IC 289 (PK 138+02.1, PN G138.8+02.8) Planetary Nebula in Cassiopeia. Taken Dec. 10, 28, 29, 2018
and Jan. 01, 2019. Imaged with Starlight Xpress’ SX-825 camera and a Celestron EdgeHD 9.25 at f10,
on a Losmandy G11/Gemini mount. The H alpha and OIII subframes were 15 minutes binned 1x1, while
the RGB subframes were 4 minutes binned 2x2, resulting in the following total exposures L:R:G:B =
(HA+OIII):(R+Ha):(G+OIII):(B+OIII) (min) = (390+360):(64+390):(64+360):(64+360). This image is
displayed at 0.57 arc-seconds per pixel. Captured with Nebulosity, calibrated, sigma combined in
Iris with other processing using PixInsight LE and Photoshop CS. North is up.