From: Milton Aupperle <milton@outcastsoft.com>

Date: November 4, 2011 1:12:31 PM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] LX90 Fork Mount or CGEM Handcontroller?

Hi Kirk;

On 4-Nov-11, at 12:30 PM, KirkusMcGurkus wrote:

Hi Milton,

I'm still planning my new mount/scope purchase and keep coming up with questions.

Can I use Astro IIDC with Meade Alt/Az mounts such as the LX90 ACF?

For guiding no. Not unless it's using an optional Equatorial wedge ($200+) so that it's running in a Equatorial mode. Doing AZM control is a major PITA (Pain In The A**).

Also, I know that I can use it with a Celestron CGEM via A Shoestring GPUSB, but do you know if I can bypass the GPUSB and go directly to the Celestron hand-controller? I did this previously on an LXD75 (didn't need the GPUSB).

No you can't. The Celestron / Skywatcher etc. mounts that use the NexStar Protocol only support "GoTo" moves and do not support arbitrary slewing.

The LX based mounts (like your LXD 75) support arbitrary time based slewing, which works just fine.

The issue is that to move a Celestron / Skywatcher mount, you first read the current location, then compute your offset in RA and Dec coordinates and then tell it to "GoTo" the new coordinates. It simply does not have the precisions to move the mount to sub arc second locations and it's also very slow to respond too (read coordinates - wait - write coordinates - wait - repeat and rinse).

The direct connect via the ST4 port and the GPUSB or the GPIO to ST4 board (for PGR Cameras) solves the latency issues and gives direct control of the motors.

I'm just trying to get my ducks in a row before purchasing anything and, like I've said in the past, I'm so happy with, and experienced at using your software, I want to build my new equipment around it if at all possible.

Cool.

Thanks for the years of wonderful support!!

Glad it's working for you. Now if we could only convince the "I use a Mac for Astronomy people - but the truth is they run Windows software in emulation mode all the time and may as well just buy a PC instead of a Mac" crowd, then I'd have much better sales numbers.

PS to the Group:

Is anyone interested in a  Tutorial / guide of how to import the Simple Table Photometric Light Curve data that Astro IIDC generates into "Plot"? I have a template "plot" file all set up to handle JDN data on the horizontal axis and the magnitude stuff on the vertical axis. I directly import the files into this Plot template, delete a few data columns and my graphs are pretty much ready to go in a few minutes without needing to put the data in a spreadsheet or other data manipulators.

My work flow to process 6 hours of asteroid data taken at 25 second intervals (2.4 gigabytes or 894 frames) to apply darks, flats, field de-rotation and then Photometric data reduction is about a 10 minute process on my i7 Mac Book Pro. It takes about 30 seconds to import and arrange the data in Plot and then maybe 5 minutes to  generate the data and smoothed curves before data labeling. So I have my Photometric graphs done in 30 minutes from start to finnish.

Milton Aupperle