[MF3D.FORUM:988] Re: New Ekeren MF viewers

[Greg Erker <erker@xxxxxxxxxxxxxx>]

>The lenses are the Horizon medium format 4X loupes that
>have been discussed on this list.  As it turns out, the
>Horizon loupes, IMO, are a definite weak point of the viewer.
>The initial impression of excellent crispness, sadly, only
>holds for a small sweet spot in the center of the lens, and
>only while viewing the center of the image.  The corners
>are definitely fuzzy, enough so to be disturbing to at
>least some users.  I found it very bothersome; some people
>only noticed after it was pointed out to them; and one
>person I handed the viewer to put it down within a few
>seconds saying "there's something wrong with the lenses."

 I bought a pair of the Horizon 4x MF loupes
from Steve Berezin to build a quicky "mailable"
viewer for sharing my slides with people.

  I ended up selling the loupes to my brother
for roughly the above reasons.

  The loupes are quite a bit higher magnification
than the 35mm 4x Horizon loupe that I also have.
I estimated the FL of the 6x6 loupe at high-60's
to low-70's millimetres.

  They also appear to have lots of field curvature
since I couldn't find a focus setting that gets
the corners and center sharp at the same time.
My brother (with younger eyes) has less problem
with this. As does Steve, who's optometrist told
him he has unusually good accomodation (not an
exact quote).

  The diameter is decent but not 40-some mm like
my current viewer. So combined with the high mag
makes it hard to see the whole slide without
moving your eyes back and forth.

  In the end I sold them to my brother for a slight
loss. So we are both happy.

Gotta go - Greg