Gina

I'm finding I often want to go out and turn the camera for better framing. Currently using 0° and 90°. Makes me wonder if I can arrange remote control to rotate the camera(s). Both want to be at the same angle so one stepper motor such as a NEMA17 could do the rotating. Two problems come to mind - connecting the stepper motor to the cameras and ensuring that the cameras point in the same direction and don't move relatively as the mount rotates.

With the current (smaller) quadrant gear on the working rig I needed to move the focus about 10mm so with the longer arm is should be around 20mm. The rack is 60mm long so should give plenty of range.

Decided to go for a larger quadrant gear for focussing. The current remote focussing covers a lot bigger focus range than needed. I only need to accommodate the variations due to the lenses not being fully apochromatic - I can set the position approximately in daytime by focussing on distant trees then tighten the clamp on the focus sleeve.

Yes, my night vision has deteriorated too!!

Correct.

Sorry for the flippant remark but you started it by building a TARDIS 😀 Wonderful idea and build though.

You need a force field around the door to keep the rain out. If you have sufficient power, of course... 😁

I don't know what I'd do without a 3D printer these days. Virtually all my astro projects rely on 3D printed parts.

Drat - now I've caught that earworm off you 🤣

Oh dear I always hear the TARDIS appearing and disappearing sound when I read this!!! 🤣

After a rest, I decided to service my 3D printer and now trying a print of a bracket for the second camera. If that works and also the second bracket, I plan to swap to a smaller nozzle and try printing better focus gears. I've done this in the past.

I was about to ask the same questions. I have considerable experience of all sky cameras, mostly high performance ones. I always want the best possible astro images as you no doubt already know. OTOH watching out for incoming clouds is an important aspect.

Been sorting out the firmware for the RPi and I think I'm about ready again for imaging. Although I have been able to overcome the problem, there is a lot of backlash in the 3D printed gears that drive the focus sleeve from the 28BYJ-48 stepper motor. I'm going to try timing pulley and belt instead of spur gears and see if the sideways pressure on the focus sleeve due to the tension in the timing belt, affects the image at all.

I have the new micro SD card in the imaging rig RPi and what I have connected is working. The focusing seems reasonable with the resolution set to 2 which makes me think I was wrong when I thought I was using 16x microstepping. The 28BYJ-48 already has a 64:1 gearbox which, allowing for the approx 3x stride angle of a NEMA17, still makes around 20x the resolution of a NEMA17. Then there is the reduction ratio of 10:1 of the focus gears. Countering this is that the focussing range of the lens is from a few feet to infinity and we need very precise focussing. The full focussing range was previously of the order of several tens of thousands of counts and it needed the focus count to be within around 10 counts to get good focus. The focus position for Ha used to be around 8000. Now the range is 12,000 counts with the focus position for Ha at about 4000 counts so a resolution of 5 counts should work for the auto-focus routing. I was using 20 counts before which was the default as I recall - I think this was a bit course and the reason manual focussing gave better results sometimes.

ADM knobs certainly feel very cold!

Very interesting.

It doesn't work that way. In fact LRGB filters and mono camera is better than an OSC. An OSC will not only give you half the resolution for NB but have much lower sensitivity.

Those worked, giving status of progress and reducing write time to 15m - a third of previously. The different make of card could have made a difference though. Previously Kingston and this time SanDisk. The SanDisk 16BG cards seem to have a few more MB of capacity, so Kingston to SanDisk was fine. Kingston to Kingston was fine too with exactly the same capacity.

If you can afford it, going for 32mm filters may future proof yourself in case you go for a larger sensor than 4/3in. When I bought my Astrodon filters I was using relatively small sensors and went for 1.25" mounted. Now I have the ASI1600MM-Cool with a 4/3" sensor which gives slight vignetting bit this is completely corrected with flats.

Superb pieces of kit.

I want one 🤣

Very nice indeed.

Hmm... seems to be more to it than that. Set to 5 but the Options tab still only allows 2. I'll look into it tomorrow. If I have a problem sorting it out I'll just preset the microstepping to 16x. That will work whichever imaging system I use - just might be a bit slow on some.

No problem - changed from 2 to 5 in file rpi_focus.cpp in astroberry-diy directory. Maximum resolution switch 1 - 1/1 2 - 1/2 3 - 1/4 4 - 1/8 5 - 1/16 6 - 1/32 Note that values 3 - 6 do not always work. Set to 2 by default */ #define MAX_RESOLUTION 5

The clone works. One point though... The resolution is limited to full steps or half steps. For my lenses I want 16x microstepping so will have to patch the code.