Archived posting to the Leica Users Group, 2010/11/13

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: [Leica] CV Ultra-wide Heliar (12mm) 6-bit coding on M9
From: jean.louchet at (Jean Louchet)
Date: Sat, 13 Nov 2010 18:54:00 +0100

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>
> 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

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
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.


Replies: Reply from Frank.Dernie at (Frank Dernie) ([Leica] CV Ultra-wide Heliar (12mm) 6-bit coding on M9)