M1 Crab Nebula

[Hicks]

Whilst there's still many things to improve on this image, I'm quite pleased I got this much out of the nights session. I was setup earlier than normal and drift aligned quicker too. Went inside, focussed and took a few test exposures, all was going great. Then the connection to the scope/gear went down.

Few hours later after trying all sorts I figured at -5c the cold was causing issue with the Olimex A20 I use in a drybox so I switched it out for a raspberry PI + new hat pcb I've made for powering it (and focuser/serial and temp monitor, but those are not quite ready to use yet). Issue sorted I could finally start to image. Or so I thought.

Guiding in RA was fine, guiding in Dec, utter disaster. In the end I went with one direction dec guiding (spent a few hours today stripping the Dec mount down and fixing up the slop so now it responds to guide rate changes much better). In the end though it guided just about and the result was about 23 exposures that were good enough to stack.

Hopefully I'll be getting a zero image shift stepper focuser soon which should help no end and with the earlier changes to the dec axis and learning a little more about PID controllers to tweak the guider settings, I'm hopeful the next session will go a little better.

I expect I can get more out of this data with more processing practice but I'm overall quite pleased I got something at all out of the night and tbh it's likely my best image to date. Criticisms welcome.

If anyone is interested in the Pi Hat saga there's a few posts (more to come) on my blog that provides a little detail along with pictures.

Details:

• 8" LX90 @ ~f6.3
• SXVR-H9 and a Lodestar OAG.
• 11x180s and 13x120s + bias/darks/flats

[simmo39]

Nice start despite the mount problems.

[SkyBound]

If you are getting the Meade zero image shift focuser, it is NOT a stepper motor, but just a 12v DC motor, just thought I would mention that, so you will not get repeat position focusing with a DC motor.

but you picture is very good, I too have an LX90, I have a Feathertouch crayford on the back with there stepper motor, expensive but absolutely superb.

[Hicks]

@SkyBound: I looked at the Meade a while back and was put off it for that reason. I really want a stepper/absolute position based focuser especially once I add filters to the mix.

I'm getting close to buying a moonlite focuser. Chatted with Ron about it to find a setup that would work on an 8" LX90 with the focal reducer mounted inside the focuser. I'm just holding off until I've fully tested the controller I plan to use with it.

[toxic]

very nice indeed