Jump to content

M240 6 bit coding issue with Leica glass


satureyes

Recommended Posts

Advertisement (gone after registration)

Anyone else having problems with lenses showing as uncoded/code - even though they are Leica M lenses?

 

I just noticed tonight that the M240 seems very sensitive to the lens placement.

 

The 50 'lux seems to flick between uncoded and coded - there is a little more play in the lens when it's on the camera and that tiny amount is enough to make the camera think there is no coded lens on.. can't be even 1mm.

 

Doesn't happen with my other lenses (21SE and 35 'lux) - so it could be specific to the 50 'lux.

 

Anyone else had issues?

 

Can the lens mount be 'tightened' so it locks with less play and therefore won't move on the camera? It can only be half a mm as it is.. but it's a little more than other lenses I tried.

 

Could of course be due to the LED sensor or the coding in the other lenses in relation to it - but wondering where the fault lies.. camera or lens?

 

What tack do you think I should take.. is this something that can be done by Leica Mayfair and not sending to Germany? Are these tolerances something that can be altered.. which bit? The lens of the camera.. not sure what would be an 'easier' possible fix.

Link to post
Share on other sites

Try cleaning the red transparent strip that covers the lens code sensors. Sometimes grease or dirt gets on it enough to confuse the poor things. A bit of soft cloth or lens tissue slightly dampened with isopropyl alcohol or lens cleaning fluid will do the trick.

 

Don't be tempted to clean all the grease off the lens mount, though. You want a little on there so the lenses mount smoothly. Just not on the red strip.

 

--Peter

Link to post
Share on other sites

I used to have the same issue with one (brand-new and factory-coded) of my Leica M lenses on the M9. Customer Care changed the lens' bayonet mount under warranty which fixed the problem. I have not yet seen the same problem with any of my coded lenses on the M (Typ 240).

Link to post
Share on other sites

Hi - it's the chrome 50 'lux that only has this issue.. if i turn the focus ring to infinity - the 'bump' is enough to knock the lens from reading the correct coding to 'uncoded'

 

i've tried to clean the LED light panel with some lens cleaner on a cotton wool bud - doesn't seem to make any difference. It seems the tolerance is very very narrow between the lens being coded and not.

 

I wonder if it's because the 'black' bit of the coding is on the edge on the 50 'lux and is just not quite aligned with the last LED on the M - whereas the other lenses have the black coding in different zones.

 

I am hoping they can change the mount in the Leica store rather than send to solms.

Link to post
Share on other sites

I'm having the same problem with several third party Screw to M adapters. The M(240) coding sensors seem to be very sensitive to any rotational play in the mount. I don't have this problem with the M8 or M9 :(. Isn't the coding array a part where almost the complete camera has to be disassembled to gain access? I think that was the case with the M8/9.

 

It may be possible for Leica to adjust/improve the coding performance in a firmware update.

 

Bob.

Edited by gravastar
Link to post
Share on other sites

Advertisement (gone after registration)

As on my other thread, I have the same issue with my Noctilux and 75/2

 

My personal opinion is that Leica have made the white bars too wide, so any rotational play makes them register with the adjacent sensor which expects black.

 

As they are only 1.6mm wide and the gap between barely 0.5mm the amount of leeway is miniscule.

 

The white bars are filled with paint which can overlap the edges, whereas the black have a matte thin finish that is just on the base of the slot.

 

You can easily see how even 0.5mm rotational play, poor painting or misalignment can cause trouble....:rolleyes:

Link to post
Share on other sites

This is a new M lens on a new M body - there should be no reason for them not to marry up properly. None at all.

 

Where's your other thread thighslapper?

 

errr..... it's the one you have already posted on ....;)

 

looks like it's just you and me singled out for this trouble.

 

interestingly I have checked all my lenses and the older ones have no rotational play at all....

 

of those that do only my noctilux and 75/2 have a problem.

 

I have blacked the bits between the bars, either end and narrowed the white bars on the painted strips so they are 0.5mm wide ..... it still registers as 75/2 ...... but still uncoded when rotated back by a miniscule amount. Framelines are actuated in both positions so it can't be that.... the alignment of the slots appears identical to other lenses and measurements confirm this.....

