1220 replies to this topic

[ekallgren]

Good to hear that you made it safely, we all hope that the scope made the trip without any trouble. I hope the weather will cooperate for the "Eclipse" . 

Enjoy!!

[Mert]

From my experience going back and forth with the RC8, the collimation

very likely will be fine.

The most important thing after 2007 miles is that you arrived safely!

Hope you enjoy the eclips!!

 

Regards,

Mert

Edited by Mert, 01 April 2024 - 01:52 PM.

[Dark_Knight18]

I have always used SharpCap as my aquisition software for my reflector.  Trying to setup NINA for use with my RC8.  SharpCap lately seems to be changing a number of things with black Levels and Gain.  I am a bit frustrated by the changes.

 

 

N.I.N.A Setup Question

 

Should I use the full F/L of 1625 in NINA? I have posts where other RC8 owners recommend 1600mm or 1610mm.  Recommendations?

[Dark_Knight18]

More NINA questions:

 

 

Save file settings- FITS or PI format XISF?
What Image Save file patterns are normally used?

Under AutoFocus> Curve Fitting Strategy> should I use Parabolic instead of Hyperbolic since I am using an RC scope design?

[DevonRob]

I have always used SharpCap as my aquisition software for my reflector.  Trying to setup NINA for use with my RC8.  SharpCap lately seems to be changing a number of things with black Levels and Gain.  I am a bit frustrated by the changes.

 

 

N.I.N.A Setup Question

 

Should I use the full F/L of 1625 in NINA? I have posts where other RC8 owners recommend 1600mm or 1610mm.  Recommendations?

Start with 1625 - then use plate solving to get yourself positioned. Once done, grab a sub, and in ASTAP (or on astrometry.net) you can measure the actual FL and re-enter that as the value. It may differ from say 1610 to 1630, which is fine. Any more than that and your secondary may have been moved (centre screw) and it could be worth tuning that back into the normal range. FWIW - mine was 1621 (now reduced tho to 1306mm) . NINA was fine at 1625, but plate solving is a bit quicker with the exact FL in place.

[DavesGalaxy]

Here's another image I captured with my RC8 and nateman_doo's brilliant primary decoupler!

 

https://www.astrobin.com/lmaor8/

 

 

 

Clear Skies!

Dave

[nateman_doo]

2000 miles... and This was the extent of the eclipse footage:

https://i.imgur.com/V9gzOx4.mp4

 

[ekallgren]

Hopefully you had other things to do while you were there, and the trip wasn't a complete bust. 

[nateman_doo]

Oh i have every scope I own on different targets, time lapses and other stuff. In no way am i going home empty handed. Just stinks to drive that for for 3 seconds. But it I what it is.

[ekallgren]

Great Attitude!

On another note, how did the collimation hold up on the drive down?

Edited by ekallgren, 08 April 2024 - 10:55 PM.

[nateman_doo]

Great Attitude!

On another note, how did the collimation hold up on the drive down?

I swore I posted that??  I must be losing my mind, so little sleep I have been getting on this trip.  To answer your question?  FLAWLESS!  

[Mert]

Great!! What exposure time was that?
That is textbook perfect!!

Edited by Mert, 09 April 2024 - 02:57 AM.

[nateman_doo]

Thanks =)

400 seconds in my go-to for that scope.

Edited by nateman_doo, 09 April 2024 - 08:18 AM.

[Mert]

Thanks =)
400 seconds in my go-to for that scope.

Was that ASTAP image done with your RC8??
Very low numbers

[nateman_doo]

Yea, they are low.  But yea, that's with the RC.  

[nateman_doo]

Im finally back home.  Lots of data to process.  

[nateman_doo]

I have been thinking for a while when you mentioned how low the numbers are that ASTAP may be grabbing hot pixels with its stars for the flatness test.  Since I got back home, I put the scope back on the atlas mount (guiding was amazing btw) and picked a new target, NGC 5906, the Splinter Galaxy.

 

Still held collimation on the drive home over 4000 miles/6400KM) :

 

 

Zooming in, the stars still look great, but I think its also grabbing noise/hot pixels:

 

 

But ultimately the stars look good, so thats all I really care about.  

[Mert]

Impressive James!!

When I have the collimation dialed in on a steady night, taking

a sub of 30 seconds for example never gets me below 2.8!

This using the RC8 with a CCDT67 reducer at 0.635"/pixel

Also the seeing was a reasonable 1.22" on average

 

[Edit] After collimation thing look very good and centered but when I

mount the Falcon rotator there seems to be some tilt introduced by it.

Will have to check collimation even better but I fear I won't reach those

low numbers of yours James!

Edited by Mert, 21 April 2024 - 12:06 PM.

[nateman_doo]

I took off the debayering in ASTAP, and here is the image:

Really is a great looking shot.  Almost looks like a wide field refractor.

 

 

 

And still, gives me similar readings:

 

Im using the Starizona APEX L flattener/reducer.  I had no love for the CCDT67, it certainly reduced the fov and made it faster, but it did nothing to flatten the field.  Was not cheap at all, but as the expression goes..."Buy once, cry once".

 

edit: above is a 400 second sub through the Antlia RGB filter, so that could be why the stars are smaller, its not wide open, but the shots I took before were no filter when I was in Texas, and I still got the same numbers on a 400 second sub which was this image:

Edited by nateman_doo, 21 April 2024 - 12:16 PM.

[nateman_doo]

ok, NOW we got to the bottom of things:

 

I rebooted and after the debaying off, ASTAP  got a much more accurate reading and wasnt grabbing so many things:

 

12%

 

I thought it was too good to be true in that regard.  I adjusted the scope with the cheshire using the spider vain mounts as a reference, and I must have messed with the debayering functions of ASTAP.  While I was ultimately pleased that using the mounts to help as a reference, I never got accurate data to do a star test from that point on.  So I still believe it held the collimation from that time (since everything looks the same) 

 

I dont have the collimation I thought I had.  Its probably a half a screw turn off, and I have to ask myself do I want to mess with it or not...  I feel morally obligated to mess with it after humble bragging about perfect collimation.  

Edited by nateman_doo, 21 April 2024 - 12:30 PM.

[Mert]

IMHO it looks good!  How is it that the numbers have gone up suddenly

Same setup?

Exposure time?

Here is an ASTAP analisis from a couple days ago with my RC8:

 

 

Attached Thumbnails

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Edited by Mert, 21 April 2024 - 04:17 PM.

[nateman_doo]

I just kept analyzing the same frame.  No difference in anything.  So bottom line up front, using my standard laser method of getting the secondary and focuser aligned, then using the farpoint astro 2" cheshire aligning on the spider vane bases got me to 12% without any further adjustments.  

 

So I am going to give my top left screw a hair adjustment in either direction and see what it is.  Cue clouds for the next few weeks. 

[Dark_Knight18]

Are there any owners of Moonlite Focusers who use the Starizona ED-L reducer/flattener?

 

My question is- how do you have your imaging train setup that allows for the reducer/flattener to be installed inside the drawtube?

 

 

Thanks Brian 

[nateman_doo]

The reducer/flattener is 2" OD. It should slide into any focuser.

[joecpoon]

 

Thank you, nateman_doo.  Received the adapter today.  Beautiful work!