offshore Posted July 10, 2009 Share #1 Posted July 10, 2009 Advertisement (gone after registration) I finally got my CV15 mm F4.5 II and did my own experimenting with coding. My examples are all fine jpegs unaltered from the camera except to reduce them down to a downloadable size for this site. The first three are coded as the 16-18-21 WATE in that order, the fourth is coded as a 21 mm f2.8 pre ASPH and the fifth as a 21 mm F2.8 ASPH. I see severe cyan fringing on the 16&18 WATE and less on the 21 WATE. To my eye the 21 mm F2.8 ASPH gives the best rendition with the least cyan fringing and vignetting and that is what I will permanently code mine as. 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/90390-my-two-cents-on-coding-the-15-cvii/?do=findComment&comment=958868'>More sharing options...
Advertisement Posted July 10, 2009 Posted July 10, 2009 Hi offshore, Take a look here My Two Cents On Coding The 15 CVII. I'm sure you'll find what you were looking for!
leicanut2 Posted July 11, 2009 Share #2 Posted July 11, 2009 Offshore, I think I will do the same great little lens. Cheers Jan Link to post Share on other sites More sharing options...
Bo_Lorentzen Posted July 11, 2009 Share #3 Posted July 11, 2009 Offshore, Did you put a UV-IR filter on that lens.? . Link to post Share on other sites More sharing options...
offshore Posted July 11, 2009 Author Share #4 Posted July 11, 2009 Offshore, Did you put a UV-IR filter on that lens.? . No because typically I don't shoot color I shoot B&W with an IR filter. Not sure what effect a UVIR would have on cyan fringing. The color work I do has only produced the magenta cast once and it was a black lampshade made from synthetic fabric. Link to post Share on other sites More sharing options...
epand56 Posted July 11, 2009 Share #5 Posted July 11, 2009 Offshore, any experience is ok, but having this lens since a little while now, I can say that the better result with the code really depend on the situation. It is not said that a code that works outside in daylight does the same in interiors and viceversa. IMO, the WATE coding allow me to shoot in three different situations. Link to post Share on other sites More sharing options...
offshore Posted July 11, 2009 Author Share #6 Posted July 11, 2009 Offshore, any experience is ok, but having this lens since a little while now, I can say that the better result with the code really depend on the situation. It is not said that a code that works outside in daylight does the same in interiors and viceversa.IMO, the WATE coding allow me to shoot in three different situations. I've read all the prior posts regarding coding for this lens and since results do seem to vary I'm curious if the variance isn't in the camera software that does the corrections and varies from camera to camera. The resultant focal length after crop factor is adjusted is 19.95 mm technically closer to a 21 than an 18 so it's kind of in a no man's land and that is why I did my own test to see what worked best for me. The amount of vignetting on the WATE settings would transfer into severe black skies in IR that would look like a pinhole photograph and couldn't correct out very well so the smaller amount of vignetting in the 21 setting works best for me. Although it doesn't take much time I found it annoying to have to pause and make a selection of focal length, with the WATE coding, every time I turned on the camera. Given the amount of variance, and the ease of wiping off a sharpie marking and re coding the lens I would recommend that each owner do their own test to see what their preference is. Link to post Share on other sites More sharing options...
ljclark Posted July 12, 2009 Share #7 Posted July 12, 2009 Advertisement (gone after registration) Looking at the pictures on my calibrated monitor, I thought that the bottom picture tended towards blue overall. #4 seemed the most neutral in color. Running WhatColor and trying to grab some small clusters of pixels that appeared the most "white" confirmed this. (WhatColor gets past the calibration/display problem by identifying the color value of a pixel or small group of pixels. In other words, you can completely screw up your monitor settings (even reduce the monitor to B&W if the controls allow) and WhatColor will faithfully report the actual color values of the image. People sometimes get into pixel-level discussions on this forum without tools that actually define what those pixels are.) Link to post Share on other sites More sharing options...
