Gina

The new RPi has arrived, I've set up WiFi and have it working with the camera and lens so now have the ASC working in its "naked" state. Adjusted the focus as I had knocked it. It's a very delicate operation to do by hand and I'm wondering whether to reinstate remote focussing. Something to look into. Installed the bare camera and lens unit back on the observatory corner post. Here's an image. Think the focus is a bit off but I'll see when the stars appear.

Done some more wiring up and sorting out the final arrangement but still waiting for the replacement RPi 3B+ due today.

Interesting 😀 I've never tried NB for galaxies other than Ha to show the star generating regions otherwise LRGB filters. Nice result.

Just seen this!! PHEW bet that was a gut-wrenching experience!! Glad it isn't as bad as it first looked. Lucky you had a spare front ring. Good luck with the repairs.

Useful for a number of things. Thank you for posting.

Thank you very much Carole.

Power wired to HAT plus Peltier TEC and dew heater wired up. Connected the water pipes to the waterblock and screwed the mounting part onto the box.

Thank you very much. Very probably. This is something I'm planning to look at.

Ha and OIII combined HOO > RGB. Processed in PixInsight and GIMP. 2h Ha plus 2h OIII integration time captured concurrently on my dual imaging rig. ASI1600MM-Cool cameras set to unity gain, Astrodon 3nm NB filters and Asahi (Pentax) SuperMultiCoated Takumar 200mm f4 lenses.

Taking two lots of subs at the same time helps. One camera taking Ha and the other OIII.

This project has just taken a step backwards - the RPi 3B+ has died!! Another on order due Sunday. I thought I had a spare but can't find it. Doesn't stop my continuing with doing the other bits though.

Thank you everyone - much appreciated. Yes, I'm pleased with it.

IC1396 bi-colour image HOO > RGB. North at top. Ha and OIII Astrodon 3nm filters, Asahi SMC Takumar 200mm f4 lenses and ASI1600MM-Cool cameras. 5m x 51 = 4h 15m total integration of Ha subs and 20m x 9 = 3h total integration of OIII subs. Cameras at unity gain (139). Processed in PixInsight and GIMP.

With no imaging for a day or two I'm expecting to get on with this project and put the camera and lens in its box with dome to keep the weather off the lens. So far I've been using just the ASI178MC and fish-eye lens, with the camera mounted on the SE corner post of the observatory and I can only do this with the roof open. I'm looking forward to having it in its permanent position with full weather protection. This will be on an aluminium tube as mast with the ASC just above the observatory roof.

Remote focussing now installed and working. This is focussing on a comms mast over 5 miles away. These pics show zooming in right down to pixel level.

Thank you very much, Sara.

Now printing the parts for remote focussing.

Rather you than me - don't think I'd have the patience! That is one hell of a project

Current dual imaging rig with 200mm lenses.

I'm leaving the mounting as it is for now since I'm not losing much due to misalignment.

This is the result of an imaging session last night and early this morning which shows the amount of misalignment. With the image area loss being quite small it seems unnecessary to produce a new mounting system.

I have managed to pull M5 screws out but only with getting them very tight many times. I agree that for this application, threaded holes should be fine. These adjustments will not need to be very tight. I expect the amount of adjustment to be no more than 0.3-0.6mm from experience with the current rig so a mm or 2 should be fine. I see no reason to do it with both lenses.

Something like this might be good but I think I can do it with 3D printed parts and metal nuts (eg. T nuts).

The arrangement on a finder-scope is two screws and a spring on the third leg. I was considering doing the same but springs and plastic don't go well together as a continuous force can cause plastic to deform so maybe three screws and loosen one while tightening another.

I see your points. I was also thinking in terms of a scope rings type arrangement. I do use threaded holes in the printed parts but make sure the stress is kept within limits. For instance, the part holding the pair of cameras and lenses is attached to the dovetail with 6 M6 screws with 10mm long threads. Each imager weighs over a Kg with the lens much heavier than the camera and I wouldn't want that much weight on a few screw threads in plastic. Embedded metal nuts are a possibility. The amount of force needed to hold the back of the camera is quite small with all the weight on the lens mounting which was why I thought adjusting the camera would be easier.