 

I'm confused ....:confused:

Edited by thighslapper
Link to post
Share on other sites

Me too. Very confused.

Perhaps the led array is slightly mis aligned?

 

It's irritating that it seems to take itself uncoded by use of the focus wheel to the closest distance as it 'knocks' the lens- then back to showing as 'coded' towards infinity.

 

I was wondering if its the end most sensor that is not aligned- perhaps the template on the camera mount is that .001 of a mm out and is covering too much of the led sensor?

Link to post
Share on other sites

I'm having the same problem with several third party Screw to M adapters. ...

Bob,

 

I had the same problem with several third party adaptors including a Milich and an Amadeo until I removed the white paint from the wells since when I've had no problem. They'd worked perfectly on my M8 and M9-P previously.

 

Pete.

Link to post
Share on other sites

I don't think that the factory lines are too wide, as I have three after market (Jin) mounts on my 35/2, 50/2 and 90/2.8 which have thinner lines than the Leica mounts. All three work perfectly on my M9 and none of them work at all on the M(240). I am considering drilling out the black lines a la Novoflex but have been hoping someone here will figure it out..........sigh:confused:

Link to post
Share on other sites

I don't think that the factory lines are too wide, as I have three after market (Jin) mounts on my 35/2, 50/2 and 90/2.8 which have thinner lines than the Leica mounts. All three work perfectly on my M9 and none of them work at all on the M(240). I am considering drilling out the black lines a la Novoflex but have been hoping someone here will figure it out..........sigh:confused:

Try leaving the black in and taking the white out - it worked for me. I expect it will depend on the type of paint used and it's IR blocking properties.

 

Pete.

Link to post
Share on other sites

Pete, I tried your suggestion of removing the white paint and instead use the relective/light scattering properties of the machined pit to indicate a "1". Although it worked sometimes, it was unreliable, the slightest twist on the mount causes the code to be misread or ignored. I've noticed there is more rotational play on the third party adapters adapters than on my Leica lenses which so far work OK. Thanks for the suggestion though.

 

Bob.

  • Like 1
Link to post
Share on other sites

Pete - I don't understand your suggestion - are you saying to remove the white paint and use the chrome mount only to stand in for the white lines? I have used flat white and flat black paint in all lines. Thanks, Larry

Lary,

 

I'm only saying that's what worked for me. I suspect that the white is intended to reflect IR so that the 6-bit sensor can detect its presence and the black paint is intended to absorb IR so the 6-bit sensor detects nothing. If the white paint absorbs IR owing to its constituents then the 6-bit sensor would be confused and not recognise the code. If the absorbing white paint is scraped away to reveal bare metal then IR will be reflected as intended.

 

This is just my assumption, which only applies to codings not done by Leica.

 

Pete.

  • Like 1
Link to post
Share on other sites

OK, Pete, this sounds like a good theory --- so does anyone out there know of a make of paint that (a) will reflect infra red light well (white stripes) and (B) will absorb most of the infra red light (black stripes).

 

I have just been using flat plastic model paint. Thanks. Larry

Link to post
Share on other sites

The critical bit is not the white bits but areas that should be black registering as white....

 

the sensors are incredibly sensitive.....

 

there is more going on here than at first sight ....

 

I have sat down and drawn the various configurations and 'misaligned ' them and if anything are more confused than before....:confused:

Link to post
Share on other sites

The critical bit is not the white bits but areas that should be black registering as white....

 

the sensors are incredibly sensitive.....

 

there is more going on here than at first sight ....

 

I have sat down and drawn the various configurations and 'misaligned ' them and if anything are more confused than before....:confused:

 

It's a conspiracy.

 

Another recall?

Link to post
Share on other sites

Well.. the update is that my M and the 50 lux are on their way back to Solms.

 

Went to the Leica store - and my lens was totally fine on their M - and another lens was fine on mine.. so I decided to send them both back and let them sort it.

 

I think it will take a while. The good thing is though that the fault is repeatable easily - and at will- so hopefully the German technicians will also be able to find the fault.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...