Archived posting to the Leica Users Group, 2010/11/13
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Hi Vick (and all) > On 11/9/2010 3:52 AM, Jean Louchet wrote: >> Just to share my short experience, on my recently acquired M9, the CV >> 12mm does require vignetting correction. After some disappointment >> with coding it as the 16/18/21 (code 010000) and several other tests, >> I coded it with code 011001 (recognised as a 2.8/24 ASPH) and the >> results now look not perfect but very acceptable. Has ayone found a >> better suited code? >> I am using the same code for the CV 15mm as well. >> Jean > > Date: Tue, 9 Nov 2010 08:17:30 -0500 > From: Vick Ko <vick.ko at sympatico.ca> > > Very informative, Jean > Do you use the same code for the M8? > What method are you using? Black marker? As the M8 only uses the centre of the image provided by the lenses, the vignetting of the 12 mm and 15 mm are not very disturbing on the M8; however, a code that works on the M9 will work on the M8. The M8 will be less sensitive to using a (slightly) wrong code. I agree with other list members that vignetting is not really an issue from 50mm up on the M9 (and its equivalent 35mm on the M8) and hardly perceptible on a 35 (M9) or 28 (M8) but it is really worth coding the lens to correct vignetting for shorter focal lengths. I have never been annoyed by any colour shift on the M9 even on extreme wide-angles. All my CV lenses are the old type, L39 mount so I have to use adapters like the Voigtlander type II where metal has not been removed in front of the code sensors (unlike the type I adapters and most original Leica adapters). They are pre-engraved, so it is easy to mark them using a thin black permanent marker. A cotton with alcohol will easily remove the ink if willing to try another code. For both 12 and 15mm I use a 35/135 adapter. I have a couple of older lenses (Minolta and Leica) where I wrote directly on the mount, it works fine. My own experience on adapters: my preferred are the Voigtlanders type II, I found the Millich are well done but don't get the lens properly oriented, and the ones sold on ebay by ***sweden or ADPLO have a rough mating surface and don't have the right orientation either. Oh yes, one last thing, the excellent site http://whimster-photography.com/leica_m_lens_codes/index.html has been updated a couple of days ago and now gives the codes of the 1.4/21 and 1.4/24. I will try them with the CV12 and 15, and tell here how it works. Jean