Re: [Leica] Prescription lens for eyepieces

["Julian Koplen" <jkoplen@mindspring.com>]

Thank you, Richard.  I am originally from Danville and just moved to Myrtle
Beach a few months ago, so I am temporarily without "connections".

Is it relevant that Leica puts a -0.5 diopter in the M eyepiece and a -1.0
diopter in the R?  Or is that just another way of saying that the virtual
distance is 1-2 meters?  What is so confusing is that some people talk about
the virtual or projected distance and others talk in terms of the diopter
that Leica has already put into the M and R eyepieces.

If I cannot find a cooperative optometrist locally, would it make sense to
consider my own distance +4 correction as a baseline and then, using the
above Leica eyepiece information,  add an additional +0.5 for the M and an
additional + 1.0 for the R, giving me an add-on eyepiece of 4.5 for the M
and 5.0 for the R? That way, when I factor in the factory eyepieces, I'm
back at +4 for each?

Whew!

Thanks.........Julian

I will be glad to go off-list from this, but I do think it may be of value
to some other users.  The factory does less than an efficient job in
clarifying this for its customer base.  It would be nice if they simply
said, use your distance prescription, or use a 1-meter prescription.....or
whatever.

- ----- Original Message -----
From: Clompus, Dr. Richard [INN] <RCLOMPUS@INNUS.JNJ.com>
To: <leica-users@mejac.palo-alto.ca.us>
Sent: Thursday, January 13, 2000 5:53 PM
Subject: RE: [Leica] Prescription lens for eyepieces


Julian,

You only need to be concerned about your distance prescription (+4.00).  The
add power of +2.50 refers to your bifocal.  Most manufacturers place the
optical image from the focusing screen at 1-2 meters in front of the lens.
You will need a +4.00 or maybe a +4.50 diopter eyepiece correcting lens.
The best way to tell is to see an optometrist in the U.S. (or refracting
optician) in Europe and ask them to look through a spectacle trial lens of
these powers.  You will then be able to decide which of these two lenses are
best for you.  I don't know if Leica makes corrective eye pieces with a
prescription of +4.00.  Please check with your Leica dealer to see if they
are available.

If you have any further questions that I can help you with, please feel free
to email again.

Best regards,

Richard Clompus, OD
Roanoke, VA

- -----Original Message-----
From: Julian Koplen [mailto:jkoplen@mindspring.com]
Sent: Thursday, January 13, 2000 4:16 PM
To: leica-users@mejac.palo-alto.ca.us
Subject: [Leica] Prescription lens for eyepieces

I would appreciate information about how to obtain
prescription eyepieces
for M6 and R4.  My correction exceeds what is available "off
the shelf".  My
distance diopter correction is +4 and near is "add 2.5".  I
understand that
all I have to do is inform the optical lab that Leica puts
- -0.5 in the M
eyepiece and -1.0 in the R.

Does that make sense, and does anyone know of labs that can
fashion the
proper shape and size lenses that are required.

A related question, if anyone has direct experience, is
whether it is worth
getting the rotating eyepiece for astigmatism correction, or
is that feature
more trouble than it is worth?

Thanks for any help............Julian

P.S. Forgive if multiple messages appear.  I may have had
message format
problems.