Miyauchi 20x100 Binoculars
by Bill Dellinges
In May of
this year I purchased a pair of 20x100mm Miyauchi binoculars from Texas
Nautical Repair Co. I found Epoch Instruments of San Leandro, Ca. to offer
the most generous discount as a dealer for T.N.R. I paid $3200 (list $3995)
plus another $200 for the optional interchangeable 37x eyepieces. This unit
has a five-element objective lens including a fluorite element (the
non-fluorite model sells for about $1000 less), Bak-4 prisms, and Kellner
eyepieces giving a generous eye relief of 27mm (I can just about see the
entire field with the eyecups folded down wearing my glasses. The field is
2.5° (1.8° at 37x). They are fully multi-coated. Weight is 13 pounds. I love these
binoculars! Stars seem to be quite sharp near center with a slight bit of
coma about halfway to the edge, not bad for f/5 binoculars. It's wonderful to
pan the star fields with them and see the "big picture" after years
of high power/narrow field views in telescopes. I have seen the roundness of
M57 and resolved doubles down to about 13.7" (Beta Scorpii) at 20x. I
also barely split Gamma Arietis at 7.6". At 37x I can see the hole in
M57, belts on Jupiter, clearly resolve Saturn's rings and two moons, resolve
M22 and split doubles down to 6.4" (45 Herculis). I recommend some type of
viewfinder, even with the unit's 2.5° field. I have a Celestron Starpointer
mounted on the binocular's handle, which works great. I can't imagine using
them without it. If you were to see M24 or M7 in these babies on a dark
night, I think you would be sold on them too. I'm very happy with my
Miyauchis and plan to be buried with them. Addendum
to Miyauchi 20x100 review (February, 2004): A little more than three years
since my original review, the price of this binocular appears to hover around
$3735, up from $3200. There is now a set of 26x eyepieces (ep’s) available
($335) in addition to the optional 37x eyepieces. The new 26x ep’s render the
same field of view (2.5 degrees) as the 20x ep’s. Their eye relief is
slightly less than the 20x and I can see only about 2/3 of the field with
glasses on and the rubber cups folded down. This is still a vast improvement
over the 37x ep’s that have the worst eye relief I’ve ever encountered. Their
rubber cups are too short to fold down; your eyes must be literally pressed
against the ep’s to see into them. It would be impossible to use these 37x ep’s
with eyeglasses. It should be noted the Miyauchi 20x, 26x, and 37x ep’s are
proprietary to this 20x100 binocular. That is, they have outside barrel
diameters slightly larger than the standard 1.25”, so that other ep’s you may
have cannot be used in this binocular.
The pictured Davis-Sanford tripod used to support the Miyauchis has
been replaced by a Bogen 3051 tripod and Bogen 3433 video head, a combination
I feel works well in supporting and using this large binocular (Miyauchi
offers an expensive fork mount/tripod that bolts to the binocular sides). Omitted in the original review
was the fact that this 20x100 fluorite model, unlike the semi-APO
non-fluorite 20x100, has extendable dew caps and interchangeable ep’s. I found the individual focusing ep’s too
easy to rotate. Even gentle contact of the eyes on them tended to defocus the
image. I fixed this problem by getting - from Texas Nautical Repair - a
heavier grease to apply to the inside focusing sleeves (minor disassembly of
the ep housing was required-if I could do it, anyone can). The inter-pupillary distance adjustment
mechanism has the opposite problem - it’s too stiff, but I’ve learned to live
with it. Nevertheless, I still stand
by my original positive review: their breathe-taking views more than make up
for the minor gripes noted above. |
||
|
|
||
|
|
