Three images from early this morning 20-05-2024

[fwm891]

Started out just after midnight intending a quick look round and found myself packing away at four fifteen because the sky was too bright to do anything else...

My first real play with my dual Askar 120 APO set-up each has an uncooled 585MC mounted with a 0.8x reducer/flattener, a filter drawer with an Astronomic L2 UVIR cut filter plus a motorised focuser. The pair are mounted on a single platform on an iOptron CEM60.

All images have been cropped a little as I still need to tweak the alignment of the OTA's slightly, no dithering was used as that has been a headache to sync between the two scopes. Omitting the dither and both run very well together.

I use two instances of NINA have one with a 20 second start delay and the other with a 5 second delay start one and when it gets down to 5 seconds start the second and I'm usually within a second of sync. Both instances are set up the same apart from the initial delays.

So.

M13 114x 60 second subs each was set to do 60 x 60 seconds but some frames discarded due to sat trails

M27 50x 120 second subs each set to 30x 120 sec

M20 20x 120 second subs used, more were taken but discarded as the sky levels were just too bright.

All processing undertaken in PI, RC Astro BXT, NXT and SXT routines were used BXT was 'correct only' for all images. Otherwise saturation and curves transform were the main tools used for colour correction. A mask was used when needed to control the background level and inverted to control the main subject. Images were then resized and saved.

Hope you like.

[TiffsAndAstro]

Great images. Cuiv the lazy geek has a video about syncing two instances of Nina and setting one as master, other as slave in case it might be helpful.

[tomato]

Great images.👍

I have used the NINA sync function to allow dither on two scopes on a dual rig. The only drawback is you lose some imaging time over a long session as the one scope waits until both are available for the dither.

[Elp]

I don't use Nina but on multiples just leave them running, I've found using maybe 30-60s works best otherwise you loose too many minutes via the "dumb" optics. Maybe throw away over 30 mins of data, but you gain in hours/nights not needed to image.

[fwm891]

Thanks @TiffsAndAstro @tomato @Elp . Perhaps because my twin scopes are not perfectly aligned (and I doubt I'll ever get them to be perfectly pixel aligned) and my crops showed a slight rotation difference between the cameras, all of which I guess negated any need for dithering. Probably the slight rotation difference being the most effective.

I plan to make some mods to the platform this week to allow some tweaks to the alignment. I can then hopefully get that sorted during the moon's brighter phases and be ready for the next 'new moon' period!

Thanks for the comments - always welcome

 

[tomato]

I can take hours trying to align my scopes, the dual rig has a bracing plate to prevent flexing which has to be slackened off to make adjustments. I get the scopes bang on but you can guess what happens when I tighten the plate back down…

In the end I have to compromise and accept that a crop of more than a few pixels will be required. Fortunately one advantage of imaging small galaxies is that a crop will not usually detract from the image.

[carastro]

I use a dual rig but l mount them piggy back so no flex.  

I tried a side by side arrangement in the past but there was no way of adjusting the aim of the scopes with only one screw on each end to tighten them on.  Plus l found pier/tripod clash more likely which was why l changed to piggy back.  

I have the Skywatcher guidescope mount to hold the 2nd scope on which adjusts both up and down and side to side.  However l found the best way was to have a larger FOV on one scope than the other so any discrepancy can be cropped out.  

l use the basic Atik software for capture   It should handle 2 iterations for capture which it does, but l found downloading subs to a single laptop problematic as everything would “hang”.  Maybe my imaging laptop is too old or needs more RAM.  So l use a second laptop  for the 2nd camera   

 

Edited May 21 by carastro

[carastro]

No camera attached to the ED80  in this photo but just to show the piggy back arrangement.  

Edited May 21 by carastro

[carastro]

I sometimes swap out the top scope for my Samyang 135mm set up.  I don’t alter the Positioning so that when l put the ED72 scope back on it is in exactly the same position as before. 
 

 

Edited May 21 by carastro

[TiffsAndAstro]

1 hour ago, carastro said:

I sometimes swap out the top scope for my Samyang 135mm set up.  I don’t alter the Positioning so that when l put the ED72 scope back on it is in exactly the same position as before. 
 

 

Need to run this image through astrosharp  

[carastro]

5 hours ago, TiffsAndAstro said:

Need to run this image through astrosharp  

Sorry, it was a zoom in and screenshot off of a video.  

[carastro]

It this better, but you still might need to zoom in. 

Edited May 21 by carastro

[TiffsAndAstro]

12 minutes ago, carastro said:

It this better, but you still might need to zoom in. 

Apologies I was just trying to be funny

also, i have thing about wiring at the moment  I notice you use a lot less NASA space tape than I do 

Edited May 21 by TiffsAndAstro

[carastro]

Lol.  I tie it back once and the rest hangs out.  Had near disasters in the past trying to do anything more.  I know this doesn’t appeal to tidy people.  

[TiffsAndAstro]

7 minutes ago, carastro said:

Lol.  I tie it back once and the rest hangs out.  Had near disasters in the past trying to do anything more.  I know this doesn’t appeal to tidy people.  

I am not a tidy person, how dare you accuse me of that?

I think I use a flimsy usb hub instead of your your blue power box? I have it velcroed on top of my scope and I have all those leads gathered and tied at the base near the dovetail plate.

Purely because I think any wires dangling down even my balance/guiding.

Don some shades or other protective eyewear and stare at the magnificence below

[carastro]

1 hour ago, TiffsAndAstro said:

I think I use a flimsy usb hub instead of your your blue power box? I have it velcroed on top of my scope and I have all those leads gathered and tied at the base near the dovetail plate.

Blue power Box?  That’s a blue dovetail 

The two items on the eyepiece tray are cigarette lighter splitter for cameras and EFW and dew straps   The other item is the dew heater controller.  I am very sophisticated lol.  

Edited May 21 by carastro

[carastro]

You should see what l use to protect the laptops from the damp.  That would win an award for innovation and tackiness. 

Edited May 21 by carastro

[carastro]

@fwm891

Sorry to hijack your thread Francis, some very nice images you produced

[skybadger]

20 hours ago, tomato said:

I can take hours trying to align my scopes, the dual rig has a bracing plate to prevent flexing which has to be slackened off to make adjustments. I get the scopes bang on but you can guess what happens when I tighten the plate back down…

In the end I have to compromise and accept that a crop of more than a few pixels will be required. Fortunately one advantage of imaging small galaxies is that a crop will not usually detract from the image.

I'd be interested in seeing that braced playe. I use one fixed and one on an adm adjustable plate and have spent time getting them bang on only to flip it across the sky and find it tens of arcseconds out. Maybe that's not so bad. 

I second the Nina dithering master/slave setup. Voyager supports array mode but you trade multi-camera support for multi-target support unless you write some external scripting.

 

[skybadger]

20 hours ago, carastro said:

I use a dual rig but l mount them piggy back so no flex.  

That's no guarantee  ! 

 

If you tandem mount them side by side you can shim them and lock them down and get similar fields. 

 

[TiffsAndAstro]

10 hours ago, carastro said:

Blue power Box?  That’s a blue dovetail 

The two items on the eyepiece tray are cigarette lighter splitter for cameras and EFW and dew straps   The other item is the dew heater controller.  I am very sophisticated lol.  

Not sure how I saw a blue power box on accessory tray