Image of the day

Captured by
Herb Bubert

Crescent Nebula

My Account

New to Astromart?

Register an account...

Need Help?

Posts Made By: Jim Nelson

April 25, 2003 09:03 AM Forum: Deep Sky Observing

Spring the Season of galaxies. Boring...

Posted By Jim Nelson

Spring is deadly for public star parties, if it weren't for catching some of the late winter stuff before it sets, and maybe some of the early summer stuff as it's rising.

I'm still "mastering" the Virgo cluster and environs, so I have that personal project. From a good dark site, I'm impressed and suprised at what I can see in galaxies with my 6 inch dob, but from my usual haunts I, too, am aching for a little variety.

Hey, Vladimir, there's some pretty nice spring planetary nebulae out there which should look pretty good in your 10" SCT.

May 6, 2003 08:42 AM Forum: Deep Sky Observing

It isn't fair....

Posted By Jim Nelson

"ny advantages? Ursa Major, Ursa Minor, Cepheus, Cassiopeia, Draco and much of Camelopardalis and Lynx are circumpolar. Who would really care for this?"

Well, Cassiopeia is pretty nice. Bajillion nice clusters. Small comfort,though. I think *I'm* too far north, at about 43 degrees north. At least I get all of Scorpius. (Barely.)

May 16, 2003 08:15 AM Forum: Eyepieces

UO Konig vs. Konig II

Posted By Jim Nelson

Well, after a little bit deeper searching I found some consensus that the older Konigs are 1-2 (3 element) eyepieces and the newer ones are 1-2-1 (4 element) eyepieces...

1. Anyone say otherwise?
2. What's the difference in performance?

I have an older 16mm Konig which I've used a few times, and I love it, but it's a bit weird. Very large AFOV, but very tight eyerelief. Sharp and bright as all get-out, though. Barlowed, it gave me the best view of M13 I think I've ever had, a couple of weeks ago. I have a 12mm that I haven't tried out yet.

Curious as to how the new models differ.

May 19, 2003 01:34 PM Forum: Equipment Talk

90 mm f/10 decent?

Posted By Jim Nelson

The 90mm will be great for those hazy or not-so-great nights when the 10 inch can't live up to its full potential anyway, and you may not feel like lugging the darn thing around and waiting for it to cool. I don't have experience with that specific model, but as Jim G. indicates it seems like a decent scope.

As a concrete example of "better image quality" that Jim G. mentions, my 6 inch reflector will walk all over my 70mm refractor pretty much any night...BUT, take for example Castor. In my 70mm, it's a lovely sight almost any night, barring the absolute worst conditions. Tight, but nice. My 6 inch will always split Castor, but in non-steady skies the little star images may be crawling all over the place, without any diffraction rings, etc. So while my bigger scope isn't performing any *worse*, technically, than the little guy, the little guy's image just plain looks nicer.

So I think the 90mm would be an excellent complement to your dob.

June 7, 2003 03:49 PM Forum: Equipment Talk

Which scope then?

Posted By Jim Nelson

I have the Orion 6 inch f/8 dob; on a good night I could quite easily see Io against the clouds of Jupiter, with its shadow trailing, with tons of fine detail on the planet itself.

But, on most nights I see diddly, at least by comparison. Michigan seeing is typically lousy. But on good nights it's capable of suprising views.

I can't do the comparison among these scopes you mention, but I can't find a darn thing wrong with my Orion dob (well, motions are a little tight for viewing above 200x, but Michigan seeing usually makes that point moot).

The Hardin scopes are the "new kids on the block", and seem suspiciously cheap, but I've only heard good things about them - but not careful, analytic reviews. I've seen a 10 inch Hardin, at it *looks* like a cheap scope, but the owner seem quite pleased with it.

Discovery scopes also have a good rep, but I've never actually seen anything to convince me that they're significantly better than the Orion dobs. They may well be, but I suspect people also just tend to prefer American vs. Chinese made 'scopes on principle.

June 17, 2003 09:03 PM Forum: Equipment Talk

Antares Super Plossls

Posted By Jim Nelson

The Antares Super Plossls, I believe, are the same design as Celestron Ultimas and Orion Ultrascopics, and in fact are from the same manufacturer. These are not really Plossls, but a 5-element design that performs similarly to a good Plossl. I think the consensus is that the Ultimas/Ultrascopics are in the same league as the Televue Plossls, and if they aren't as good they're really, really darn close.

My Ultrascopics (I have the 35mm and 15mm) are probably my most used eyepieces.

June 23, 2003 12:32 PM Forum: Equipment Talk

FINALLY!!!!!!!!!!!!!!!!!

Posted By Jim Nelson

I grabbed a view of M13 in a fellow astronomer's 10-inch dob this weekend and "wow, omg, " really only begins to describe the view, don't you think?

Sounds like great fun! I plan on *eventually* upgrading to a 10 inch dob in the hopefully-not-too-distant future (when I stop being a poor student and get a real job).

I recently purchased the very nice Stardust obseving chair, and as happy as I am with my "new toy", your post is giving me major scope envy.

Have fun for the both of us!

June 25, 2003 06:59 PM Forum: Equipment Talk

Orion Mak vs. Stellarvue refractor

Posted By Jim Nelson

I've looked through and played with a SV 102D on an alt-az mount, and it's a superb wide-field instrument, especially if you spring for some widefield 2 inch eyepieces; the view with a University Optics 40mm MK-70 was mesmerizing. If you have dark skies to observe from (Mauna Kea would count, I think smile ), I'd recommend it. For high power, plan on getting a good barlow (or springing the $$ for some long eye relief, ultra short focal length eyepieces).

At higher powers the chromatic aberration on the SV 102 becomes an issue (for me it did, I'm not used to it since I use a reflector, primarily), and the Orion Mak would probably be better on Mars, but with the Mak you'll be limited to nothing wider than a 1.1 degree field. This is OK, and the Mak is cheaper, but I think the SV would ultimately be more versatile.

June 25, 2003 09:35 PM Forum: Equipment Talk

UO 24mm Konig vs. 25. Super Erfle

Posted By Jim Nelson

In the "Eyepieces" forum, I posed a similar question not too long ago, although I was more interested in the 16mm range in that discussion.

The consensus seems to be that the Konigs give sharper images. However, they have quite short eye relief at the shorter focal lengths (esp. the 16mm, which I can say does give great views AND has wicked short eye relief). At the 24/25mm level, eye relief probably won't be an issue. At f10, both should have reasonably good edge of field.

June 26, 2003 10:43 AM Forum: Equipment Talk

comparison

Posted By Jim Nelson

That's neat! The major "flaw" (in my eyes, my experience) is that the central hole in the ring is much less obvious in small scopes (looks more disk-like), and I think M13 looks better in a 6 inch, but this is a neat approximation. Does the dumbell really look that good in your scope? Nice!