offshore Posted July 12, 2009 Author Share #8 Posted July 12, 2009 Looking at the pictures on my calibrated monitor, I thought that the bottom picture tended towards blue overall. #4 seemed the most neutral in color. Running WhatColor and trying to grab some small clusters of pixels that appeared the most "white" confirmed this. (WhatColor gets past the calibration/display problem by identifying the color value of a pixel or small group of pixels. In other words, you can completely screw up your monitor settings (even reduce the monitor to B&W if the controls allow) and WhatColor will faithfully report the actual color values of the image. People sometimes get into pixel-level discussions on this forum without tools that actually define what those pixels are.) My monitor is calibrated as well primarily for my printing needs and what I see in the final print is what I saw on the screen so it is accurate for me. For my needs, and I think I was clear about that, coding as a 21 mm F2.8 ASPH Elmarit works for my camera and me as it will produce an accurate final print. I can also sit at my computer and look out my sliding glass doors at the scene I posted here and compare colors and the one I selected is right on, I don't think this post got into a pixel discussion it was a discussion about cyan fringing and solutions to minimize or stop it which seems to be a common problem with this lens an has been discussed at length in other posts. Link to post Share on other sites More sharing options...
henning Posted July 14, 2009 Share #9 Posted July 14, 2009 The resultant focal length after crop factor is adjusted is 19.95 mm technically closer to a 21 than an 18 so it's kind of in a no man's land and that is why I did my own test to see what worked best for me. Your preferences in tones and vignetting and the coding that helps you get there are certainly up to you, but your math doesn't have anything to do with it. :-) 15mm is 15mm and that is in Leica's terms closest to 16mm WATE coding. Crop has nothing to do with it, as all Leica M lenses are cropped. I will get a 15vII, and have been using the original since it came out. When I got the M8, I put a filter on it and coded it for 16 WATE. It has worked well on both my M8's. I don't like the tonal skewing in colour or B&W that shooting without a filter produces, either indoors or out. Unless I'm shooting IR, which the M8 is certainly good at. :-) Henning Link to post Share on other sites More sharing options...
SJP Posted July 14, 2009 Share #10 Posted July 14, 2009 Just to clarify the situation there are two types of vignetting on the M8 when using wide angle lenses: 1) the cyan corners (color vignetting), this only depends on the focal length as it results from the IR filter's angular color shift 2) the intensity vignetting due to the angle the light strikes the sensor corners, this primarily depends on how close the rear lens element get to the sensor. All lens coding corrections close to 15 mm should deal with 1, but not necesarily with 2. That is where the trial and error comes in. In cornerfix apparently both these corrections are done without requiring any coding of the lens. Link to post Share on other sites More sharing options...
RobertW Posted July 14, 2009 Share #11 Posted July 14, 2009 Coded mine as a WATE. 16mm appears to minimize the cyan fringing. Not perfect but can clean up in pp most of the time. The WATE 18 & 21 mm get progressively increasing amounts of fringing.... Best Rob Link to post Share on other sites More sharing options...
offshore Posted July 14, 2009 Author Share #12 Posted July 14, 2009 Your preferences in tones and vignetting and the coding that helps you get there are certainly up to you, but your math doesn't have anything to do with it. :-) 15mm is 15mm and that is in Leica's terms closest to 16mm WATE coding. Crop has nothing to do with it, as all Leica M lenses are cropped. I will get a 15vII, and have been using the original since it came out. When I got the M8, I put a filter on it and coded it for 16 WATE. It has worked well on both my M8's. I don't like the tonal skewing in colour or B&W that shooting without a filter produces, either indoors or out. Unless I'm shooting IR, which the M8 is certainly good at. :-) Henning Henning I'm glad you brought this up because it is something I've been somewhat confused over. A 15 mm lens is designed to provide a field of view in degrees of 111 d, 77.3 v, and 100.4 h on a frame of 35 mm film, but if the cropped sensor is actually reading the field of view in degrees of a 21 mm lens which produces in degrees 91.7 d, 59.5 v, and 81.2 h does the software in the M8 correct for a 21 or a 15? And if the M8 software is designed to correct for a WATE, the widest field in degrees being 16 mm wouldn't it be just as confusing to the software to correct a 15 at 16 as it would to correct it for a 21 mm? Anyone have an explanation that a layman can understand? Link to post Share on other sites More sharing options...
