Thursday, February 4, 2016

Automation Elation & Slewing Problem Again

I went out to Kumeu last night determined to figure out the T - Point automated calibration run, I was setting up when I was pleasantly surprised to see Allister had turned up to set up his giant binocular Dobsonian for some observational fun, there was a few clouds about but there were also plenty of big gaps so after getting the C14 focused, I started an automated calibration run, this time I just paused the run after each image was taken of the first six sample points that were all in the start region, I then right clicked the images and astrometrically solved them via the image link feature of the Sky X, this seemed to do the trick, as every sample point after these six would automatically solve and add the sample points, needless to say I was elated to have finally got the automated process working, I then proceeded to capture 61 sample points covering one half of the sky, Grant Christie had advised me to do half the sky at a time to avoid mirror flop issues, so once this was done I then proceeded to capture sample points on the eastern side of the sky, unfortunately the first row of points was below the level of the dome so I just skipped these points, I had captured about 17 points on the eastern side when clouds put a stop to any further efforts, so I took a break and went outside to hang out with Allister who by this point was packing up his equipment, by the time Allister left the sky had cleared up again so I continued the automated calibration run but after just a few sample points the slewing of the telescope started making the same unhealthy noise that I had reported after doing my manual pointing model, knowing that the solution to this problem was clearing the pointing model and being happy that I could now easily do a new automated pointing model, I deleted the pointing model that I had spent all night capturing, I then re-homed the telescope and turned off the Paramount thinking that this would solve the problem but when I restarted the mount and gave it a test slew it was still making the same unhealthy noise, so again I re-homed the telescope turned off the mount and this time turned the Sky X off, I then took a good half an hour break before restarting the Sky X and the Paramount but again the mount was making the same unhealthy slewing noise, I'm starting to think the problem may not have had anything to do with the pointing model after all because this was happening with no pointing model at all, not wanting to cause any damage to the Paramount I just re-homed the mount and turned it off, the next clear night I will head out and try the automated calibration run again but if the mount is still making the unhealthy slewing noise I will have to just wait until someone can come out and take a look at it as I have no idea why it would still be making this unhealthy noise when there is no pointing model, heading home I was elated that I had finally figured out how to do the T -Point automated calibration run but this feeling was tempered by the concern I have for the unhealthy slewing noise the mount was making, hopefully it's nothing too serious.

^ T - Point sample plot screen shot.

^ Allister's giant binocular Dobsonian ( built by David Moorhouse )

Posted by Jonathan Green

Wednesday, February 3, 2016

Automation Frustration

We had a clear night out at Kumeu last night, so I went out there with the plan of doing the automated T- point calibration, after taking a few images manually with the Sky X and astrometrically solving the images via the image link feature, I started an automated calibration run, I quickly became frustrated though as none of the automated images would solve, I found this to be inexplicable as I could pause the calibration run, right click on an image that was captured via the automated calibration run and open it up in the image link feature and successfully solve the same image that failed to solve during the calibration run, it wasn't like it was taking a long time to solve the image either, so after trying this more than a few times, I then decided I would just slew to each mapping point of the calibration run, take an image and manually solve each image, this would work up to at most 11 sample points but then after that I couldn't solve anymore images, it was like the image link would just start to fail to recognise the stars anymore even though to my eye the images looked the same from start to finish, I remember Grant Christie telling me that you could run into problems if the temperature compensating focuser (TCF) wasn't correctly tracking the temperature, I was controlling the TCF using Maxim DL as the Sky X still can't connect to the TCF since we had the power cut that I reported a few weeks back, so this might be the issue, although I'm really unsure about it, I did have the temperature tracking turned on in Maxim DL and I was watching the TCF and I could see it was making adjustments over the night so I really am quite perplexed, after attempting different exposure lengths and different binning modes without any luck, I really felt at a loss to why the images captured during the automated calibration run wouldn't astrometrically solve, maybe I need to adjust the detection threshold in the image link or something? I kept at it until 4 am in the morning becoming even more frustrated as the hours went by, clouds rolled in around 4 am putting an end to my efforts so I closed down the dome and called it a night heading home in frustration, I think I'm going to need some help with this as I re-read the T-Point manual today and could find nothing that would help me resolve the problem, hopefully once we get the TCF working with the Sky X again this will help although I'm still at a loss to explain why none of the automated calibration images would astrometrically solve.

Posted by Jonathan Green

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