My week with M42 & PixInsight : A learning curve

[feilimb]

I recently obtained a SW ED80 DS Pro second hand via this forum and got a chance to give it first light recently. I have been dabbling with the DSLR (unmodified Canon 450D) and my Celestron 8" SCT up to now but never got around to taking flat frames or dark frames until this week.

About a week ago I captured about 90 minutes of 3.5 minute subs (plus darks and flats) on M42 in my first attempt at this target.  I took 10 x 30s exposures, and 10x10s exposures also in case I managed to use them for the core area.

Over the past week I have gone through a bit of a learning curve with PixInsight, using tutorials from Harry's Astro Shed (http://harrysastroshed.com/pixinsight/pixinsight video html/pixinsighthomenewbie.html ) to learn some of the basics, David Alrich (https://www.youtube.com/watch?v=yB0_g58CQBY ) to learn how to do some HDR composition for combining different exposure lengths for the core of M42.  I also had a look at Trapped Photo's tutorial but got lost about 1/3 of the way down (http://trappedphotons.com/blog/?p=642 ).

I also found this tutorial from 'Eor Equis' very useful as my final stacked image in DSS kept coming out totally green: https://www.youtube.com/watch?v=6mqHpcbzlBU.

The 4 images below show what were the final results I achieved on 4 different nights, with the last image incorporating the shorter exposures and HDR composition to see more detail in the core.  It has been a good learning curve anyhow and I'm looking forward to starting to capture some more targets, it will be hard to avoid shooting M31 on my next clear sky..

 

[saac]

felilimb these are excellent; thanks for sharing the references you used.  I played around with the trial version of pixiinsight about a year ago for my first proper attempt at M31 then set it aside, but now I need to get around to purchasing the full version. I like the way your final image doesn't look overly processed.

 

Jim

[Demonperformer]

Processing is a steep learning curve, indeed, but you have produced some excellent results for your first attempts. Well done!

[mikey2000]

Very good! I'm walking the same path at the moment.  PI is definitely powerful but mindbendingly hard to get started with....

[ngwillym]

Feilimb -thanks for posting this -especially the references - I'm trying to do the same thing, so far only used Lightvortex tutorials, but got stuck.

I'm hoping the addititnal stuff you point to will get me sorted.

Neil

 

[jjosefsen]

Those are excellent! Very well done.

 

[feilimb]

28 minutes ago, ngwillym said:

Feilimb -thanks for posting this -especially the references - I'm trying to do the same thing, so far only used Lightvortex tutorials, but got stuck.

I'm hoping the addititnal stuff you point to will get me sorted.

Neil

 

Good stuff I hope some of the links are useful. I found David Aldrich's tutorial on YouTube very good and he has another one about 45 minutes long on his general workflow process for DSLR image processing, it is also well worth a watch (and rewatch..!).  Looks like clear skies here in the south of Ireland tonight, so I'm hoping to start my next project - I'm not sure yet what the target will be, maybe the whirlpool galaxy, or maybe something a little larger..

[newbie alert]

Awesome...you learned very quickly...fantastic image 

[Sunnieboy]

Excellent shots, I am carrying out the same process at present with Nikon D5500 and SW 200 no guiding.  Lots of lights via intervalometer, max 30 secs at present, but really struggling with the software DSS/Registax/Gimp. However with these recent clear (and cold) nights I thought I would get as many frames as I could and struggle on with the software later.

Have trialed ATP in house at it were for longer exposures but not yet ready for live action.

Regards

Sunnie

[feilimb]

Actually after taking all of my 3.5minute exposures, when I then took the 30s exposures I couldn't get over how much was actually in the 30s ones.  In a way the 30s exposures seem to have a good balance between not being too blown out in the middle but still having good detail in the nebula - I'm guessing the main advantage to going with longer exposures (for M42) is for capturing the fainter detail towards the 'suburbs' of the nebula and the faint nebulosity around the accompanying 'running man nebula'.

To capture the 'Trapezium' (the 4 stars in the center of the Orion nebula), I finally took 10 x 10s exposures - but after looking at them properly a day later I could see that was actually too long and they still kind of blow out.  It looks like to have captured those 4 central stars properly I should have used something like 3-5s exposures.

We ended up having snow showers yesterday evening, which finally cleared to immaculate skies and frosty conditions by 11pm... but with work in the morning I didn't manage to start the next project yet

@Sunnieboy by the way there is one more link I did not post above, which gave the DSS stacking settings posted on a blog, when I used those settings myself the stacked image finally started to look right.  I'll see if I can dig up the link later on.

[Sunnieboy]

Feilimb

Thanks would appreciate the link.  Know what you mean re Trapezium difficult to expose correctly, four bright 'smudges' at 30 secs ISO 400/800, will try less exposure.  Still playing with different ISO's to identify the best for the Nikon.  Used the Bahtinov mask for focussing with the 'live view' option and zoom and was surprised it seemed to work well. Better than my earlier manual attempts.

Sunnie

[feilimb]

@Sunnieboy Here is that link I mentioned for the DSS settings I ended up using in case it is useful:

https://www.star-watcher.ch/image-processing/deepskystacker-settings/

[Sunnieboy]

Many thanks Feilimb, will check out tonight.

Sunnie

[jjosefsen]

On 12/02/2018 at 10:00, Sunnieboy said:

Excellent shots, I am carrying out the same process at present with Nikon D5500 and SW 200 no guiding.  Lots of lights via intervalometer, max 30 secs at present, but really struggling with the software DSS/Registax/Gimp. However with these recent clear (and cold) nights I thought I would get as many frames as I could and struggle on with the software later.

Have trialed ATP in house at it were for longer exposures but not yet ready for live action.

Regards

Sunnie

Good idea!

I think you really should look at something other than GIMP for your post processing.

It doesn't ahve to be PixInsight, it could be Star Tools or some other software.

[Sunnieboy]

jjosefsen

 

Thanks I will check out Star Tools, new to me.  I have looked at PI but I am so early in my learning about AP that I want to be convinced it is for me before I spend real bucks.

Regards

Sunnie