Radar 460 Report post Posted November 6, 2017 Check this screenshot out. I'd polar aligned and was getting great alignment. I turn on the air conditioner inside my observatory to get the camera down to minus 20 and the PA plot goes crazy. This tells me that I either need to ensure the inside of the observatory is always at the same temperature (pretty hard to do in Australia during summer) or that I need to cool down the pier to a specific temp whenever I perform PA. In the plot below, where the graph begins to go up, that is the moment I turned on my air conditioner. I had no idea my pier was so temperamental. Ideas on how to solve this welcome. Ray Share this post Link to post Share on other sites
Radar 460 Report post Posted November 6, 2017 Turning the air conditioner off has the opposite effect, almost instantaneously. Very surprised how easily the pier loses PA with temperature. Ray 1 Share this post Link to post Share on other sites
wingeing Pom 584 Report post Posted November 6, 2017 Make the pier out of Invar Greg 1 Share this post Link to post Share on other sites
poppasmurf 301 Report post Posted November 6, 2017 Might explain your recent problems mate. Between movement when extended and changes with temp. I would ditch that pier for a more standard design. Shane 1 Share this post Link to post Share on other sites
Radar 460 Report post Posted November 8, 2017 Might have to design with a material that hardly expands. Not sure what the Invar cost will be, but I'll do some digging. Ray Share this post Link to post Share on other sites
wingeing Pom 584 Report post Posted November 8, 2017 I was joking Ray - Invar costs a fortune Greg 1 Share this post Link to post Share on other sites
beren 26 Report post Posted December 24, 2017 Ray coming in late but here's a local option .....Pegasus piers https://www.facebook.com/pegasuspiers/ {in Queensland} talked to the owner {Phil} on options for myself and he seems like a great option at a decent cost Share this post Link to post Share on other sites
Radar 460 Report post Posted December 24, 2017 Very interesting mate. They look well built as well. I'll check them out in the coming days. Ray Share this post Link to post Share on other sites
Radar 460 Report post Posted December 30, 2017 Problem with guiding on the south celestial pole seems fixed. My guide camera wasn't square to the RA and Dec. I rotated it so it was perfect and I am getting round stars again. Must have knocked it sometime without realizing. Anyway, getting some good data, back to collecting photons. Ray Share this post Link to post Share on other sites
Radar 460 Report post Posted January 2 I have wrapped the aluminium lifting column with insulation. I will do a test tomorrow, polar align, turn on air con, see if things shift. Fingers crossed. Otherwise it is water cooling for the camera. Ray Share this post Link to post Share on other sites
Radar 460 Report post Posted January 2 (edited) Insulation working incredibly well. Goodbye sudden temperature drops ruining my imaging runs. We love physics. Ray Edited January 2 by Radar 1 Share this post Link to post Share on other sites
poppasmurf 301 Report post Posted January 2 Nice job on working out a problem and coming up with a cheap solution Ray. Damn moon and/or clouds here so I haven't been collecting any photons at all. I guess that means more for you . Shane Share this post Link to post Share on other sites
Radar 460 Report post Posted January 3 6 hours ago, poppasmurf said: Damn moon and/or clouds here No cloud for the first time is ages, but I'm only shooting narrowband during the full moon. That will be my thing now, I'll do the RGB during new moons. The weather has changed so much over the last few years, so much cloud that I have to grab whatever nights I can. I'm enjoying being out there again. Ray Share this post Link to post Share on other sites
poppasmurf 301 Report post Posted January 3 Unfortunately I don't yet have NB filters, although the plan has always to get some eventually. I tend to laugh at anti climate change comments, as an amateur astronomer, the proof is in the change to observing/imaging time available compared to several years ago. When I first got into planetary imaging it was during the decade long drought, and 99% of the time was cloud free and great seeing and transparency, having said that it was great when the drought broke. Shane Share this post Link to post Share on other sites
Radar 460 Report post Posted January 4 22 hours ago, poppasmurf said: 99% of the time was cloud free and great seeing and transparency Same here in W.A. Such a difference now compared to a decade ago. Plus, most climate change deniers are not scientists, they are armchair experts with no scientific skillset that have probably watched some diatribe on Facebook or somewhere, so I find it entertaining they lock horns with people that have written a thesis on climatology. N.B certainly maximises the time you can image. The full moon is no longer a hassle with N.B. Ray 1 Share this post Link to post Share on other sites
