AP130 Version 1.8: Adding a Focus Motor to the Guidescope
Dates: December 10, 2020 - May 10,2021
A second Pegasus Astro Focus Cube 2 was added to the TV76 guide scope
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Why a focuser for the Guidescope?
Basically, I am making this change to make the platform consistent with the WO132 platform. I would like to be able to focus the guide scope remotely under computer control. I would also like to have the ability to swap cameras and use the TV76 as a wide field imager (using the AP130 as the guide scope.
I did run into one issue. The Fous Cube 2 is a heavy little piece of gear and I now had two of them hanging off one side of the telescope tube. This made things very hard to balance. To address this I also added a 3rd axis counterweight to the front of the dovetail base on the opposite side of the scope. This really helped a lot.
Updated Narrowband Filters
In some previous narrowband images, I was starting to see cases where I was getting halos around brighter stars when using the ZWO OIII filter and to a lesser extent when using the ZWO SII filter. These filters are cheaper than many and because of this, there are some trade-offs. I have not had any problems with the LRGB filters, but 7nm cut narrowband filters are super tough to make. These are stacks of dielectric coatings - I am now sure how many - buy when I had similar filters designed when I worked at Kodak we needed over 50 coatings to get a sharp cut. They are a challenge to make well. I decide to swap to a set of Astronomiks 6nm Narrowband filters - these have anti-reflection coatings on both sides and have an excellent reputation for good performance. This did solve my problem.
Current Configuration
So here was where the AP130 Platform is at now:
Scope: Astro-Physics 130mm F/8.35 Starfire APO built
in 2003
Guide Scope: Televue TV76 F/6.3 480mm APO Dublet
Main Fous: Pegasus Astro Focus Cube 2
Guide Fous: Pegasus Astro Focus Cube 2 - new
Mount: IOptron CEM60 - new
Tripod: IOptron Tri-Pier with column extension - new
Main Camera: ZWO ASI1600MM-Pro
Filter Wheel: ZWO EFW 8x31
Filters: ZWO Gen II LRGB, Astronomks 6nm NB Filters -new
Rotator: Pegasus Astro Falcon Camera Rotator
Guide Camera: ZWO ASI290MM-Mini
Power Dist: Pegasus Astro Pocket Powerbox
USB Dist: Startech 7 slot USB 3.0 Hub
The ADM Off-axis counterweight conveniently clamps on the bottom of the dovetail base.
