Got a very late start on this target because apparently either my USB-3 hub or cable failed such that the computer couldn’t see any of the peripherals, so I went back to my old USB-2 hub and repeater cable and all was well. The Wizard was already descending into the Provo, Utah light dome by the time I got started, but I wanted to give this one a shot because the Moon is getting bright and the imaging scale is about right for further testing of my off-axis guider / focal reducer combination. As with the last night I tried, I had some trouble finding a sufficiently-bright guide star. I went to 4-second exposures in an attempt to improve my chances and did find one without moving the prism. My worry is that I’m often going to have issues when doing automated meridian flips. Anyway, in this case I found one, got 2 1/2 hours’ worth of integration, then apparently lost the guide star for a couple of hours. (I haven’t actually looked at the Sequence Generator Pro log to figure out what happened, but I might have had some tree branches in the way). Interestingly, eventually the system reacquired the target (automatically, no intervention from me) and I got several more good subs before dawn ended the session. So I didn’t get as much integration on the target as I was aiming for, but it still turned out better than my last previous attempt; I guess the off-axis guider and a couple of years’ additional experience do help. I would really like to put the focal reducer on the guide camera to improve its speed and field of view, but can’t figure out how to get enough back focus to do that short of drastic measures like remounting my primary mirror (which I’m not willing to do).

Date: 11 Nov 2016

Subject: NGC 7380, Wizard Nebula

Scope: AT8IN+Antares 0.5x focal reducer

Filter: Baader Planetarium 7 nm Hα

Mount: EQ-6 (EQMOD)+PEC

Guiding: Orion TOAG +DSI Ic+PHD 2.6.2.4 (Win 10 ASCOM)

Camera: DSI IIc, no chiller CCD ~5 °C

Acquisition: Sequence Generator Pro 2.5.2.4 with Nebulosity 4.1.1 ASCOM camera driver (Win 10)

Exposure: 19x600 s

Stacking: Neb 4.1.1, bad pixel map, bias included, 33 flats, match histograms, trans+rot align, Nebulosity 1.5σ standard deviation stack. Resize 2x (Catmull-Rom spline).

Processing: StarTools 1.4.316: Crop; Develop: 75.86%; HDRptimize; Deconvolute: 2.9 pix; Track: Smoothness 75%, 4.5 pix. Photoshop CS6 + Astronomy Tools: Levels; Astroframe.