Re: Jupiter 50mm/1.5 user report

[pgs@thillana.lcs.mit.edu (Patrick Sobalvarro)]

   From: Marc James Small <msmall@roanoke.infi.net>
   Date: Mon, 30 Dec 1996 18:45:41 -0500

   I've had four Jupiter-3's and two 1.5/50 Sonnars and still have two
   Jupiters and one Sonnar.  None have displayed coma.  In fact, the
   later of my two Jupiters (an '87 model from a yet-unidentified
   factory) comes bloody close to out-performing my 50mm Summilux.

I should hasten to add that the off-axis highlights that show the
tangential smearing typical of coma are out of focus!  These were
Christmas tree lights in the background when I was focusing on people
in the foreground.  Marc, could you check some of your photographs
made with a Jupiter-3 and see if there is tangential distortion in
out-of-focus off-axis highlights when wide open?

These smearings certainly do look like coma -- they get more
pronounced the further off-axis they are.  But I figure I should check
the case of highlights that are in focus.  Tonight, as a test, I shot
some Christmas tree lights in a darkened room that were in focus -- if
these have the same tangential distortion, then I agree, the lens is a
dog.

The numbers are: N742104, chromed aluminum barrel, looks quite new,
says YuPITER-3 with Cyrillic letters (I'm using the usual translations
of these into the Roman alphabet), 1.5/50, and there's a weird little
design that could be a schematic representation of an eyeball with a
ray emanating from it, or could be something else I don't recognize.

- -Patrick