Hi, I recently bought a DR lens, the front barrel can be screw off from the rear barrel( the part that attached to the camera body ), I don't know if that is normal or not, I re insert the front part and the lens works fine. Thanks!!

-- Mitchell Li (mitchli@pacbell.net), June 07, 2002

Answers

mitch,

it is perfectly normal. the head, as it's called separates to allow it to be connected to the visoflex housing.

i find an added benefit, it allows easir=er cleaning of the rear element.

no problem, but, why do you find the need to torque your lenses, to see if they come apart?

-- steve (leitz_not_leica@hotmail.com), June 07, 2002.

Steve. Not quite right. The 50/2 Summicron can be used on the visoflex, although it will not focus to infinity. This lens was not really meant for use on the visoflex.

Leitz used to (in the early M days) produce a screw mount focussing mount for the 50/2 lenshead (either DR or rigid chrome) so that the lenshead from a bayonet mount lens could be removed and used on a SM camera. If you owned a BM lens, you could buy a SM focussing mount and use your lens on a SM camera.

BTW. There should be a serial number on the focussing mount that matches the one on the front ring.

-- Eliot (erosen@lij.edu), June 08, 2002.

"no problem, but, why do you find the need to torque your lenses, to see if they come apart?"

I have a 50/2 penultimate version and the assembly unscrewed once when I dismounted the lens holding it at the front. So I don't think you have to exerting much force once the seating of the optical unit is a bit loose.

-- rob (rob@robertappleby.com), June 08, 2002.

I heard you can use the front lens to enlarge with too.

-- Emile de Leon (knightpeople@msn.com), June 08, 2002.

Emile:

I tried my collapsible 50 on a Focomat enlarger. Looked good, but it had either pincushion or barrel distortion which was quite unaccaptable. What adapter would you use to put the 50 DR on an enlarger?

-- Mark Johnson (logical1@catholic.org), June 08, 2002.

Mark, I really don't know what kind of adapter you could use. I got this info on only using the head of the DR summicron for enlarging from someone who really knows optics.I assumed you could screw it in but I could be wrong.I never tried it. I asked him if this arrangement would yield excellent results or not and he said yes. He also mentioned that Leica makes more money(at that time) with the sale of enlarging lenses and that there is not a lot of difference here with using the DR or a regular enlarging lens.Sometime I'll try this and compare to my 50mm focotar and focotar-2.

-- Emile de Leon (knightpeople@msn.com), June 08, 2002.

Enlarger lens are design differently from camera lens, firstly, the image quality is optimized for two to three feet away from the lens. Secondly, it is flat field so that image projected on the paper is square. Camera lens have to deal with 3d real world object and is curvalinear. It will always project image to be pincusion on a piece of flat paper.

-- chi cheung (chic@intergate.bc.ca), June 09, 2002.