Sekander Posted September 17, 2014 Share #1 Posted September 17, 2014 Advertisement (gone after registration) My lens is only 18 days old and I have observed the following: ** 1) Up to now, when I use the Noctilux fully open I have not been able to record from my photos Exif data at 0.95 even though the diaphragm is wide open. At most I get F values of magic value 1.0 *or 1.2 while the lens is at maximal aperture. Is this normal? Exposure metering/calibration issue? 2) There is a click-stop position of the aperture setting ring which is spot on in front of the 0.95 index (white dot) for diaphragm setting and another position which is the extreme click-stop position where the 0.95 label is slightly towards the right of the white dot. I am not quite sure whether the extreme click-stop position is normal. In both cases, I am unable to get photos at 0.95 while looking at Exif data. At most, I get 1.0 values at wide open aperture. Do you guys have any idea whether this is ok. Some kind of glitch? Am just wondering... Am using the latest M typ 240 firmware 2.0.1.5 and Lightroom 5.6 Thanks Quote Link to post Share on other sites More sharing options...
Advertisement Posted September 17, 2014 Posted September 17, 2014 Hi Sekander, Take a look here Noctilux @full aperture *:: is Lightroom Exif data of 0.95 recorded as 0.95 or 1.0!?. I'm sure you'll find what you were looking for!
k-hawinkler Posted September 17, 2014 Share #2 Posted September 17, 2014 (edited) Welcome to the forum! Yes, it's normal. The recorded f stop number is an estimate by the camera. There is no electronic communication from the lens to the camera. Edited September 17, 2014 by k-hawinkler 3 Quote Link to post Share on other sites More sharing options...
FlashGordonPhotography Posted September 17, 2014 Share #3 Posted September 17, 2014 Leica lenses do not transmit any exif data to the camera body during exposure, except for focal length via the 6 bit code. The aperture value in exif is from a small sensor above the lens mount and is a guess at best and often not what you set on the lens. Filters are also not taken into account so things can and will get more "interesting" with exif. If you really need it to be accurate there are programs to change exif data manually. It's just part of the fun of owning a digital Leica. edit: beaten by K-H :-) Gordon 4 Quote Link to post Share on other sites More sharing options...
Sekander Posted September 17, 2014 Author Share #4 Posted September 17, 2014 Thanks K-h & Flash Gordon, cool to know and definitely not an issue for me anymore. Guess I'll have better dreams tonite - knowing this. 1 Quote Link to post Share on other sites More sharing options...
k-hawinkler Posted September 17, 2014 Share #5 Posted September 17, 2014 Sleep well! Quote Link to post Share on other sites More sharing options...
indergaard Posted September 17, 2014 Share #6 Posted September 17, 2014 Completely normal. All my 0.95 shots are detected as 1.0 if they are correctly detected. Some are detected as f/1.4, f/2, f/2.8 and so on as well.. It's all approximations made by the electronics as there is no way for the lens to pass correct aperture information to the camera body. So ignore the detected aperture values, cause they basically mean nothing. 1 Quote Link to post Share on other sites More sharing options...
Michael Geschlecht Posted September 17, 2014 Share #7 Posted September 17, 2014 Advertisement (gone after registration) Hello Sekander, Welcome to the Forum. An interesting question. The difference between a lens opening of F1.0 & F0.95 is 1/7 of a stop. When film speeds were being standardized & represented with numbers: One of the systems that was developed was for Deutche Industrie Norm. The film speed numbers using this system are acompanied by the acronym DIN. DIN numbers are a logarithmic progression with each succeeding number representing a 1/3 of a stop increase in film sensitivity . Example: A film which is rated at DIN 24 (Equivalent to today's ISO 200) is 1 stop faster than a film rated at DIN 21 (Equivalent to today's ISO 100). The reason for choosing 1/3 of a stop as the dividing line was that the average person viewing different negatives taken of the same subject at different exposures required a minimum of 1/3 of a stop difference in exposure to see a detectable difference in 2 different negatives. Best Regards, Michael 2 Quote Link to post Share on other sites More sharing options...
Herr Barnack Posted September 18, 2014 Share #8 Posted September 18, 2014 Welcome to the forum!Yes, it's normal. The recorded f stop number is an estimate by the camera. There is no electronic communication from the lens to the camera. I have been wondering why my M240 thinks my pre-ASPH 50mm Summilux is set at f/1.6 or f/1.7 when I m shooting wide open at f/1.4... 2 Quote Link to post Share on other sites More sharing options...
