Started warm and humid – but a cool front passed just around sunset. Clouds were a problem early on – after about 9:30 local time mostly clear, very occasional high clouds, low temps in the upper 50s, humidity around 50%, very little or no wind. Seeing is not great – maybe 2.2 arcsec.
Rig #1: WR134,135, & 137, also WR1
I got the declination assembly back this afternoon and installed on the AP1200. The motor is now much quieter, and so far I’ve noticed none of the intermittent power interruptions. Not sure how that could be related, just an observation at this point. The new motor runs much more smoothly. I setup on WR134 and began the sequence. Some clouds were passing through throughout the first cycle – the second time through was better with only very occasional or no clouds. Note that I only just barely had time to finish two cycles before getting into the maple tree. Noel Richardson preferred that I still try to get two cycles if I can – once that is impossible go to longer exposures for a single pass through. I got somewhat of a late start, but really only going to have another week or so where I can do two full cycles. Once finished (at around 12:30 following Beta Aqr image) I decided to try WR1 in Cassiopeia. At V=10.11 it’s likely too faint, but I’ll try a set of three 1-hour exposures to see what I get.
Rig #2: ASAS-SN 13ck
The clouds kept me from starting a sequence on V1101 Aqr – so I skipped it once it cleared and went straight to ASAS-SN 13ck. It is definitely fainter tonight, going with 1-minute integrations.
Some more ratty data!
Last night’s results were interesting to say the least. The data for ASAS-AN 13ck were a total mess:
I have no idea what caused the discontinuities in the light curves. My usual suspicion of scattered light just wouldn’t do that. It almost appears that the curve changes each time I stopped the sequence to focus. But plotting the image fwhm against the magnitude difference (shown in the blue curve) did not show a correlation. The thing is, the V1101 Aql data came out looking great, where the previous evening’s plot showed a 0.04 mag jump at the time of meridian flip.
Note there is no “jump” in the comparison star curve – in fact the standard deviation for the entire run is 0.007 mag. The thing that I noticed was that, for the September 4/5 data, looking at sample images before and after the meridian flip, the objects fell close to the same location on the before and after meridian flip image sets. But that is after having flipped the post-meridian images so that all images were East-Left and North-Up. In the case of the V1101 data from the previous night the objects were shifted by quite a long way, particularly in X. But, in the case of the ASASAN data, the images from Sept 3/4 were shifted by a lot, while from Sept 4/5 they were pretty close. Yet it is the September 4/5 data that is screwy. So exactly the opposite of what I’m seeing for the V1101 data. So what is up????
One thing for sure is that I am not going to figure it out tonight! Fading fast – nodding off. Out at 4:20am