Weird lens recognition

[jaapv]

Advertisement (gone after registration)

I just bought an Elmarit 28/2.8 11804 (from this forum, a good deal and a mint lens) and of course it responds to manual detection. But with detection on Auto it comes through as a 90 mm lens- another case of a screw in the wrong place I suppose... Not that I can see much difference between the settings, a tad less vignetting at 2.8, but nothing C1 or PS cannot handle.

[Leicaiste]

Jaap,

 

You will be in trouble if Leica modify the firmware, making the M9 reverting to Auto Detection whenever it detect a coded lens.

 

[xrogers]

I have a 90 TE that is recognized reliably by coloring one screw head with a sharpie (it is slightly recessed, so I have not had to re-marker the screw, and has been working for over three years). The 28 must have a screw in the same place. If misidentification becomes a bother, a little white-out (or white paint) should fix that.

 

Until later,

 

Clyde

[jaapv]

Jaap,

 

You will be in trouble if Leica modify the firmware, making the M9 reverting to Auto Detection whenever it detect a coded lens.

 

I'll have Will code it anyway, so no problem

[UliWer]

That's no weird lens recognition, but the new Leica-lens-for-M9-councelling-service

(LLfM9CS).

 

It recognizes a nice mint 28mm and politely suggestes a new 90mm as well, already giving you some examples in your Exif.

 

Wait a few weeks, and you'll see many recognitions of 35mm.

[adan]

It's really pretty simple - there is only one screw on uncoded lenses that lies in the area where there are coding sensors. Leica has been using the same screw-location pattern for almost ALL lenses since about 1980 (35 Summilux pre-ASPH being an exception).

 

It is always in the same place, which is identical to the location of the single black dot that codes for a 90 Tele-Elmarit Type II (thin).

 

So, absent any other spurious marks like dents, any uncoded lens will be read as a "90 f/2.8 TE" if it is read at all. (unless the camera has a burned-out IR LED, or other malfunction, as was revealed on a different thread).

 

The fact that 90 and 28 lenses share the same framelines setting is an "enabler", of course.

 

My 90 TE is uncoded, has the screw - but still needed a little encouragement with white-out and pen to become happily coded. It depends on where your grime is.