Astromart

May 18, 2015 11:20 PM Forum: CCD Imaging and Processing/Deep Sky

3rd image for April M-88/M91

Another winner!

Rolando

May 28, 2015 11:19 PM Forum: Eyepieces

Widest AFOV in a 1.25" 35mm or 40mm EP

In a 1.25" ocular, you have at most an entrance aperture of 1.1 inches (28mm) to play with for the field lens size. That is the maximum field size that will fit inside your eyepiece and that determines the max viewing angle that you can get with any focal length eyepiece.

Therefore a 35mm focal length eyepiece will have a maximum apparent field of just under 44 degrees. For a 40mm eyepiece you could squeeze in only 38 degrees.

Rolando

May 30, 2015 08:04 PM Forum: Astro-Physics

Moon Mosaic with Copernicus and Straight Wall

Posted By Roland Christen

Straight Wall, stack of 21 video frames out of 100.

Rolando

June 1, 2015 07:27 PM Forum: Mounts

Paramount MX+ VS AP1100GTO

Posted By Roland Christen

Yes, we use a Delrin gear for the first reduction from the high speed motor. The advantage of Delrin is low noise, very low wear and precision. The first gear operates at very high speeds, which is difficult for metal gears to handle.

The tracking accuracy of the mount does not depend on the first reduction gears, rather it depends on the worm, which is precision cut and measured for accuracy in our own facility. Even without PE correction, the worm drive of the AP 1100 mount is typically under 5 arc seconds, and with PE activated it will be in the range of 1 arc second or less.

We spend a great deal of time and care producing this geartrain. It is most accurate, I assure you. There are also other advantages to our mounts besides accuracy. They do not need a computer to operate. They run off 12 volts, so can be used in the field with a simple 12 volt battery. The mounts set up rapidly in the field and can be polar aligned easily with optional right angle polar scope. Call George at AP and he can fill you in on all the features that are inherent.

Rolando

June 1, 2015 07:28 PM Forum: CCD Imaging and Processing/Solar System

Saturn 31 May 2015

Posted By Roland Christen

Very very nice! Excellent resolution.

Rolando

June 11, 2015 07:20 PM Forum: Astro-Physics

Imaging with the F4.6 Quad TCC

Posted By Roland Christen

This crop is at full resolution.

Rolando

June 11, 2015 08:45 PM Forum: CCD Imaging and Processing/Deep Sky

Astro imaging with the new Quad TCC

Posted By Roland Christen

This crop is at 100% resolution.

By the way, I have some good news for the 140 TEC owners. I believe this telecompressor will also work very well with that scope, and most probably reduce or eliminate the slight blue defocus of the older lenses. I will be testing this with one of the original 140 scopes in the coming week. The TCC fits onto the 3.5" Feathertouch focuser, the only thing you need is the quick connect adapter that screws right onto the drawtube.

Rolando

June 15, 2015 11:24 PM Forum: Landscape Photography