Posts Made By: Dan D DuBal

Standard HDPE (in fact, polyethylene in general) has two major shortcomings as a structural material:
1) it is practically un-glue-able
2) it is not resistant to UV-induced degradation

"UV-stabilized" polyethylene *is* available at slightly higher costs.

Best wishes.
-Dan

Short answer: yes, if the head assemblies utilize beamsplitters (i.e. *not* two-channel designs for stereo microscopes) and if the assemblies can be "reduced" down to their basic components (beamsplitter, left/right prisms &/or mirrors, and housings). Some heads -- particularly older units -- may include auxilliary/supplementary optics such as incline prisms, relay optics, or perhaps polarizers. Most modern/current microscope designs are more modular; polarizers are located elsewhere, and incline prism and relay assemblies are removable.

My own Leica binocular viewer came from a recent Leica DL series research microscope. It was designed for 30mm eyepieces, and its clear aperture is 22mm. Its optically superb. Currently, it's outfitted with standard 1.25-inch eyepiece collars (my own tinkering) and a standard 1.25-inch eyepiece/diagonal barrel (threaded to a self-made baseplate). Nikon, Zeiss, and Olympus make similar binocular assemblies for their research microscopes. Some of the assemblies are designed for widefield &/or ultra-widefield microscope eyepieces. As such, their clear apertures are usually 22-23mm. Heads designed for 23mm microscope eyepieces will likely have ~18mm clear apertures.

Of course, the big step is successfully adapting it for use with a telescope. Many folks do so.

The best binocular heads from any/all of these big four makers are optically superb -- as good or better than the best binocular heads marketed for astronomical telescopes.

Hope that helps a little.
Best wishes and luck.
-Dan

--Not all of them.

More and more are designed for 30mm eyepieces and are *very* similar to, say, the BW/Lumicon binocular viewer (which is, itself, converted from a microscope head).

Cheers & best wishes.
-Dan

Perhaps there's some flexure/tilt of the Bino Vue, relative to the scope's optical axis?

The usual tilt/miscollimation checks apply to binocular viewers as they do to other accessories. See if the fresnel pattern changes orientation when (or after) you:
-rotate eyepiece(s)
-rotate viewer
-nudge/rock viewer (verify aligned/seated in focuser)

Also, can you detect any tilt in the focal plane, while using the viewer? Do stars on one side of the field reach focus just a hair "before" stars on the other side, or does the entire field (as best you can discern) reach focus at the same "point?"

One more question: is the Bino Vue being used "solo" -- without an auxilliary corrector/relay/Barlow?

Them be my wonderings, at this stage.

As for detecting misalignment of the binocular itself (i.e. split images/fields not aligned/identical), that's simply a matter of locking the system down while focused on a stationary target -- preferably a distant one (a mile or more away, if can) which allows good/thorough visual orientation of the image -- and comparing one eyepiece's view with the other. Rooftops, walls, fences, a line of trees -- these are some examples. Blinking back/forth while comparing the images (left, right, top, bottom) will show you (quickly) what's what. Most folks' eyes can accomodate minor left/right (divergence). Top/bottom misalignment (dipvergence) poses more trouble for the eyes; even minor/subtle dipvergence can prevent binocular merging &/or cause significant eye strain. If you know the range & size of the target being observed, you can use geometry to get a fair estimate of the degree(s) of divergence &/or dipvergence present. Typical standards for field binocs are about 15 arcmin. dipvergence, ~30 arcmin. divergence. My own personal standard is *zero* dipvergence (or darn near it) & <15 arcmin. divergence.

Indeed, it's never a bad idea to check with David or Al or anyone else at Tele Vue.

Best wishes and luck.
-Dan

The Widefield line was discontinued almost 10 years ago. The Panoptic design enjoys a slight advantage (+3 degrees) in apparent field, as well as significant advantages in both eye relief and extreme off-axis fidelity with faster scopes. As Victor noted, the Widefield's apparent field spans 65 degrees. The design produces eye relief right at ~60% of inherent focal length. (The Panoptic: ~70%.) The 40mm Widefield's eye relief is ~24mm. The design includes 5 elements in 4 groups. Here's a general description of the design's layout/sequence:
field lens: double convex singlet
interior field lens: double convex singlet (diff. radii)
interior eyelens: plano-convex singlet
eyelens group: double-convex/double-concave achromat

Excellent eyepiece. You have a keeper.
Best wishes.

I may be biased, but I'd pick "none of the above."

Gimme a Pentax 75 EDHF or SDHF. A well-kept EDHF will outperform any of the scopes you've noted, and it can be had (rare as it may be) for less than $750 (perhaps as low as $650). Well-kept SDHFs will bring a bit more -- say, $850 to $950.

Heck, from what little I've heard/read to date, the Orion 80mm ED may likely outperform them, too.

Best wishes and luck.
-Dan

If the Cubs lose, they have themselves to blame -- not some half-baked lame-o "curse," and certainly not some spectator who may (or may not) have prevented a single put-out (no guarantee Alou would have caught the ball -- just ask Alex Gonzalez). Besides -- Gonzalez's error cost the Cubbies FAR more than the not-caught foul ball.

The Cubs had already begun to crumble. Prior was out of gas, and Baker left him in. Farnsworth didn't help. The Marlins just kept hitting.

Those Cubs fans who believe their beloved Cubbies "lost the World Series" last night are a bunch of goofballs. If they're THAT ready to give up, then to heck with 'em. Furthermore, those Cubs fans who blame the spectator for last night's loss aren't mere goofballs; they're disrespectful crybabies. The Marlins might have had a *little* something to do with their victory, last night.

And let's not forget -- this was Chicago's *second* "match point" chance. If they'd won Game 5, we wouldn't be yackin' about all the foul ball (or Prior's collapse, or Alex's error, or the 8-run onslaught, or Game 7, or...).

Hurling cups, cursing the guy, and threatening his life -- *those* are the buttheads who should be marked.

As Harry would have said, "Hooooly Cow!"

The Tele Vue 2/1.25 adapter is one of the "tallest" available. A "shorter" adapter (one without that shoulder) should do the trick.

A 1.25-inch diagonal would also bring your smaller eyepieces within the focus range.

Best wishes and luck.
-Dan

Thanks for sharing, Tyler. It's been a while since I've been to Utah. Last time I traveled through the basin was April '98. I'd like to return and spend more time in the basin. Did you take these shots from the State Park? I can't tell if those are the Sheeprocks in the background or not.

Awesome stuff. Thanks again.
-Dan

Posters can pay more attention.

Posters can also delete mis-posted messages and re-post them in the appropriate forum.

That's my take, anyhow.

Best wishes.
-Dan