[Leica] 400 f/6.8

["Gib Robinson" <robinson@sfsu.edu>]

Hokay,

Feedback from this group and from Leitz (I sent a fax as recommended here
and got a phone call from Rockleigh!) suggests that the 400 f/6.8 is a
better choice than the 2X plus 180 f/4 Elmar. Looking at the information I
have about 400 f/6.8 I can see I have MANY options to sort through. Looks as
if there were at least four different stocks made and several iterations of
the lens with and without filter holder, with and without extension tube
capacity, with and without third cam. Whew! If I want to simplify my
choices, this definitely isn't the way to do it! So, for starters, I'd love
some feedback about which of the options REALLY matter.

1) Lightmetering. I have a pair of R-4S bodies so it makes sense (I think)
to look for a 3-cam version, but what exactly is the difference? As far as I
can tell, the third cam activates the meter but does not provide information
about the diaphragm settings, so you have to stop down to get an accurate
reading. I assume two cam and older you can't use the meter at all. Oct 31,
'76 is the date of the shift to the third cam but I have no idea what the
serial #'s were for that era. Is there a place I can check?

2) There is an extension tube that allows for close up focusing (under 8
feet). I think the early models were not designed for that. I don't know
when that change-over occurred. I assume it was prior to October 31. 1976.

3) Shoulder stock. There were four distinct models (five counting the
proto-type). I don't know whether there were significant differences. The
latest appeared in 1985, I believe.

So far I have run across one lens for sale with a serial number of 2435492,
but I have no idea when it was made. Is there a resource that will help me
date the lens by the serial #?

Thanks very much for the help.

Some day soon I plan to complete this R-Leica update venture and start
talking about the real "focus" of this group. I did own a "long" lens for my
M-2 -- a 135 Elmarit f/2.8 with goggles but it was heavier by itself than my
M-2 and four other lenses. Kinda defeated the purpose.

- --Gib