8th-9th of June, A new T-Point Model and Data Acquisition Begins.

On Wednesday night I headed out to Kumeu Observatory around midnight, clouds and rain stopped me from heading out earlier, after arriving I had to then wait for another hour for the sky to clear up enough to bother opening up the dome, after gaining focus I imaged a microlensing target "OGLE_2017_BLG_0896" this time I tried to keep the dew strap turned off in the hopes I could gain better image quality but after just 20 minutes the corrector plate had fogged up, so I turned the dew strap back on and waited for the corrector to clear, unfortunately by the time the corrector had cleared the clouds came rolling back in and I only barely managed to close the dome before another rain shower hit, I waited for a while after this but with no end in sight for the clouds and rain I decided to pack down and head home around 3 am.

^ Dew on the inside of the corrector plate, it's looking like we will have to just work with the dew strap on or else risk not getting much done on clear nights.

Thursday was a lovely clear day so seeing my opportunity I headed out to Kumeu in the afternoon before sundown to grab sky flat's for calibration, while I was waiting for twilight I was visited by Steve Calveley and his wife, Steve owns the land that Kumeu Observatory is located on and he is also a past president of the Auckland Astronomical Society, I showed him all the new equipment in the dome and talked about our research projects, he was very happy to see Kumeu Observatory back in operation and shared some interesting stories about the observatory and the society from back when he was involved, he also expressed an interest in helping out with the current projects.

After Steve and his wife left I got on with capturing Sky flats, now that I have the flats for the "wratten filter" we can now reduce our image data correctly for submission, being there so early and with all our current targets very low in the sky I decided to have a go at doing a new pointing model using the T-Point add on for the Sky X, after a few failed attempts I figured out how to do it properly again and managed to get a decent pointing model, although I did have a few failed pointing samples near the almost full Moon, we could definitely see that there is an east / west bias that is indicative of mirror flop but at least we won't have to do star synchronization and solve images each night to be able to point the telescope accurately, hopefully it will stay reasonably accurate until we decide to change things again, while I was finishing my T-Point model Steve Hennerley showed up, so after looking at the results and having a chat we decided to get on with some image acquisition of the microlensing target "OGLE-2017-BLG-0019", we managed to grab 2 hours worth of data on this target as well as some new images of "OGLE_2017_BLG_0896", one of the best moments of the night came when me and Steve managed to identify the target star using the OGLE finder Chart.

<- The Ogle finder Chart image

And our image of the target, which is a crop from one of the original Fit's files ->

After Steve left to catch some sleep before work, I stayed behind and kept on imaging but I noticed that the auto-guider started losing it's guide star, I managed to resolve the problem eventually by disconnecting the camera and then restarting MaxIm DL, I then re-enabled the auto-guider in the telescope setup section and this seemed to fix the problem, although when your taking 5 minute exposures and run into problems like this you can end up wasting a lot of time and when your tired from being up late a couple of nights you tend to make mistakes, so after finishing off the two hours worth of images of the "OGLE-2017-BLG-0019" target and creating copies of the images that I then calibrated, I ended up closing up the dome and copied all the images onto my USB stick and headed home around 5:30 am.

I'm really looking forward to the next clear night and hopefully we will soon be able to complete our next goal which is to start submitting our data for analysis.

Posted by Jonathan Green