November 2023

Welcome to Hank’s November 2023 Astrophotography Blog. About a month after I dropped my telescope and shattered the corrector plate, Celestron returned the repaired OTA and all looks good! I put a belt around the telescope and secured the belt to the mount, so hopefully I’ll not repeat that particular trick again. What could possibly go wrong with a complex piece of very fragile equipment, run by software that defies explanation where you generally use it in the dark? That’s astrophotography!

During the “break” I got some advice on purchasing an Off Axis Guider (OAG) and camera. Chris again came to the rescue and by the end of November I had the OAG in place, the camera focused (there’s another story….), and after about 5 hours of phone calls with Chris, everything was almost ready to go. Early December will find me doing the final calibrations and I should be up and running….

So, what’s an OAG? Basically, it is a small prism in the telescope’s optical train, that catches a bit of the sky, sends it to a separate camera that locks on a couple of stars, with a piece of software called PHD2 (Press Here Dummy, Too) that sends a message to the telescope every time the telescope veers just the tiniest bit from those stars, and tells the telescope to move to get back on track! So, why would you want an OAG? It’s all about getting long exposures. For the last 3 years I have been mostly doing “live stacking” of 8 to 30 second exposures for a total of about 10 minutes. With the OAG it is my hope to start collecting longer (2-5 minute) exposures for hours of total exposure time and get much better details in my photos. Stay tuned! We’ll see if I can pull it off….. Here’s what an OAG looks like when you peer down the tube that goes to the telescope and the camera. It’s the squarish shiny prism thing dropping down from the top.

In the meantime, this month, I’ve been taking 30 second exposures for about 30 minutes to get more familiar with the SIRIL post processing software. There are a few BHAS members who are trying this software out and it has been encouraging to see the results they are getting, too. Here’s what I captured this month and processed with SIRIL:

SIRIL is starting to show promise, as I have tried to capture the Tadpoles Nebula using my old “live stacking” methods and never had much luck, and even with “short” 30 second exposures, details are coming out!

I also thought I’d try to catch up on a couple of planets: Saturn and Jupiter. The blown-out image of Jupiter shows 4 of its moons. This image caught Io just as it was going behind Jupiter, and appears as just a bump.

Until next month, Clear Skies. -Hank