Image of the day

Captured by
Lawrence Parchman

Eastern Veil Nebula

About Astromart

My Account

New to Astromart?

Register an account...

Need Help?

Posts Made By: Jeff Verona

August 28, 2002 11:27 PM Forum: Equipment Talk

Refractor Opion Needed

Posted By Jeff Verona
How about the Stellarvue AT1010? 80mm, f6, $450. Several people have purchased one for use as a guidescope but ended up using it as their principal visual/photographic scope. If you decide to go with a 5" scope, you'll need a beefier mount, one that would be hard to "grab and go" with.

October 31, 2002 02:13 AM Forum: Eyepieces

Meade research-grade ortho's

Posted By Jeff Verona
I have a 7mm Meade RG ortho. Here's the description. The ep has a brushed aluminum barrel. IIRC, all the Meade RG eps have that barrel. On the top of the ep are the words "Meade" and "Or7mm" in white type, along with "MULTI-COATED" in blue type. My review of the ep, with pictures, can be found at http://www.cloudynights.com/eyepieces2/meadeor.htm.

It's a great eyepiece. In both my 480mm fl and 1200mm fl scopes it shows bright stars/planets against a jet-black background. FOV is only 42-43°, but it's dead sharp to the edge.

Hope this helps.


Jeff Verona

December 13, 2002 07:12 PM Forum: Equipment Talk

Siebert?

Posted By Jeff Verona
Don't know about the origins of "Erfle," but it's pronounced "ur-full", with the second "u" barely vocalized.

Jeff Verona
Whose M.A. in English occasionally comes in useful

December 28, 2002 09:56 PM Forum: Equipment Talk

Fully-illuminated field

Posted By Jeff Verona
Thanks for the help. What I'm specifically looking for, I guess, is how large a light cone you can get for a given aperture/focal length combination. For example, suppose I had a 6" f/10 Mak. How large will the image circle be at the visual back? If it's less than 35mm, then it wouldn't make any sense to use a 40mm eyepiece. Anybody have a quick equation for this, or does it depend so much on baffling, etc., that it has to be computed based on the actual design and build of the scope?

February 27, 2003 04:59 PM Forum: Equipment Talk

Does Tak Mewlon 180 have refractor performance?

Posted By Jeff Verona
Here's one review:

http://www.excelsis.com/1.0/entry.php?sectionid=12&entryid=436


I've seen comments elsewhere that the 180s were very hard to collimate and tended to lose collimation (which goes against what the review says).

No information on the Vixen, but at your price point you could afford a 7" Russian mak that would be as good or better. Check the APM and ITE websites.


Jeff Verona

May 11, 2003 03:57 PM Forum: Astro-Physics

AP 6" F/12 Superplanetary Refractor

Posted By Jeff Verona
I observed through one at NIAGfest. It was on a simple, non-motorized GEM. The views of Saturn were stunning, even at relatively low power (<200x). Seemed optically equal to a TAK FS-152.

Jeff

May 11, 2003 04:03 PM Forum: Telescope Making

Newbie Question

Posted By Jeff Verona
Well, there are a couple of possibilities:

1) Inspect the lens cell (if there is one) closely; most are marked with the aperture and the focal length. If the lens is unmounted, on rare occasions you can find that info printed on the side.

2) Take the lens outside during the day, and hold it up by the wall of your house. Point it at the Sun (DON'T LOOK THROUGH IT). Walk back and forth until the light passing through the lens focuses at a point on the wall. Measure the distance, and that should roughly give the focal length.

BTW, surplus optics need to be treated with caution. Only properly-matched doublets or triplets are suitable for astronomic use. There's lots of old military glass out there which was designed for photography, and it's not really suitable for telescopes.


Jeff

May 11, 2003 04:09 PM Forum: Equipment Talk

H-alpha filters

Posted By Jeff Verona
Check out the Coronado website: http://www.coronadofilters.com/


Sit down before you look at the prices :-0



Jeff

May 24, 2003 02:38 PM Forum: Equipment Talk

Airline carry-on scope/optics

Posted By Jeff Verona
Well, there are the Uti travelscopes...I believe they're an Astromart sponsor. If you look through the past couple years of SKY AND TELESCOPE, you will find many examples of DIY travelscopes.


Jeff

June 19, 2003 08:05 PM Forum: Astro-Physics

Astrophysics

Posted By Jeff Verona
Astro-Physics is the name a telescope company from the Chicago area. They make premium APO refractors with long waiting lists. Superb quality, and almost a religion to some.

Jeff

Funding Member

Sponsors


View all sponsors

Search