Wrong lens coding

[mbalmont]

Advertisement (gone after registration)

Hello there.

I just bought a second hand Leica M (Typ 240) and a Summicron 2/50mm V.

Everything seems to work fine so far.

But I noticed that the 6-bits coding of the lens is wrong.

It should be 100001.

But it is 011111, what is the Noctilux 1/50mm coding.

Looking close I noticed that it seemed to be hand-made, probably by the previous owner.

I have two questions :

1. Why on earth would he do that ? Is there an advantage?

2. Could this explain that the camera tells me that the lens is not locked, though it is?

Thank you for your answers.

[jaapv]

No, it cannot be of influence on the locking - that is obviously a mechanical problem. As for the coding, just get a couple of cans of black and white model paint and change it.

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[UliWer]

vor 4 Stunden schrieb mbalmont:

Could this explain that the camera tells me that the lens is not locked, though it is?

 It's the other way round: the lens tells the camera that it was a Noctilux and the camera says: "No you aren't and you won't cheat me."

[Anbaric]

Is this a pre-digital lens where the incorrect coding just been painted on the flange, or is this a later (or modified) lens that has recessed 'pits' for the coding, which have been altered for some reason? Either way, why anyone would give it an incorrect coding is a bit of a mystery. Maybe someone who had two lenses of this type and wanted to differentiate between them in their metadata?

Do you mean you are getting an error message on the screen, or is the lens not physically locking into place? I think there's a 6-bit coding error message that says something like a lens is 'not attached', which you can get when (e.g.) you try to use an LTM lens with some M adapters in live view mode:

Maybe the amateur coding on your lens is being misread by the sensor, which is confusing the camera? I think some of these issues were fixed in later firmware versions, so you may want to update if this is a similar problem, but what you really need is a correctly coded lens.

[RexGig0]

4 hours ago, mbalmont said:

Hello there.

I just bought a second hand Leica M (Typ 240) and a Summicron 2/50mm V.

Everything seems to work fine so far.

1. Why on earth would he do that ? Is there an advantage?

Thank you for your answers.

The previous owner(s) may have tested the lens, and found that coding it as a Noctilux worked “fine,” for his/her/their specific creative needs/desires, on the camera(s) used by the previous owner(s). Keep in mind that some shooters do not want vignetting to be totally corrected. Baking-in the Noctilux correction may have provided a desired effect, at least with a specific camera body.

Or, of course, the incorrect coding could have been a mistake. 

[Maarten]

Could it be that the original non-coded flange has been replaced by a third party flange with 6-bit pits?

That doesn’t explain the coding, but could explain the error message for example when the flange is not selecting the 50/75 mm frame lines. In that case the camera cannot match the 6-bit code with the apparent focal length of the lens.
 

[250swb]

Advertisement (gone after registration)

12 hours ago, mbalmont said:

Hello there.

 

2. Could this explain that the camera tells me that the lens is not locked, though it is?

 

Have you let the lens just snap into position? Don't keep you finger on the lens release button as you mount it, that can cause the lens to go over centre/over rotate in the mount and the frame lines and coding will be off. As for the coding everybody is entitled to try different codes depending on the look they are after, the Leica codes are supposed to be 'ideal' but that doesn't stop anybody adjusting them.  So if the correct framelines are projected in the viewfinder it then just means somebody tried a different code, or they could have just got it wrong, who knows?

[mbalmont]

Thank your for all your answers.

About the first question, I guess the previous user was looking for some advantages regarding vignetting. Which I can't understand since the Summicron 2/50mm V is so good. And anyway I corrected the problem using manual detection.

Regarding the LiveView issue, looking more closely I noticed that the painting is poorly done (special thanks to Anbaric). This seems to explain the problem. I will do things correctly one of this days. But for the time being, I didn't buy a telemetric Leica to use LiveView, which I don't really like anyway, or make videos.

I'll let you kow if the model paint works.

Thank You again.

Michel