SpaceCat Automation Build, Part 1

Starting in on the SpaceCat automation build. The goal of this build is to automate as much of the capture process as possible, including focus, field rotation, and capturing flat calibration frames. The field rotator and flap panel are useful for framing, but can be especially useful when capturing mosaics. I will also be adding a filter drawer to avoid having to disassemble the optical train just to change out filters, and upgrading to a better field tilter.

This sort of build is a first for me. As such, I'm using it to try out and experiment with automation. Doing so in a relatively small format with the SpaceCat 51 helps to minimize the cost. It also helps that Deep Sky Dad offers these automation solutions specifically for the William Optics CAT Series telescopes.

Having already removed the stock tilter to repair the built-in rotator, I went ahead with installing the FR1 Field Rotator. 

The built-in field rotator of the SpaceCat has M56x0.75 female threads, while the FR1 Field Rotator has M48x0.75 female threads on both sides. I ordered a Blue Fireball M48x0.75(m) to M56x0.75(m) adapter to install between the built-in camera rotator and the FR1 Field Rotator.

To my surprise, the FR1 Field Rotator came with an M48(m) gender changer. Which I wasn't expecting. The conversion ring was relatively simple in design, though. There was no flange around the middle to prevent it from threading all the way through the body of attachments, or to keep it centered between the rotator and the OTA. It also wasn't slotted to allow easy removal with a lens spanner in the event that it became thread locked, but that likely wouldn't be an issue in this case.

Expecting to have to provide my own adapter, I ordered a Baader M48 Conversion Ring / Gender Changer (#2958555) to install on the camera side of the FR1 Field Rotator.

With the FR1 Field Rotator laid camera-side down on the desk, I removed the OTA from its single mounting ring and threaded it onto the telescope side of the FR1 Field Rotator. 

Note that removing the OTA from the mounting ring makes it easier to handle, and easier to thread the connection. Which also makes it less likely to cross thread any of the parts.

With the FR1 Field Rotator installed, the OTA is then reinstalled on the mounting ring.

At this point, I went ahead with installing the FP1 Flap Panel as well. However, I ended up removing it because the AF3 Autofocuser needed to be installed first. 

While installing the FP1 Flap Panel though, I noticed that the flap didn't align perfectly with the dew shield clamp ring. I tried re-aligning it by adjusting a few of the screws, but it seems the misalignment is more of a design flaw than an assembly issue. When connected to the motor, the flap panel is offset slightly to one side. I'm concerned that any attempt to correct it may put excess strain on the drive motor. In hindsight, I probably should have left it alone.

I'm not entirely sure how all this equipment is going to be laid out just yet. If I attempt vertical symmetry, the flap panel motor and housing would end up blocking the light path of the guide scope. When using the side mounting solution for the autofocuser, the field rotator and flap panel could either be oriented vertically, or to the side opposite of the autofocuser. The guide scope could then either be mounted off to the side if there's room, or piggy-back off the main OTA as it normally would.

Continues in Part 2 of the SpaceCat automation build.