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Posts Made By: Dan D DuBal

November 23, 2002 09:13 PM Forum: Eyepieces

7mm and made by whom?

Posted By Dan D DuBal

Not exactly sure who actually made the Easy-View line, but Apogee Inc. sells the most recent generation (called Super Easy-View). That's apogeeinc dot com.

Easy-Views (and their newer versions) have a solid reputation, and many folks swear by them. They sport long eye relief (considering their focal lengths) and excellent fidelity, and accomplish both at a *very* reasonable price.

Todd Gross reviewed a couple of them on his website. Go to the Astromart home page, and follow the "Educational & How To" link (bottom). There, you'll find a link to Todd's domain.

Best wishes.
-Dan

November 26, 2002 08:02 PM Forum: Deep Sky Observing

What the heck is this?

Posted By Dan D DuBal

It is indeed a very red star (sorry, I don't know its name or designation) -- visible in all M43 pics I've run across. Note its position as the apex of an equilateral triangle, with NU (aka HD37061, at the "core" of M43) and the dimmer star at the tip of the "comma" both serving as the other two corners.

You should see this puppy in infra-red. Check this SEDS image:
www.seds.org/messier/Pics/More/m43_2ms.jpg
and compare it to any other non-IR pic. It's amazing how many "invisible" red stars clutter this field.

I'm going to have to pay particular attention, next time I'm cruising the M43 region. I know it's dimmer than mag. 9 -- maybe magnitude ~12-ish(?).

If anyone else has more info, please chime in.

By the way -- very nice shot, Andrew. Lots of structural detail and plenty of color info, too. Thanks for sharing.

Best wishes.
-Dan

December 3, 2002 07:47 AM Forum: Refractors

Restoring a Cooke

Posted By Dan D DuBal

Thanks for sharing, Kevin. I'm sure this wonderful classic is a great kick in the pants for all who are lucky enough to use it (or be around it, for that matter).

Beer vat dome?!? Now THAT sounds like the perfect shed project! :-)

Cheers and best wishes.
-Dan

December 3, 2002 08:56 PM Forum: Off Topic Discussions

Backing out of deals

Posted By Dan D DuBal

Yes, I have the following opinion:
You're mistaken.

Downhill fast? Hardly.

I'm sorry you've had bad luck. All I can say is "hang in there." That's hardly great advice, but it's all I have. I've never had a bad deal (or even a semi-fishy one), so I can't quite relate.

EBay is a different animal (auctions vs. classifieds). Many people prefer it. Many others prefer Astromart. I enjoy both. Of course, I've not yet *sold* any goods through either of them. When I do, I'll do it here.

Best wishes and luck.
-Dan

December 7, 2002 01:48 PM Forum: Equipment Talk

New Celestron Mounts

Posted By Dan D DuBal

Well SURE they'd sell a ton of them. But a go-to 9.25 for under $2000? Seems a bit much to ask, in my opinion.

The Nexstar8 GPS runs $2000. Meade's 8-inch LX90 (UHTC) runs $1700.

No one-armed Nexstar or LX55-ish/CG5-ish mount's going to handle the 9.25.

Celestron's GPE series is aimed *squarely* at Losmandy G11/Gemini buyers. They'll sell plenty.

Best wishes.
-Dan

December 11, 2002 07:02 AM Forum: Equipment Talk

Older Eypiece Design

Posted By Dan D DuBal

Quality is quality, and blah is blah. (Flair for the obvious, eh?)

Fact is, many of the low-cost brand-new (or "no-brand" new) standard eyepieces (i.e. Kellners & Plossls) are just not very well executed -- regardless of their inherent potential. I'll take a fine Kellner over a ho-hum symmetrical Plossl or Abbe every time.

The only time I *don't* like the 1.25-inch cone-top design is when eye relief is ~15mm or more. In my case, that viewing position places my eye too far rearward -- result being, I can actually see *around* the body of the eyepiece itself (the cone-top doesn't quite fill my eye's field of view, and there's a little "leakage" at the perimeter). Of course, this is easily remedied with an eye cup (I use "donuts" of pipe insulation foam, which serves double duty as a superb dew-preventer). When shorter eye relief is encountered, yes, the cone-top design better "fits" the recessed structure of the human eye socket.

