Which binoculars do I have?

Started by ks1u, 12/15/2009 09:18PM
Posted 12/15/2009 09:18PM | Edited 12/15/2009 09:36PM Opening Post
I recently bought a used set of APM Binoculars. Over the years, the specifications have changed somewhat and the manual only says I have something in the 800000 series. The eyepieces which came with it are 20mm and 10mm SWA yielding 20x and 40x. So, I must have a 400 mm focal length. But the person I bought them from said the eyepieces yielded 25x and 50x. The tubes don't seem long enough for this to be so, but I don't know how much the prisms or any additional optical elements add to the fl. Does anyone know when these were made, how many elements in the objective and what type of glass in the objective. They accept and bring to focus my 24mm Panoptics and 13mm Naglers. Thanks for any information. BTW they perform very well.

George

Attached Image:

ks1u's attachment for post 49442
Posted 12/15/2009 11:52PM | Edited 12/16/2009 12:18AM #1
It would appear to be similar to ones from this ad placed by
APM on astromart in 2005. See ad for details:
http://www.astromart.com/classifieds/details.asp?classified_id=364062

Interestingly, the ad claims that standard 1.25" eyepieces will
not focus, yet you say views in Naglers and Pans are good.
I note that this later ad talks about ED glass, higher
powers 25x and 50x, and the statement about standard 1.25"
eyepieces not reaching focus is gone:
http://www.astromart.com/classifieds/details.asp?classified_id=590126
Perhaps that is what you have? The only difference I can
see in the two ad photos, is that the later ED version has
a bell-shaped housing on the front objectives. I can't
really see this area very well in your photo.

Attached Image:

m87's attachment for post 134569
Posted 12/31/2009 06:09PM #2
Definately the later version. I have a set of the earlier ones that wont come to focus with standard EP's. Mine is 20x and 40x and the newer version comes with 25x and 50x


20" MidnighTelescopes f/5
8" f/16 Muffoletto Achro
Meade 6" AR6 f/8.0 Achro
Celestron C11
Parallax PI250 10" F/5 Newt
Vixen FL102S,NA140SS,R200SS
80mm Stellarvue Nighthawk with WO APOupgrade lens, 90mm f/16.67 Parallax Achro
LXD75/LX200, Mini-tower, GP-DX, CG5 ASGT, LXD650, GM-8, G11, GM-100, GM-150EX, GM-200 and a Gemini G40
4" portable AP convertable 44" or 70" pier
Stellarvue M7 Alt-Az, TSL7 Pier/Tripod
12.5" f/5 MidnighTelescopes DOB Swayze optics
Monroe GA