mike prevette Posted December 1, 2006 Author Share #181 Posted December 1, 2006 Advertisement (gone after registration) That is actually my favorite 'feature' of this system. It means I can turn correction on or off with a button push. since I have an external 21 finder It doesn't affect my shooting much at all. Since most of the time I prefer vignetting it really works out. /but I agree Zeiss should fix this/ _mike Link to post Share on other sites More sharing options...
Advertisement Posted December 1, 2006 Posted December 1, 2006 Hi mike prevette, Take a look here Proof of concept regarding self coding of lenses. I'm sure you'll find what you were looking for!
marknorton Posted December 1, 2006 Share #182 Posted December 1, 2006 Mike, yes, I guess it's a situation with the Leica lenses that the recognition is normally on, use the lever to deactivate, for these Zeiss lenses, it's normally off, use the lever to activate. Link to post Share on other sites More sharing options...
mike prevette Posted December 1, 2006 Author Share #183 Posted December 1, 2006 Now how do you guys think I should code my 40mm 'cron-c, 90mm 'rokkor, 40mm VC Nokton? Link to post Share on other sites More sharing options...
rvaubel Posted December 1, 2006 Share #184 Posted December 1, 2006 Just coded my vc 15 as a 21mm f/2.8 ASPH using a thin piece of balsa. Not very useful IMHO. I see no vignette reductions. Not the right lens for its cameo. *edit- Ok did a more hardcore test and I do see an improvement in the vignetting, not a big change but it's something. _mike Mike I thought that the 15mm Heliar didn't vignette that much on the M8 even without lens coding. At least not like it does on the RD1 which was/is pretty extreme. Anyway I kinda like a little vignetting on superwides. For me, the utility of lens coding lies in getting rid of the radial cyan effect. Rex Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted December 1, 2006 Share #185 Posted December 1, 2006 I tried my Leia 24mm this morning and kept getting the 35mm . need a better template or i have the coding wrong. Tried several times, I will let Robert do it for me next week when i see him in Yosemite Link to post Share on other sites More sharing options...
frank_filippone Posted December 1, 2006 Share #186 Posted December 1, 2006 "...........The vignetting that the coding system corrects for ...." I do not think we have proof that ANYTHING happens to the image with the coded lenses, unless I missed something. Can you point me to some testing that shows there is a difference? I would like to see some image that is taken with and without the coding .,.... and see the differences... Link to post Share on other sites More sharing options...
marknorton Posted December 1, 2006 Share #187 Posted December 1, 2006 Advertisement (gone after registration) Guy, look at Carstens site, it has pictures of what the code should look like. Link to post Share on other sites More sharing options...
mike prevette Posted December 1, 2006 Author Share #188 Posted December 1, 2006 Your right Rex, it didn't vignette that bad. Compared to how it vignettes on film it's nothing, and i'm pretty sure It's a large bit better than on the RD-1. But it still does have a visible vignetting when used wide open. IMHO I agree with you the vignetting is a nice storytelling tool. 15mm 4.5 _mike Link to post Share on other sites More sharing options...
sean_reid Posted December 1, 2006 Share #189 Posted December 1, 2006 Hopefully, if this work shows an image quality improvement with the Zeiss lenses, they may be persuaded to change the lens mount to bring up the correct frame lines. It would be interesting to know if Zeiss are watching this thread. Thanks to Mike and Carsten for their great contribution. Still can't get the 16-18-21 to work... but my pen is running out so the dots may not be dense enough. Hi Mark, There's no question in my mind that the Leica corrections will greatly reduce the cyan drift for the ZM wides. Do we know yet if Leica has patented these lens codes (on the lenses themselves)? The problem with the Sharpie coding is that it will likely wear off over time. I still would like to see Leica offer the option to manually specify the lens mounted via the menu. That would be a more durable solution unless Zeiss and CV are legally allowed to code their lenses, adapters, etc. Again, it would also be useful for Leica lens owners who don't want to send those lenses in. There are also many older Leica lenses that cannot be coded. Best, Sean Link to post Share on other sites More sharing options...
marknorton Posted December 1, 2006 Share #190 Posted December 1, 2006 Frank, tests on Sean Reid's site show that the correction is real, if not especially dramatic. In the end, I think the cyan correction is going to be a bigger reason for the lens coding that vignetting correction. Link to post Share on other sites More sharing options...
sean_reid Posted December 1, 2006 Share #191 Posted December 1, 2006 Now how do you guys think I should code my 40mm 'cron-c, 90mm 'rokkor, 40mm VC Nokton? Why would you want to code a lens longer than 35 mm? It's unlikely to need it. Maybe the 40s but probably not. The cyan drift is already quite mild at 35 mm (according to my tests) and that's the upper limit that Leica has officially announced for "recommended coding". I probably wouldn't bother coding anything longer than a 35. The longer lenses, thankfully, should only need the filter. Vignetting for the 40s and up shouldn't be an issue either. In fact, it's hardly an issue with most 35s. Cheers, Sean Link to post Share on other sites More sharing options...