ljclark Posted July 14, 2009 Share #13 Posted July 14, 2009 A 15 mm lens is designed to provide a field of view in degrees of 111 d, 77.3 v, and 100.4 h on a frame of 35 mm film, but if the cropped sensor is actually reading the field of view in degrees of a 21 mm lens which produces in degrees 91.7 d, 59.5 v, and 81.2 h does the software in the M8 correct for a 21 or a 15? And if the M8 software is designed to correct for a WATE, the widest field in degrees being 16 mm wouldn't it be just as confusing to the software to correct a 15 at 16 as it would to correct it for a 21 mm? Anyone have an explanation that a layman can understand? The M8 firmware "knows" nothing about how a particular lens covers full frame film -- why should it care?. It has been instructed to respond to the coding of a lens and whether or not there is a filter in place (which you have to set with the camera menu). The firmware actions prompted by that lens coding are based on how that particular lens behaves on the M8 sensor (both with and without a filter). A 21mm lens is a 21mm lens -- not a 28mm lens. There may be a difference between Leica lenses of the same focal length, but those are specific model characteristics. Don't try to over-think this. Link to post Share on other sites More sharing options...
offshore Posted July 14, 2009 Author Share #14 Posted July 14, 2009 The M8 firmware "knows" nothing about how a particular lens covers full frame film -- why should it care?. It has been instructed to respond to the coding of a lens and whether or not there is a filter in place (which you have to set with the camera menu). The firmware actions prompted by that lens coding are based on how that particular lens behaves on the M8 sensor (both with and without a filter). A 21mm lens is a 21mm lens -- not a 28mm lens. There may be a difference between Leica lenses of the same focal length, but those are specific model characteristics. Don't try to over-think this. At the risk of over thinking this and appearing dense since the software reacts to how a particular lens behaves on the M8 sensor then since Leica does not make a 15 mm lens, nor a code for one, why would it matter what you coded the VC at as long as it works? I'm only bringing up this issue not to convince anyone to code their lens the way I have, but because I ordered the lens and while waiting for it read the posts on coding and saw they seemed to be all over the place. Some coded as a WATE and used 16 some 18 and some 21. Some coded as an 18 mm Super Elmar and some as a 21 pre ASPH and some as a 21 ASPH. Either the lens suffers from a lack of quality control (which VC is known for) or the software in the camera varies from camera to camera as to how it reads coding. My understanding of the coding is that it also corrects edge distortion on wide angles and I can see the difference in edge distortion in images from my 21 before and after coding so how does the software accomplish that by reading the focal length of the lens or reading the equivalent focal length of the lens as it is recognized by the sensor? I'm going for a bike ride. Link to post Share on other sites More sharing options...
doubice Posted July 14, 2009 Share #15 Posted July 14, 2009 ....... Anyone have an explanation that a layman can understand? Very simple, as noted above: a 15mm lens is a 15mm lens, a 21mm lens is a 21mm lens etc etc. It does not matter what the crop factor is, because it will be the same for a 21mm Skopar and a 21mm Elmarit or 35mm Skopar and a 35mm Summicron. The coding and the firmware correct for characteristics of a particular lens, when mounted on the M8. So - a 15mm Heliar is probably going to be close in vigneting and other atributes to the 16mm focal length on the WATE (that is how mine is coded and I am happy). And the 21mm Skopar will probably benefit from coding it like a 21mm Elmarit or as a 21mm WATE. Obviously, there will be other factors at play - distance of the rear element from the sensor and natural vignetting of certain lenses. The M8 firmware and 6-bit coding take these into account when properly coded Leica lenses are used. With non-Leica lenses, certain amount of experimenting is necessary but, generally coding non-Leica lenses as their Leica focal length equivalents has worked. Best, Jan Link to post Share on other sites More sharing options...
khiromu Posted July 15, 2009 Share #16 Posted July 15, 2009 Mine is coded as WATE and usually select 16mm. To my eyes, results look fine. And I do use UV/IR filter on it. Link to post Share on other sites More sharing options...
