This view of ω Centauri has the same field of view as
most of my other pictures of globular clusters. This
allows a fair comparison of apparent diameters of
globular clusters on the thumbnail page.
Hover over the picture for an annotated version
Date: 16 and 18 January 2026
FOV: cropped to 45' × 30'; the angular size of NGC 5139 is about 55'
Rotation: 0.328°
Telescope: Askar FRA300 pro (300mm f/5 Petzval)
Guiding: ZWO ASI120MM mini mono guide camera,
SVBony SV165 Mini 40mm f/4 guide scope
Computer: ASIair pro Raspberry Pi
Mount: ZWO AM5 harmonic drive
Camera: ZWO ASI6200MC Pro Cooled (-10°C) Color CMOS with gain 100
Pixel size: 3.76 μm
Resolution: 2.594 arcsec/pixel
Frames:
16 January 2026: 9 taken with Optolong L-Ultimate filter
18 January 2026: 16 taken with Optolong UV-IR cut filter
Stacking: twenty-five 300 second frames using Pixinsisght
Calibration frames: 20 dark, 20 flat, and 20 bias each session
Total Time: 2 hours 5 minutes
Processing: Pixinsight – SPPC, DBE, SPCC, BlurXT, NoiseXT, DynCrop → Linear
MStr, GHS, HST, PMath MStr + GHS + HST →
Stars, HDRMST6PhLm, Sat, Crop
Location: Corzones Draw Ranch near Terlingua, TX