sean_reid Posted December 1, 2006 Share #192 Posted December 1, 2006 Mike I thought that the 15mm Heliar didn't vignette that much on the M8 even without lens coding. At least not like it does on the RD1 which was/is pretty extreme. Anyway I kinda like a little vignetting on superwides. For me, the utility of lens coding lies in getting rid of the radial cyan effect. Rex It doesn't and the cyan drift would be the big challenge. Since the CV 15 doesn't even have filter threads, I think it would be a great candidate for no filter and a Jamie profile instead. Cheers, Sean Link to post Share on other sites More sharing options...
devils-advocate Posted December 1, 2006 Share #193 Posted December 1, 2006 Do we know yet if Leica has patented these lens codes (on the lenses themselves)? Sean The problem with patenting is that the exact nature of what the patent purports to protect depends entirely on the wording of the claims in the patent application. Unless and until we see Leica's application relating to this system/process, we have no idea what they might have tried to protect (the detection system, the code itself, the process of coding the lens - and how that is described, etc., etc). Fwiw I couldn't find anything that looked like an applicable patent on either the US of EU patent sites -- it takes many months after an application is received for these even to be posted. If it calms a few minds, I'd assess the chance of Leica taking legal action against individual users (assuming they ever get a patent granted) at Z-E-R-O, for all the common-sense reasons that would likely come to every non-lawyer's mind. While a commercial infringement might be a different question,we can all relax and go back to our sharpies. Link to post Share on other sites More sharing options...
sean_reid Posted December 1, 2006 Share #194 Posted December 1, 2006 Frank, tests on Sean Reid's site show that the correction is real, if not especially dramatic. In the end, I think the cyan correction is going to be a bigger reason for the lens coding that vignetting correction. And...interestingly, even the existing correction reduces the visibility of the cyan drift on the two Leica 28s as shown in the working draft of the 28s article. I'll test the effects on the Zeiss 28 and 35 as soon as I have time. Cheers, S Link to post Share on other sites More sharing options...
mike prevette Posted December 1, 2006 Author Share #195 Posted December 1, 2006 Your right Sean, I had a momentary lapse in brain power. Today was a long one. _mike Link to post Share on other sites More sharing options...
sean_reid Posted December 1, 2006 Share #196 Posted December 1, 2006 The problem with patenting is that the exact nature of what the patent purports to protect depends entirely on the wording of the claims in the patent application. Unless and until we see Leica's application relating to this system/process, we have no idea what they might have tried to protect (the detection system, the code itself, the process of coding the lens - and how that is described, etc., etc). Fwiw I couldn't find anything that looked like an applicable patent on either the US of EU patent sites -- it takes many months after an application is received for these even to be posted. If it calms a few minds, I'd assess the chance of Leica taking legal action against individual users (assuming they ever get a patent granted) at Z-E-R-O, for all the common-sense reasons that would likely come to every non-lawyer's mind. While a commercial infringement might be a different question,we can all relax and go back to our sharpies. Hi Nick, I have no concerns about individuals using Sharpies, stickers, etc. I'm wondering if CV and Zeiss are legally allowed to code their lenses and/or adapters. Cheers, Sean Link to post Share on other sites More sharing options...
robsteve Posted December 1, 2006 Share #197 Posted December 1, 2006 And...interestingly, even the existing correction reduces the visibility of the cyan drift on the two Leica 28s as shown in the working draft of the 28s article. I'll test the effects on the Zeiss 28 and 35 as soon as I have time. Cheers, S Some of the correction for cyan drift may just be a correction for the IR filter on the sensor itself. Link to post Share on other sites More sharing options...
rvaubel Posted December 1, 2006 Share #198 Posted December 1, 2006 Your right Rex, it didn't vignette that bad. Compared to how it vignettes on film it's nothing, and i'm pretty sure It's a large bit better than on the RD-1. But it still does have a visible vignetting when used wide open. IMHO I agree with you the vignetting is a nice storytelling tool. 15mm 4.5 _mike Mike Love that bike picture! And on my monitor I don't see any discernible cyan drift or vignetting. My RD1 would have a boatload of both. Did you use a filter? Rex Link to post Share on other sites More sharing options...
marknorton Posted December 1, 2006 Share #199 Posted December 1, 2006 Sean I took a look on the US PTO site and can't find anything. Problem is, there's a long lead time - years - before a patent is granted so it's tough to know if there's a patent application in progress. I would be surprised if it were patented. Using optical codes for item recognition is widely known - I developed supermarket checkout systems for IBM in the 70's - and although the lens coding is a novel application, it's tough to think of it as a ground-breaking invention. It's the sort of thing that a day's brain-storming with a white-board would come up with. That said, I would be surprised if CV and Zeiss coded their lenses because they do not control - or can influence - what the camera does with the coding. As for Leica opening up the interface, you'll have a sense from your discussions whether this is a possibility. You've commented though on the perfectionist streak in their work and I expect making the correction generic will an anathema to them. The next step for Mike's coding work could be to look at the precision of the template - so that the black marks can be placed with 100% accuracy and the use of an epoxy ink which will be much more durable, for example: http://www.jantech.com/PDF/2PE_Data.PDF Link to post Share on other sites More sharing options...
sean_reid Posted December 1, 2006 Share #200 Posted December 1, 2006 Some of the correction for cyan drift may just be a correction for the IR filter on the sensor itself. You mean the correction that's already there in this firmware version? Possibly. Cheers, S Link to post Share on other sites More sharing options...
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