Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: The Thing on Oct 09, 2018, 21:05:53

Title: Yet another M42
Post by: The Thing on Oct 09, 2018, 21:05:53
There must be loads of M42s on here and all different! Taken last night (2018-10-09) after the main imaging run finished, set up and kicked off using an android tablet and bluetooth keyboard FROM MY BED at 4:00am!! I was just checking everything else had happened as planned so I didn't really think about the Trapezium overexposure problem at the time so it's a bit blown out in that section.

26x120s Gain 120 (unity) temp -20C. Stacked with Darks only in DSS 4.x, processed in Startools, resampled to half size in Irfanview (click the image to see that one).

(http://gallery.orpington-astronomy.org.uk/albums/userpics/10050/normal_M42_2018-10-08_ST_half.jpg) (http://gallery.orpington-astronomy.org.uk/albums/userpics/10050/M42_2018-10-08_ST_half.jpg)

P.S. Don't look too closely at the stars.
Title: Re: Yet another M42
Post by: MarkS on Oct 10, 2018, 06:29:49
Wow - great result for an image acquired remotely from bed!

I love the dust - there's so much of it.

Mark

Title: Re: Yet another M42
Post by: The Thing on Oct 10, 2018, 09:18:46
Thanks Mark. The dust is something else in this one, don't know why it came out so well, it's only 42mins of data. Shame the bright areas are blown out so much, I'll have another go next clear night. Last night was very clear and I could've added some short subs to fill in the missing stuff but sleep is precious so I didn't wake up to change target. The next version of APT will do multiple targets with plate solving etc. so automation of multiple taget will be possible. You can even import frames from CdC so you can assemble a plan to do mosaics. The current beta is not very stable at the moment or I'd be using it :)
Title: Re: Yet another M42
Post by: Carole on Oct 10, 2018, 09:38:00
Amazing amount of dust. 

If you did this from your bed, I presume you left everything set up and the dome open before you went to bed.  Very brave.

Carole
Title: Re: Yet another M42
Post by: The Thing on Oct 10, 2018, 09:45:42
Thanks Carole, remote access to my laptop is a a wonderful thing and the weather gods have been kind this new moon. Seeing all that dust made me get the hoover out this morning!
My previous best version done with an 1100D had hints of it but the data wasn't there. Mind you I was over the moon at the time.

(http://gallery.orpington-astronomy.org.uk/albums/userpics/10050/thumb_M42_Early_Morning_DSS_CS2.jpg) (http://gallery.orpington-astronomy.org.uk/displayimage-search-0-1582.html#top_display_media)
Title: Re: Yet another M42
Post by: NoelC on Oct 12, 2018, 10:49:02
Terrific Duncan!
The center almost has a cave like quality to it.
I've only just started using APT - not up to speed with what it can do yet.
How do you manage flipping?  Can APT re-aquire, or do you just plan ahead?

I left mine running on Tuesday night on Cygnus and went to bed as the sequence had 5 hours to run and Sat24 had it clear all night - of course it flipped 2 hours later losing the target totally.
Title: Re: Yet another M42
Post by: The Thing on Oct 12, 2018, 11:10:03
Hi Noel thanks for the kind comments.

I never let the scope flip. I have automatic meridian flip turned off in EQMOD (in the Toolbox). My TS1506UNC f4 Newtonian scope on NEQ6 will track at least two hours past meridan at most declinations and I have the balance set so worm mesh is not affected much at the crossover point.

APT can reacquire. Sort of. In the latest versions (get the latest Beta, it's what I'm using)) you can script in a command to do a GoTo++ to recenter the target and it will automatically stop and start guiding (check box at bottom of Guide dialogue) for you as well. However I don't think there is any way of the script knowing the mount has reached the meridan so you would have to build a script which would take a number of subs before meridan is reached, script a GoToOffset or GoToAltAz (might be easier) to trigger a flip and then a GoTo++ to recentre the target based on the previous subs centre (orientation shouldn't matter). You could post a request on the APT forum Ideas topic asking if a meridian detection and conditionally running a script (you can branch scripts) could be added somehow. I think flips are best avoided though and generally will change target around the time it would be needed.

HTH

Duncan
Title: Re: Yet another M42
Post by: ApophisAstros on Oct 12, 2018, 12:33:12
Quote from: NoelC on Oct 12, 2018, 10:49:02
How do you manage flipping?  Can APT re-aquire, or do you just plan ahead?
The new APT is going to auto flip apparently ...watch this space.
At the moment i park scope wait for target to move over the meridian and reacquire.
Roger
Title: Re: Yet another M42
Post by: The Thing on Oct 12, 2018, 13:47:29
I had heard that but don't think it's in the forthcoming v3.6.
Title: Re: Yet another M42
Post by: Carole on Oct 12, 2018, 14:07:34
QuoteP.S. Don't look too closely at the stars.
Just noticed your PS, I hadn't looked at the image enlarged.  What do you think has caused that Duncan?

Carole
Title: Re: Yet another M42
Post by: The Thing on Oct 12, 2018, 21:08:43
I think Duncan caused most of it! I suppose mostly it's because of some dodgy subs stacked in DSS. I'm going to do the whole thing again in Pixinsight at some point, I've got 6 other sets of data waiting to be dealt with.
Title: Re: Yet another M42
Post by: Fay on Oct 14, 2018, 14:51:51
Cant believe its only 42 mins Duncan!!