ok, here's the problem. Of 16 photos I took tonight with the 50 Noct, only 5 of them has the aperture information recorded. 3 of these 5 photos were shot at f0/95 but LR reads f1 instead. 11 of them says Unknown Aperture. I hate to send either of these items to Leica for repair... Link to post Share on other sites More sharing options...
mby Posted November 27, 2009 Share #4 Posted November 27, 2009 I wasn't aware that the new .95 Nocti is already incorporated into current firmware 1.002, maybe you want to check? Best regards, Michael Link to post Share on other sites More sharing options...
wslam Posted November 27, 2009 Author Share #5 Posted November 27, 2009 Hi Michael, When I mount the 50 Noct onto the M9, and then press Info, Lens does show up 50/0.95. Is that what you mean by it being incorporated by the firmware? ws Link to post Share on other sites More sharing options...
sandymc Posted November 27, 2009 Share #6 Posted November 27, 2009 I've seen this problem too, and it was with a Nocti, although up till I saw this post I hadn't actually associated the problem with the Nocti; I though it was just random. What happens is that the field is there in the EXIF data, but is set to zero, so get ignored by raw converters. Probably a bug in the M9 firmware. Sandy Link to post Share on other sites More sharing options...
adan Posted November 27, 2009 Share #7 Posted November 27, 2009 Advertisement (gone after registration) At best the M digitals estimate the shooting aperture - usually within about 1.5 stops - by comparing the scene brightness (the little blue sensor above the red Leica dot on the camera) to the metered scene brightness off the shutter blades. I have shots taken with a 35 f/1.4 @ f/1.4 where the estimated aperture gets listed in EXIF as anything from f/2 to f/1.5 to f/1 to "--" (which I presume means an estimated aperture larger than f/1 or f/0.95, thus undefined or "unknown.") Since there is no hard-wired circuitry actually reading the shooting aperture - as there is in the contacts of an SLR lens - there really isn't anything to repair. I would guess the variation is mostly due to the blue sensor having a fixed field of view of the scene which is likely not the same as the metering area (the gray shutter blades as seen by the camera's internal metering cell) with any particular lens. The blue sensor likely reads parts of the scene that are not included in the metering area, so that if the center of the image is brighter or darker than the overall scene (spotlit stage performer on dark stage, person against light wall, etc.) the blue sensor will see all that dark or light background and the estimate is going to be a WAG. It is nice that Adobe and Leica now reveal the guessed aperture - but it was never intended as rock-solid EXIF information, just as a rough way for the camera to adjust the vignetting corrections it applies for "probably close to wide open" and "probably stopped way down" shots. -------------------- The "new" Nocti is a year old - I doubt Leica forgot to include a lens announced in 2008 in firmware created in 2009. Link to post Share on other sites More sharing options...
Ario Arioldi Posted November 27, 2009 Share #8 Posted November 27, 2009 There is nothing to send to Leica to repair. The problem, if any, is with LR and in how the Camera Maker data are decoded. The aperture value you see in LR is an extimate, calculated using the TTL EV value and the blue dot EV value from the exif. The lens itself does not transmit any aperture value to the camera or to LR. Cheers, Ario Link to post Share on other sites More sharing options...
wslam Posted November 27, 2009 Author Share #9 Posted November 27, 2009 Thank you Andy and Adan for the clarification. I am aware of the lack of electronic communication between the lens and the camera, and I was indeed curious how it got the aperture values with my crons. The 'values' guessed were very closed to being accurate. Is there a way to DISABLE this guessing? Frankly, I rather get all "-" then an aperture value that may, or may not be correct. The estimate could be quite off.. e.g., here is a pic from dinner, M9, 50/0.95 at 0.95, ISO1000, the EXIF reads f4.0, but it was shot at f0.95. (Sorry EXIF is not intact in the image... some smugmug quirks...) Link to post Share on other sites More sharing options...
mby Posted November 28, 2009 Share #10 Posted November 28, 2009 Hi Michael,When I mount the 50 Noct onto the M9, and then press Info, Lens does show up 50/0.95. Is that what you mean by it being incorporated by the firmware? ws Yep, so it looks like it's properly included in the internal lookup table. Best regards, Michael Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.