Soul Nebula Hubble Palette

[Rodd]

I am usually glad when I decide to collect SII after processing a bicolor version, and this is no exception.  I added 77 300sec SII subs to my recent bicolor Soul Nebula.  I was having a mysterious guiding issue.  It turns out, my system is back heavy due to not being able to slide the OTA forward far enough on the saddle plate because the focus motor hangs off the side and impinges on the saddle plate.  I read somewhere that if a scope is back heavy, the center of gravity of the RA axis is pushed down the counter weight shaft especially when the scope slews upward.  Sure enough, I slid the last counter weight down to the end of the shaft (despite agonizing over a serious moment of inertia issue) and what do you know--it did the trick.  It turned rms errors of .9-1.2" to .5"--surely good enough for imaging at 2.46".  The resultant FWHM plummeted.  Unfortunately this was only for the SII channel--so there is room for improvement

FSQ 106 EDX 4 with .6x reducer and ASI 1600 with Astrodon 3nm Filters: H4 144 300 sec; Ha 44 5 sec; OIII 70 300 sec; SII 77 300sec - A little over 24 hours

Two versions--not sure which I like better.

Edited October 19, 2022 by Rodd

[simmo39]

V nice Rodd. Think the first one just has the edge but I think both are good.

[Rodd]

54 minutes ago, simmo39 said:

V nice Rodd. Think the first one just has the edge but I think both are good.

I question if #1 is pushed a tad overmuch.  The stars are certainly worse 

[simmo39]

3 hours ago, Rodd said:

I question if #1 is pushed a tad overmuch.  The stars are certainly worse 

The stars a little worse but not that bad. The detail in the nebula looks that little bit better in version 1. But i am using my poor old eyes.

[Rodd]

30 minutes ago, simmo39 said:

The stars a little worse but not that bad. The detail in the nebula looks that little bit better in version 1. But i am using my poor old eyes.

I think you are tight. I have switched the final to the first.  I am considering RGB stars.  

[scotty38]

Very nice....

Re the balance question, can't you turn the OTA so the focuser is toward the top and it doesn't hit the saddle plate when slid forwards?

[Rodd]

5 hours ago, scotty38 said:

Very nice....

Re the balance question, can't you turn the OTA so the focuser is toward the top and it doesn't hit the saddle plate when slid forwards?

Hmm…turn it upside down?  Never thought of that. I am not sure. Can that be done?  Is it advised?

[scotty38]

10 minutes ago, Rodd said:

Hmm…turn it upside down?  Never thought of that. I am not sure. Can that be done?  Is it advised?

Can't see why not, I've seen it done many times.... In fact I only have to look on my own pier 🙂 🙂 

I turned my GT81 upside down for this very reason.

[Rodd]

1 minute ago, scotty38 said:

Can't see why not, I've seen it done many times.... In fact I only have to look on my own pier 🙂 🙂 

I turned my GT81 upside down for this very reason.

Wow.  Thanks. I will do that this weekend    

[scotty38]

Having said that, if you think about it, rotating the focuser achieves the same thing if you didn't want to rotate the whole tube for any reason.

[Rodd]

2 minutes ago, scotty38 said:

Having said that, if you think about it, rotating the focuser achieves the same thing if you didn't want to rotate the whole tube for any reason.

That would mean me removing the focuser and reattaching it, something that I will not do. Rotating the whole scope is the way  to go.  Don’t know why I (or anyone else, including starlight instruments).  

[scotty38]

ok no problem but I thought the FSQ had a rotatable focuser so was just a case of undoing a thumbscrew?

[Rodd]

10 minutes ago, scotty38 said:

ok no problem but I thought the FSQ had a rotatable focuser so was just a case of undoing a thumbscrew?

It has a rotating camera angle adjuster.  Not sure about the focuser.  

[scotty38]

Ah ok I see, that was my misunderstanding then... Back to the original idea then 🙂

[Rodd]

26 minutes ago, scotty38 said:

Ah ok I see, that was my misunderstanding then... Back to the original idea then 🙂

You could be right. Not a thumb screw though. There are screw’s covered in wax. People switch gov users all the time so it probably can Be rotated.  Any reason that would be preferred over turning the ota?

[scotty38]

Nope not really, especially if it's not easy, in fact ease would be the only reason.

[Rodd]

2 hours ago, scotty38 said:

Nope not really, especially if it's not easy, in fact ease would be the only reason.

I think I will do it. Right now by sliding the last counterweight to an fro I can keep rms errors to about .6-.65.  For imaging at 3.46 that is ok. But I wonder how rms errors of .3 would impact the image.  

[Rodd]

6 hours ago, scotty38 said:

Nope not really, especially if it's not easy, in fact ease would be the only reason.

I knew there would be something.  I use the AP vario guider and it is designed to attach to the focuser not the rings so there is no flexure. Astro physics designed a bracket that firms up the scope. Well, on TAK scopes, there is a shoe that they make that attaches in the spot that a finder scope sits. This shoe is the only way to connect the vario guidescope to a tak. It would be below the OTA if I flipped the scope or just the focuser.   It’s the little things in this hobby.  When I upgrade my camera to the ASI 2600, I will be going for an oag that will be interchangeable as a single unit between the fsq and reducer and TOA and new flatner.  Then I will flip the scope.  Thanks gif the idea. I would not have thought about it on my own