My main effort when I took this image was trying to test my newly-completed Robert Brown stepper motor-based focuser for my camera lens and to get more data for my Orion Hubble palette image, but after Orion set I had a little time before Monoceros disappeared behind the neighbors’ trees and decided to try that. So this image doesn’t have as much data as I’d really like (it doesn’t have any true R data or L data as I used the Hα for both R and L, and it is woefully short on B). There’s terrible optical error, I believe because the belt I used to connect my focuser motor pulley to the lens pulled the lens out of alignment so its optical axis was no longer perpendicular to the imaging plane of the camera. You could watch the in-focus stars march across the image from bottom left to upper right as the focus was adjusted. I’ve since redone the belt setup. Better data will have to wait until next season. I tried to crop out the worst of the optical error. But I was pleasantly surprised by the overall result so I’m going to go ahead and post it. I'm amazed at how much nebulosity shows up in this area when you use the Hα filter. Oops, this is in Monoceros, not Auriga (guess I was thinking of the Tadpoles and Flaming Star, and that's what I get for using plate solving to do all my finding). Corrected!

Date: 17-18 Mar 2017

Subject: Christmas Tree Cluster/Cone Nebula Region of Monoceros

Scope: Tamron 135 mm f/2.8 lens stopped to f/4

Filters: ZWO 31 mm diameter unmounted G, B, 7 nm Hα

Mount: EQ-6 (EQMOD)+PEC

Guiding: 9x50 Finder/Guider + DSI IIc+PHD 2.6.2.10 (Win 10 ASCOM)

Camera: ASI1600MM-Cool, -20 °C, Gain 300 Offset 50

Acquisition: Sequence Generator Pro 2.6.0.17

Exposure: 28x180 Hα, 45x60 G, 12x60 B

Stacking: Neb 4.1.4, flats & darks, trans+rot+scale align, Nebulosity 1.5σ stack and align.

Processing: StarTools 1.4.327. Aggressively stretched the Hα. Combined HαGB in Neb 4 and stretched and attempted to color balance and correct in StarTools; used “cap green to yellow”. Layered luminance over RGB in Photoshop CC 2014 and did some light curves work, used Carboni’s Astronomy Tools “make stars smaller”, and topped off with AstroFrame.