Prod=
uct
Review by Bill Dellinges (January 2010)
Astr=
o-Tech 1.25”
Dielectric Diagonal ($69.95)
Purc=
hased
from Astronomics (astronomics.com)
A 1.25” dielectric diagonal for 70 bucks? I’ll take two. I
was slightly dubious about this company and their low cost scopes and
accessories. But I took a chance and ordered two to replace the enhanced
aluminum diagonals on my C8 and Televue Ranger. They had been in the ~93%
reflectivity range and these new high tech dielectrics claim 99% reflectivi=
ty.
I’ll have to take their word on that. I was delightfully surprised at the
outward appearance of the diagonals. I’d give the build quality an A. Overa=
ll,
it’s a beautiful looking diagonal. I especially liked the compression ring =
that
presses against the eyepiece to hold it place to prevent the set screw ding=
ing
the eyepiece barrel (albeit pretty standard these days). And the set screw =
is
beefy, making it easy to grasp and turn – not one of those tiny thin ones s=
een
on some cheap diagonals. The barrel that slips into the focuser has a deten=
t to
insure a positive lock down preventing the diagonal from falling out of the
focuser. The difference in light gathering between enhanced aluminum and a
dielectric will be subtle. I’m not sure I see a big difference in performan=
ce
in most applications. I did one experiment with the Ranger (70mm refractor)
where I compared the faintest stars I could detect in an open cluster with =
both
the old and new diagonals. The new dielectric did indeed pull in slightly
dimmer stars. So I do highly recommend the Astro-Tech dielectric diagonal.<=
o:p>
------=_NextPart_01CA992B.5E37F750
Content-Location: file:///C:/08A9448C/ProductReviewbyBillDellingesAstrotech1.25diagonal_files/themedata.thmx
Content-Transfer-Encoding: base64
Content-Type: application/vnd.ms-officetheme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------=_NextPart_01CA992B.5E37F750
Content-Location: file:///C:/08A9448C/ProductReviewbyBillDellingesAstrotech1.25diagonal_files/colorschememapping.xml
Content-Transfer-Encoding: quoted-printable
Content-Type: text/xml