Sekander Posted September 18, 2014 Author Share #9 Posted September 18, 2014 Completely normal. All my 0.95 shots are detected as 1.0 if they are correctly detected. Some are detected as f/1.4, f/2, f/2.8 and so on as well.. It's all approximations made by the electronics as there is no way for the lens to pass correct aperture information to the camera body. So ignore the detected aperture values, cause they basically mean nothing. That's exactly what's going on. Thank you Indergaard. Good advice! Thus instead of getting excited about Exif data exposure parameters, I may want to concentrate more on Pre-Treatment. Cheers, Sekander 1 Quote Link to post Share on other sites More sharing options...
Sekander Posted September 18, 2014 Author Share #10 Posted September 18, 2014 Hello Sekander, Welcome to the Forum. An interesting question. The difference between a lens opening of F1.0 & F0.95 is 1/7 of a stop. When film speeds were being standardized & represented with numbers: One of the systems that was developed was for Deutche Industrie Norm. The film speed numbers using this system are acompanied by the acronym DIN. DIN numbers are a logarithmic progression with each succeeding number representing a 1/3 of a stop increase in film sensitivity . Example: A film which is rated at DIN 24 (Equivalent to today's ISO 200) is 1 stop faster than a film rated at DIN 21 (Equivalent to today's ISO 100). The reason for choosing 1/3 of a stop as the dividing line was that the average person viewing different negatives taken of the same subject at different exposures required a minimum of 1/3 of a stop difference in exposure to see a detectable difference in 2 different negatives. Best Regards, Michael Hello Michael, Thank you for taking the time to provide a captivating answer. So that's neat to know:: Wow : 1/7 of a stop! When comparing F1.0 & F0.95, the 1/7 stop would appear to be barely noticeable/"translatable for a healthy human eye(maybe not a falcon's)" in terms of shutter speed repercussions. Correct me if I misunderstood. So, in this lens the available click-stops are F0.95 - F1.2 - F1.4... etc. and the stop difference implemented by Leica is a 1/2 stop between each? For more details, I guess I'll have to delve into Erwin Putts' publications - according to Thorsten. Years back when I started photography - I became familiar with the DIN / ASA nomenclature - At the time, I would have been pretty happy to get the explanation you provide in the last paragraph. So thanks again. I guess this piece of knowledge is not necessarily anchored in the minds of many of us! The 1/3 stop increment / decrement is well implemented by the 3 click-stops of the aperture setting ring for instance in Carl Zeiss lenses - which is very practical indeed. Best regards, Sekander 1 Quote Link to post Share on other sites More sharing options...
ninicholas Posted September 18, 2014 Share #11 Posted September 18, 2014 perhaps, the estimation is correct, there is no 0.95 in existence, just a myth or a number engraved on the aperture ring. Quote Link to post Share on other sites More sharing options...
k-hawinkler Posted September 18, 2014 Share #12 Posted September 18, 2014 perhaps, the estimation is correct, there is no 0.95 in existence, just a myth or a number engraved on the aperture ring. :D Quote Link to post Share on other sites More sharing options...
mjh Posted September 19, 2014 Share #13 Posted September 19, 2014 perhaps, the estimation is correct, there is no 0.95 in existence, just a myth or a number engraved on the aperture ring. That must have been what the designers of the Exif standard thought as there is no way one could represent f0.95 – or indeed any f-stop value < 1.0 – in the Exif metadata. The standard doesn’t allow it and although it has gone through many revisions, this restriction has never been lifted. 2 Quote Link to post Share on other sites More sharing options...
DickieT Posted July 21, 2016 Share #14 Posted July 21, 2016 Bringing this back to life this thread as I picked up a mint f1.0 (78-82) Nocti and it has the same pre-f1 and post f16 click-stop positions that do open/close the aperture just a tiny bit. None of this gets recorded properly with LR of course. When I took off the cap for the first time, I almost unscrewed the lens in 2, but I understand that's normal too ? Thanks! Dick Quote Link to post Share on other sites More sharing options...
IWC Doppel Posted July 21, 2016 Share #15 Posted July 21, 2016 Is your lend a built I hood model ? Quote Link to post Share on other sites More sharing options...
DickieT Posted July 22, 2016 Share #16 Posted July 22, 2016 No - it has 2 small steel pins on the side on which you push/slide the lens cap - bajonet style.. Quote Link to post Share on other sites More sharing options...
Surge Posted March 26, 2017 Share #17 Posted March 26, 2017 So it seems like many Noctilux aperture rings do move slightly past the end of the range (f/0.95 / f/16), correct? Quote Link to post Share on other sites More sharing options...
adli Posted March 26, 2017 Share #18 Posted March 26, 2017 I assume this kind of questions is why Leica removed aperture from the exif data on the M10 1 Quote Link to post Share on other sites More sharing options...
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