7 replies to this topic

[Mike Spooner]

Awoke at 2 AM local time and felt good enough to try and get Tethys shadow using the 11" f/5.7 Newtonian.

Wow! First look using a 3mm Radian (529x) was stunning. I had barely tweaked collimation on a Jupiter moon yesterday morning before shutting down and I guess it didn't hurt. Anyway, I booted up the laptop and focused in the ZWO224MC and 5x Powermate and captured seven 20K vids (3-4-minutes each). Used 6.8 to 13 ms exposures and gain from 480 to 520 (IIRC). Only spent an hour and went back to bed without even a cursory look since this was my second early get up in a row. 

 

Anyway here are some early results after good sleep using my less than elegant processing skills.

I really pushed the processing but I think I have evidence of Enceladus and its shadow - my processing is probably limiting the data but it appears about right on my planetarium program. If it is, I'd be pretty happy to get this with an 11"!

 

Sorry for so many images but the seeing was very nice. I again did not see single Perseid (and I did try to look occasionally).

 

Mike Spooner

 

UTC 09_12   8-13-24; 50% stack.

 

 

UTC 09_15; Probably my best "normal" processing, 50% stack.

 

 

UTC 09_21; 30% stack.

 

 

UTC 09_24; 15% stack and crops of this image.

 

[alnitak22]

Wow! I’d say that scope has a pretty decent mirror! 

[Mike Spooner]

Wow! I’d say that scope has a pretty decent mirror! 

Thanks! I have certainly enjoyed it for over two decades. Looking at the images I wonder if there is a hint of Encke at the ends of the rings. Could be a sharpening artifact I suppose. Especially since the rings are so closed up. 
 

Forgot to mention that the seeing was so good I’m pretty sure I occasionally saw Tethy’s shadow on the screen during the captures.

 

Mike Spooner

[alnitak22]

Maybe a hint of Encke in the first shot?

[Mike Spooner]

Maybe a hint of Encke in the first shot?

Maybe but hard to tell for sure. As much as I pushed the processing, the Cassini division doesn’t even look curved. Still, it’s a lot of fun to explore the capabilities of backyard equipment today!

[Kokatha man]

Clearly very nice seeing Mike - Tethys comes out in the "pushed" images but of course it is much harder to evince than its shadow...I'll reserve my judgement re Enceladus at this time of the day for me. It is of course far more challenging than the larger moons regardless.

[Mike Spooner]

Clearly very nice seeing Mike - Tethys comes out in the "pushed" images but of course it is much harder to evince than its shadow...I'll reserve my judgement re Enceladus at this time of the day for me. It is of course far more challenging than the larger moons regardless.

Thanks, Darryl. I’m not convinced about Enceladus myself but I do think I might see a bit of the shadow in the 09_21 image from the 30% stack. Might be wishful thinking. I still have a couple stacks to process and if I get gumption enough to animate a gif that could be helpful I suppose. As I noted I’m definitely limited in my down and dirty processing style but was pretty excited to get such nice seeing in the midst of our monsoon season. I joke with my wife about my ‘telescope aerobics’ fitness program! 

[Mike Spooner]

Well I processed a couple of remaining clips and as much as I'd like I just can't convince myself that Enceladus is showing. But Tethys and its shadow certainly put on a decent show. I'll add a couple of 30% stack images but again it is too easy to fall for sharpening artifacts when pushing the processing this hard. Fun to try though!!

 

Mike Spooner

 

UTC 09_30 image.

 

 

UTC 09_33 image.