First of all I have to thank Frank for saving my imaging session this morning with Metaguide. Titan was close by last night (before midnight actually so technically some of this data is from the 17th). It had an obvious flare. Apparently, I wasn't the only one with collimation issues last night from reading other posts. This is unusual for this scope as it's pretty stable and holds collimation well plus it's permanently mounted in it's building. Saturn was in the south eastern sky only about 40 degrees above the horizon which is an unusual location for me to image towards. Maybe that was it. In any case I made a quick adjustment and clear up the flare and continued on with my Saturn imaging. Frank hasn't saved the day (night) yet but stay with me.
After imaging Saturn I left the scope and computers out (covered against dew) but ready to go. In fact I cut my Saturn session short by an hour from the planned imaging session because I just couldn't say awake anymore. Got about 4 hours sleep ahead of the GRS transit this morning. Woke without the alarm clock about 30 minutes earlier than planned and got outside. Good thing I did because when I pointed to Jupiter the image was horrendous. Three Galilean moons were tightly clustered away from Jupiter a bit so I slewed to those to see if I could determine the trouble. Once again flaring on all the moons and worse than for Titan earlier. (As you will see in this thread the Saturn data came out very nice and the collimation was good for that data collection) Anyway, reached down to tweak the collimation and the screw came loose in my hand!!!. Image jumped off screen (which can (WILL) happen when one of the three collimation screws becomes disengaged from the mirror support!!).
OMG not what. Opened up the ROI to full chip and found Jupiter again. Centered the moons again (after 6 or 7 tries trying to remember how to reduce the ROI without FC centering on Jupiter instead of on the moons where I wanted it to point!! UGH just more sleep deprived screw ups on my part). Anyway we got things close again after a few minutes and then worked the screws to make sure they were all well seated. (Having an image on the screen is a real help hear as you move screws, just make sure the image ends up back where it started from and you can adjust fairly quickly to get close.)
I was so far out though I couldn't depend of moon flares to dial in the scope. Launched Metaguide and sure enough red dot was pinned on the right hand side. Couple of tweaks and got it centered up. Good to go. The entire episode only cost me about 20 minutes but it's nice to know (I mean REALLY know, that your collimation is dialed in when you see that red dot centered and a nice first diffraction rings surrounding it) The Jupiter data looks good too but there is a lot of it and it will be awhile before I get that organized into something presentable.
Without further ado, here is a 5-image derotation towards the end of my Saturn data. I'll get an animation together shortly but here is a good start. I can't believe we saved to session (Frank and I) and I really can't believe this is the third night in a row with interesting Saturn events to display. I rushed this one so it's a little ratty. I'll do a more thorough job of it as the day progresses.
Note: I used the Background enhancement tool to bring Titan into better visibility during the sharpening portion of the processing.
Edited by dcaponeii, 18 September 2024 - 04:59 PM.
