OK, I've spent the last two hours looking for a similar thread and didn't find one. I posted this question in a recent thread and didn't get an answer. Therefore, I'm starting a separate thread.

I've been to Gandy's site, and he only talks about mounting capabilities.

My question is about focus.

I've seen threads regarding "eyes" and the 35 mm lenses designed specifically for the M3, and why they wouldn't work w/o the eyeys on an M2 (because of the eye in front of the rangefinder). The Dual Range has two eyes as well.

Now, please tell me anything anyone ever wanted to know about the Dual Range and its use/non-use on the 0.72 M's (my M4 and M6).

That is: Mounting issues AND focusing issues.

-- Chris Chen (chrischen@msn.com), January 18, 2002

Answers

Also, The body's rangefinder cam has a certain range of travel. When I focus my 21, 3.4 SA close, at some point the rangefinder stops moving. Please explain how the DR long focus travel is accomodated. Was the DR made only for the M3?

-- Chris Chen (chrischen@msn.com), January 18, 2002.

Oh boy, here we go... As simply and as brief as possible:

The DR goggles are designed to work with that lens in its close focus range, and in fact can only be installed when the lens is in this mode. They are of a different design and serve a different purpose than the goggles permanently mounted on the 35 Summaron or the 135/2.8 TE. (More in a minute.) When in the DR is set to the close mode, the RF cam is re-positioned back to near infinity for normal focus, and now the goggles can be mounted. The goggles correct the parallax and RF patch for the close focus range of approximately 1 meter down to 1/2 meter, even theough the RF cam is going through its normal travel. The DR can be used on your M6 classic as is, or your M6TTL if you first remove the alignment tab on the rear of the goggles. As a precaution against RF cam damage, be sure this lens is set at infinity before mounting or removing it from the body.

By contrast, the permanent goggles on the aforementioned lenses serve slightly different purposes. On the Summaron, they bring up and correct (widen) the M3's 50mm frameline and viewfinder to equal that for the 35, since the M3 did not have 35mm framelines. On the 135/2.8, they bring up and magnify the 90 framelines and viewfinder by a factor of 1.5x thus creating more accurate focus and framing with that lens.

I'm sure I've mis-stated something, but I'm equally sure somebody with more time than me will correct my errors!

Hope this helps!

:) Cheers,

-- Jack Flesher (jbflesher@msn.com), January 18, 2002.

Thanks Jack

I've never held one of these in my mitts. I got one from ebay, and since I'm in Russia, a friend did the transaction.

I competely understand - makes sense.

However, I don't think the lens cam is repositioned; I think it ramps- up "steps-up" to allow camera cam engagement in close focus mode.

Are you located in the eastern hemisphere or you a night owl?

-- Chris Chen (chrischen@msn.com), January 18, 2002.

I'd say both statements are true. The cam does reposition to the 180 degree arc that is not in play during normal focus range. There is also a steep cam step so that even with the greater lens extension in close focus mode, the cam follower will remain in contact with the cam. The cam follower repeats its range of mechanical positions in close mode just the same as in normal mode; but this time the lenses in the optical unit cheat the range/viewfinder into proper coincidence at these closer distances.

-- Bob Fleischman (RFXMAIL@prodigy.net), January 18, 2002.

Oh thank God. Chris, Jack, Bob- Thanks for this. I too have asked this question in three different forums over the past two weeks and got bupkis in response.

I have a DR Summicron and the eyes for it, and the M3 for which is was originally intended (both bought along with a few other lenses in Hong Kong in 1960- and he only put eleven rolls of film through the camera- all of which I have- before giving it to me in 1995!). I do not have a modern M camera, but I'm thinking of springing for an M6 now while the iron is hot, before Feb.- as they say, buy on rumor, sell on fact- so I've wondered the DR would work on a new camera, with the difference in v.f. magnification and all.

Now Jack and Bob both talked about the goggled 35 Summaron- I assume the same is true for my goggled 35mm Summicron? The goggles are permanently attached to the lens ( with screws, which I could remove, I suppose) so I assume this lens will always be dedicated for my M3- yes?

Thanks again, all- I've been trying to find this info for a bit.

-- drew (swordfisher@hotmail.com), January 18, 2002.

Goggled lenses will work on any M camera, though some lenses may require maching to fit on the TTL and M5. The goggled lenses will not focus accurately without the goggles on on any M camera. The DR is not the same as the other googled lenses, it is a normally ungoggled lenses with built in close focus capabilities which only uses the goggles in the close focus range. The various SOMKY-M adapters also give close focus capabitity exactly the same as the DR for the other 50mm lenses.

-- John Collier (jbcollier@powersurfr.com), January 18, 2002.

Drew: And just to clarify John's response, the goggled 35 Summaron or Summicron bring up and modify the 50mm framelines as well as the finder magnification on any M it is installed on. As such, the lens cannot be used accurately without the goggles.

:) Cheers,

-- Jack Flesher (jbflesher@msn.com), January 18, 2002.

One of my beloved lenses is the DR 50/2. It focuses down to 0.03 of a meter. The Summichron is more versitile, focusing continuously down to 0.07 of a meter. The DR 50/2 seems fine tuned for close ups. (Speaking subjectively).

Major suggestion. Don't take that tab of to accomidate the DR 50/2 to the new M-6 TTL and Konica Hexar, as tempting as it might be. Chances are: (a) you'll lose the tab (b) forget to focus to infinity when interchanging and damage your cam.

Stick to classic M's for the DR. M-3, M-4, M-6 (old style) all accept it.

A cool combo: M-6, Rapidwinder, DR.

If you get one, you'll need to play with it before shooting. The sleeve should be turned to close focus mode with you are using it with the goggles (only used for close focus) and turned to 0.09 m. (in c.f. mode it goes from 0.09 m. to 0.03). Remove goggles by pulling. Mount. Replay goggles. In shooting 1 m to infinite. pull up on sleeve and turn counter clockwise. Don't lose the goggles.

I've probably said something confusing here but I hope you get the idea.

Using the DR 50/2 you know why it was discontinued and also why it is so well loved still by many of us.

-- Alex Shishin (shishin@pp.iij4-u.or.jp), January 18, 2002.

Interesting. I don't think I would actually remove the gogles from my 35 Summicron- I love the way it works with the viewfinder to give me a full frame 35mm view on the M3.

John C. and Jack- thanks especially for your clear input. I think I now have enough info. to let the issue rest.

-- drew (swordfisher@hotmail.com), January 19, 2002.

Thanks All,

Now the only issue is whether it will mount on my first batch of 1000, Wetzler M6. An answer is not required; I will try it when I get back to the good 'ol USA in Feb. First stop: Micky Dee's.

-- Chris Chen (chrischen@msn.com), January 19, 2002.

Just to make sure someone doesn't get misled by what appears to be a not-quite-right metric conversion: The DR Summicron focuses, in close mode, to 19" which is 0.5 meter. Recent (1969 and on) Summicrons focus to 0.7 meter, which is about 27 1/2 inches.

-- Bob Fleischman (RFXMAIL@prodigy.net), January 19, 2002.