Ecar Posted July 15, 2009 Share #17 Posted July 15, 2009 Mine is coded as WATE and usually select 16mm. To my eyes, results look fine. And I do use UV/IR filter on it. Same here, although I noticed that the new M-mount version of the CV 15 seems to be less sensitive to the focal length you select in the WATE menu than the old version with Milich adapter (both with filter, of course). I know it's the same optical components, so there should be no difference. Don't have the old one anymore, so can't do tests. Maybe it's just an impression - or a case of "good copy" vs. "bad copy"? The latter may explain why different copies of the new version react slightly differently to coding. Just a thought:confused: Link to post Share on other sites More sharing options...
offshore Posted July 16, 2009 Author Share #18 Posted July 16, 2009 Most owners of the lens (at least the ones posting here) prefer the lens coded as a WATE and use the 16 mm setting since the sensor crop factor is not relevant as to how the lens is "read" by the sensor that reads the coding so a 15 mm is a 15 mm and the closest is 16 mm. With that in mind I did a little more testing just for fun and hey I was bored today. So I set my tripod up on my patio and secured my M8 to it and used the same criteria as the original test and went a step further and retook each photo in b&w IR then, since I don't have a UV/IR in 52, I took the same scene with my Leitz 21 mm F2.8 Elmarit pre ASPH coded by Leica with a UV/IR and without. The three results will be in separate post with explanations. This post has images taken with the CV coded as a WATE, no UV/IR, F5.6 in aperture priority, hyperfocaled, opened in PS3 no alteration except cropping and sizing to post here. images are 16,18,21 in that order. What I'm still seeing is severe cyan fringing at the 16 setting less in the 18 and the best is the 21 setting. That's on my screen. Next post has the same settings in IR. 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/90390-my-two-cents-on-coding-the-15-cvii/?do=findComment&comment=964634'>More sharing options...
offshore Posted July 16, 2009 Author Share #19 Posted July 16, 2009 This post has the same camera settings except each image is -2/3 stop on exposure compensation because that's how I expose my IR, set on b&w mode in camera and I adjust them in the RAW file convertor or in channels. These files were not adjusted in raw file convertor but in channels and each was adjusted R=68, G=28, B=20 for consistency. Interestingly it appears the camera does not care much about the focal length setting when an IR filter is on front because all three are pretty close to being the same. Once again WATE 16,18,21. 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/90390-my-two-cents-on-coding-the-15-cvii/?do=findComment&comment=964636'>More sharing options...
offshore Posted July 16, 2009 Author Share #20 Posted July 16, 2009 In this last post I decided to play around a little bit and popped on my 21 mm F2.8 pre ASPH 6 bit coded by Leica. Since I don't shoot much color I wanted to see what difference if any a UV/IR made. The first image is no UV/IR lens detection off. The second is no UV/IR detection on. The third is with UV/IR lens detection off and the last UV/IR lens detection on. Interesting that the two with UV/IR lens detection on and off are similar and the two with no UV/IR lens detection on and off are similar. On my screen I see the 21 setting on the 15 CV giving the best image quality at 21 when coded as a WATE and as a 21 ASPH, the other settings have too much cyan fringing. Although the focal length setting and crop factor are technically not supposed to be a factor on my screen the setting closest to the 19.95 has the best image quality and least cyan fringing so for my lens on my camera it stays coded as a 21 ASPH. Life is all about variety and this lens seems to lend itself to that. 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/90390-my-two-cents-on-coding-the-15-cvii/?do=findComment&comment=964646'>More sharing options...
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