On the other hand, my eye socket absolutely *loves* the fit and "feel" of my 18mm Meade Superwide's cupped/dished top.

Best wishes.
-Dan

December 14, 2002 10:28 PM Forum: Deep Sky Observing

Things that aren't there......

Posted By Dan D DuBal

The Rosette (NGC 2237) is indeed huge -- roughly twice the diameter of the moon. Because it's so large, it can be a bit stubborn when larger scopes are pointed right at it.

The cluster NGC 2244, on the other hand, is relatively bright and has a distinctive, easy-to-identify shape. Some liken it to a ladder; others see a resemblance to the constellation Gemini. Once you've located 2244, you've found the "heart" of the Rosette. The brighter clumps and swatches of the Rosette are, for the most part, "outside" 2244's brighter stars; so pay attention to the area beyond the main cluster. Scan around it -- perhaps even try *without* filters.

From dark sites, under skies with good clarity, the Rosette is an easy binocular object. Many folks can see it with their unaided eyes (averted vision) -- again, that's from *dark* sites.

A search on "ngc 2237" and/or "ngc 2244" will yield many links to many images of the nebula and cluster. Some of these may help in "getting a feel" (becoming familiar) for the field.

It's there. Really. :-)

Best wishes and happy hunting.
-Dan

January 3, 2003 09:11 AM Forum: Zeiss

Another Eyepiece Question

Posted By Dan D DuBal

You have a pair of Zeiss microscope eyepieces -- likely built with 23mm (.917-inch) barrels, subsequently modified (by owner, not by Zeiss) with 1.25-inch barrels for astronomical use.

The "pl" references "planokular." These are flat-field eyepieces (as most, if not all, Zeiss microscope eyepieces are).

The "10x" designation refers to their magnification factor when used with a standard (250mm focal length) microscope. Hence, yours are 25mm eyepieces.

The "18" designation refers to the eyepiece "field number," or field of view (field stop, actually). Yours have 18mm field stops.

I'm not sure of the lens design -- I'm guessing they utilize four elements in two groups, but I may be wrong. They are "orthoscopic," though not the classic Zeiss-Abbe design. The 18mm field stop yields around a ~42-degree apparent field.

Have you tried them, yet? Let us know what you think. I suspect they're superb (even if the fov isn't expansive). I have a newer T-coated Pl 10x/18 3-element aspheric, and it is absolutely fantastic. The eye relief's a bit extreme (long), but a foam eyecup solves that annoyance very nicely.

Perhaps another reader can offer a little better insight as to the lens design.

Best wishes.
-Dan

January 8, 2003 09:25 AM Forum: Astro Binoculars

Still Getting into my new 15 x70s

Posted By Dan D DuBal

Good to hear, Daryl.

I should receive my own 15x70s today (Galileo version). Probably check 'em out tonight and give a little blurb tomorrow. A thorough evaluation will eventually follow. I don't expect them to "wow" me nearly as well as my 10x70 Fujis, but for 80 bucks, I figured what the heck.

Cheers and continued amazement.
-Dan

January 9, 2003 08:04 AM Forum: Equipment Talk

Williams Optics 2" Diagonal and UO MK-70

Posted By Dan D DuBal

While I'm not declaring the following to be SAFE, I (that's *ME* -- not necessarily you or anyone else) would probably try a *brief* dose of heat to the diagonal's eyepiece collar. It might expand enough (relative to the eyepiece barrel) to loosen its grip. I'm thinking maybe about three seconds with a standard cigarette lighter or wooden match under a portion of the collar (don't try and heat the entire circumference; maybe a thumb-sized area about .5-.75 inches below the top/rim of the collar). After three seconds, remove the flame and quickly try to dislodge the eyepiece.

I would try *neither* a hotter flame *nor* a longer-duration heating, as there's tricky stuff involved (i.e. glass, conductivity, differential expansion).

Again, that's what I myself would probably try. I suggest gathering more folks' advice before trying *anything.*

Best wishes and luck.
-Dan