I was just finishing up some modifications to my Orion ST-80 telescope (80 mm f/5) recently when Mitche posted images from his new SeeStar all-in-one scope (here). I was intrigued by the images his rig produced by stacking a lot of ten second images.
I already wanted to test my newly reconfigured ST-80 and capture two relatively bright asteroids in its wider field of view than provided by my C8. But, after seeing Mitche’s images, I was inspired to see how deep this little scope could go using just ten second images.
After checking Stellarium, I decided on asteroids (55) Pandora and (60) Echo. (55) Pandora would be at Vmag 11.6 and (60) Echo at Vmag 12.3. Both would just fit in the 1.6° x 0.9° field of view provided by the ST-80 and ZWO ASI482 camera combo. And, as luck would have it, there were two small galaxies in the field.
Even with a nearly full Moon to the east, and my next door neighbor’s porch flood lights and backyard lights illuminating my yard from the west, I was very pleasantly surprised to see that this small rig detected the two galaxies, IC 1496 at Vmag 15.5 and IC 1492 at Vmag 15.2. They are small and faint, but their point-like smudges are definitely visible just above the background noise. This gives me hope that with slightly longer exposures I can routinely capture magnitude 15-16 asteroids with this small rig from my Bortle 7 backyard.
What you see here is a two-hour animation consisting of a series of eight images. Each image is made up of 90 ten-second subframes (900 seconds/15 minutes total integration per image). Full details follow below the pic.
October 31, 2023 04:04:12-06:04:00UT
Two-hour time-lapse animation.
Minor Planet Center Predicted Vmags: (55) Pandora 11.6; (60) Echo 12.3
8 images, each a stack of 90 @ 10 seconds. Gain 350
FOV: 93.8 x 51.5 arcmin/1.56° x 0.86° (cropped size for animation)
North up. East left.
Seeing: Poor Transparency: Good Sky Condition: Bortle 7 with nearly full Moon 70° to the East.
Telescope: Orion ST-80 (80 mm f/5) + Orion Field Flattener + Baader Fringe Killer Filter
Camera: ZWO ASI482MC
Guide Scope: SVBONY SV165 (30 mm f/4)
Mount: Celestron CGEM
Captured with SharpCap Pro
Processed with Deep Sky Stacker, GIMP
Note: 11-05-23. Originally posted image replaced with image that corrected flashing label circle on (55) Pandora.