Image of the day

Captured by
Alexander DiNota

NGC6960 Veil Nebula

My Account

New to Astromart?

Register an account...

Need Help?

Posts Made By: James DellaPenna

September 20, 2003 07:32 PM Forum: Astro Binoculars

New to astrobinoculars--need advise w/ problem.

Posted By James DellaPenna

Although I am well equipped regarding telescopes the only binoculars I own are a pair of 35-year old Belmont 10 x 50's made in Japan. I tried them out for the first time on the sky last night and was extremely dissapointed with the results. When looking at a single source target such as Mars it revealed two images side by side. Twisting the binoculars closer together reduced this effect somewhat but no matter what I did I could not eliminate the double image. This problem has probably always existed during daytime use but was masked by the overall sceinc view as apposed to a tiny single point target.

Is this a problem with a cheap pair of binoculars, astigmatism in my eyes, or possibly both? I wear driving glasses for astigmatism but don't need them with my telescopes (with one eye closed) so I did not use them with the binoculars. In fact, until I began writing this thread, my glasses never even occurred to me.

I would like to purchase something in the 12-to-20x by 60-to-80mm range for new binoculars but don't want to spend several hundred dollars if I'm just going to experience the same problem.

What's happening here?

October 16, 2003 02:35 AM Forum: Equipment Talk

First Light w/ Nexstar 11 GPS

Posted By James DellaPenna

My first light attempt with the Nexstar 11 GPS ended in failure last week when I inadvertantly reversed polarity on the power cord pin, blew the fuse in the DC adapter cord, and was out of business elctronically. I pushed on in manual mode but soon discovered the Nexstar 11 makes a poor dob!

Tonight was my first official first light (with power). I passed up on the GPS Align option due to lots of trees on my northern & southern views opting instead for Auto Align. Since the scope came from an Astromarter in Ohio I expected I would have to enter my own lat/long coordinates the first time but it somehow already knew where it was. After the scope chose its 2 alignment stars and I got them centered I achieved successful alignment on first attempt!

I proceeded to go to several objects with reasonable accuracy (Polaris was a tough alignment star due to trees) but eventually had azimuth slewing problems due to cord wrap. Apparently I had not entered the cord wrap feature correctly. This was an opportunity to shut down, restart, and try Two Star Alignment where I choose the stars. Using Vega & Alpheratz I once again got successful alignment on first attempt. This time I spent a tad more effort getting dead on centering with alignment stars and the results were nothing less than perfect. Go To commands were entered for Mars, M13, M57, M15, M31, Double Cluster, Albireo, M92, and M27. In every instance the Nexstar slewed to center or near center of my 32mm wide angle EP.

After having struggled with the erratic results of an LXD55 GoTo mount the Nexstar 11 GPS is a dream to operate. I spent a lot of time reading the manual before rushing out with the scope and that really paid off. I was honestly expecting major rookie problems with the Nexstar but that proved not to be the case. This is a scope I would recommend to anyone looking for excellent quality in GoTo equipment.

October 27, 2003 01:49 AM Forum: Celestron

Did a Nexstar No-No, need advice.

Posted By James DellaPenna

Yes, I read the warning on page 12 of the manual that said to loosen the clutches on the Nexstar 11 GPS prior to transport but promptly forgot about it when I drove 77 miles to the Mid Atlantic Star Party with the azimuth clutch fully locked!

The result was a steady deterioration of the slewing capability to the point where it will hardly slew at all in azimuth. A local dealer who was present doubted I did any real damage but suspected there is probably a loose set screw somewhere that needs to be accessed. He suggested I would probably have to have the Celestron tech department talk me through it.

One can never reach anyone live at Celestron and a call-back has about a 1% chance of reaching me while I am home with the scope.

Has anyone else dealt with this problem? If so, how did you get it resolved? Are there published instructions with photos available anywhere regarding service of the clutches?

Would appreciate any advice from sage Nexstar veterans except for suggestions to visit the Yahoo discussion group. I do not care for the Yahoo site and wish to handle it on Astromart. All other help is welcome. Thank you.

November 17, 2003 08:26 PM Forum: Deep Sky Observing

DSO magnitudes-vs-Star magnitudes

Posted By James DellaPenna

I'm sure this subject has been discussed before but I have never followed this particular forum previously.

Is there a general rule of thumb regarding "observable" DSO magnitudes-vs-Star magnitudes? In other words, might a 10th mag galaxy generally equate to a 12th mag star, etc? I realize the degree of light spread is a key factor along w/ seeing conditions; I'm just wondering if there is a generaly accepted average magnitude spread of observability between stars and DSO's.

Applied Example: If I have an SCT capable of magnitude 14.5 am I generally wasting my time looking for 12th to 13th magnitude DSO's?

December 30, 2003 10:13 PM Forum: Equipment Talk

Gotta ask a dumb question!

Posted By James DellaPenna

Just acquired an old C-8 SCT with the red secondary cover. Since there does not appear to be any collimation srews or even access to any, how does one collimate these old OTA's?

January 1, 2004 03:23 AM Forum: Off Topic Discussions

My New Years Projection

Posted By James DellaPenna

Both of the next two Mars landers will be blazing successes. How's that for going out on a limb?

January 1, 2004 09:42 PM Forum: Equipment Talk

Polaris Mount-vs-Super Polaris

Posted By James DellaPenna

What is the difference between a Polaris and a Super Polaris? Is it just the electric drive?

January 2, 2004 02:04 AM Forum: Equipment Talk

Celestron SPC-8 years of manufacture?

Posted By James DellaPenna

I have a Celestron black tube SPC-8 SCT OTA I would like to sell but would like to be able to advertise year of manufacture or at least a range of years. I know this model w/ 6x30 finder was introduced in 1984. Celestron offered an upgraded version the same year called the C8+ but does anyone know if they still kept making the SPC-8 past 1984?

February 1, 2004 03:05 AM Forum: Equipment Talk

Crosshair reticle source?

Posted By James DellaPenna

Aside from the AM member who apparently got deleted for being a non-sponsoring business, is there another source for crosshair reticles built like filters that can be screwed into the bottom of eyepieces?

This seems like a very practical way to modify any 1.25" EP for star alignment rather than buying one particular crosshair EP for that purpose.

February 8, 2004 03:32 PM Forum: Equipment Talk

Super Polaris Mount question

Posted By James DellaPenna

The photo below shows the manual R.A. control of my Super Polaris mount of mid 1980's vintage.

Newer non-electric models show the metal box that would house an optional R.A. drive motor which I understand is identical to the CG-5 motor assembly. Also, the metal motor housing box normally slides up a plate which is part of the axis housing. The motor bracket is normally anchored into that plate with mounting screws.

My Super Polaris model has no motor housing box and the axis housing has no mounting plate for a motor. If I wanted to acquire a R.A. drive for this mount what do I ask for and how would it attach?