The Heart of the Orion Nebula

[Screwdriverone (Chris)]

Hi Everyone,

Well, I have been a busy beaver, made myself a light box I did!

Took me most of the weekend, but it was worth it, now I can take flats whenever I want, yeehah!

So, to test, I decided on ol' faithful, M42, The Great Orion Nebula. The seeing on Sunday night seemed to be amazing! VERY clear and steady after some shocking previous nights....

I am still working out the kinks of the alignment when using my pier, it seems it takes me even longer to set up and tear down, but it will be good when I build the obs and leave everything set up when it is fine tuned.

So, after about 3 hours of tinkering and having dramas with PHD crashing everytime I used the ASI120MC as an ST4 guider, I went back to pulse guiding with EQMOD and captured some Orion goodness.

An hour's worth of stacked 5 min images revealed a nice dirty big dust donut on my CLS filter which almost ruined my night, until I took some flats at 1.5 sec which gave me an average of about 25,000 ADU (at least I thought so as Nebulosity reported on Auto a range of 18,000 to 32,000 which made 25,000 right in the middle - is that right? I hope so). Anyway, stacking with the flats in DSS and VOILA, no more dust donut and NO vignetting, YAY!

I remembered to take 12 x 10 sec shots of the core for separate stacking and overlay in PS, which I did, as well as a new set of 5 min darks at -10c to add to my bias frames. I EVEN took some dark-flats as well! Shock horror.

Therefore, after all this, I had DSS give me a GREEN light as I had ALL my calibration frames loaded for once

So, off to Photoshop with the result and remembered how to layer mask and gaussian blur the core and selective inverted layer mask for the sharpening, I finally had a result that I think turned out pretty nice.....so here it is.

Total 1 hour (12 x 5 mins - main) and 2 mins (12 x 10 secs - core) of exposures with Atik 314L+ through a Skywatcher 8" newtonian reflector on an HEQ5Pro (on my pier ) guided with PHD using EQMod and an ASI 120MC. Stacked in DSS and processed in Photoshop CS5 only.

Higher resolution 6Mb PNG file here

Probably one of the nicest results I have achieved, taken from Sydney, so I am pretty happy with how it all came out. Of course, tips, tricks or critiques are welcome as they will only help me to get better.

Thanks for stopping by and taking a look.

Cheers

Chris

[Rod771 (Rod)]

That's nice and smooth Chris! The core is nicely tamed too Its a good feeling when results go your way, especially when you have to remember how to do things after a couple of cloudy weeks

I actually have Pixinsight crunching away on some M42 data taken from Sunday /last night too. Sunday was great! Very clear as you say and quite cool - good for the 60da

Looks like the light box was a success, well done!

[Screwdriverone (Chris)]

Thanks Rod,

Yeah I am happy with how smooth it came out, no noise reduction needed and hardly any stretching as the histogram was so full it didnt need much at all.

I am stoked at how well the light box turned out, I thought it may be a little dim as I used 4 x 10000mcd Clear LEDs and the obligatory 430 ohm series resistors (after I blew one up when testing without the resistor - DOH), but in the dark the front aperture with the white perspex was beautifully illuminated and even the whole box glowed. I will need to tape that up if I want to use it at IISAC as it is a bit bright, I used foam core vinyl clad sheet from Officeworks which was easy enough to work as it was stiff, but hard to cut with a sharp knife so I used tin snips and the jigsaw.

All up, with the perspex, LEDS, dimmer, switch and 12V plug, it cost me pretty close to $50, so I am chuffed it works so well.

Flats rock at removing the vignetting and uneven gradients across the image as well as the dust bunnies, so now i don't have to be so careful with trying to remove ALL the bits that may settle on the CLS filter, PLUS I get to see more of what I image without having to do contortions to remove the uneven gradients.

M42 is pretty bright though, so this one was relatively easy to process. I have some galaxy subs that I will try out soon, so I will see if I can reproduce the process.

Cheers

Chris

[Larryp (Laurie)]

Very nice Chris

[Screwdriverone (Chris)]

Cheers Laurie and thanks

Chris

[DavidU (Dave)]

You have done well Chris. Doing well now aincha

[strongmanmike (Michael)]

Well, ya've kinda butchered the stars a little Chris... , especially the fainter ones... but the core blend is well handled and given your trials and tribulations, not to mention your pristine Andes like location I'd say it's a success and congrats on building the light box too

Mike

[Screwdriverone (Chris)]

Originally Posted by DavidU

You have done well Chris. Doing well now aincha

Thanks David, I am getting there, slowly, but its working

Originally Posted by strongmanmike

Well, ya've kinda butchered the stars a little Chris... , especially the fainter ones... but the core blend is well handled and given your trials and tribulations, not to mention your pristine Andes like location I'd say it's a success and congrats on building the light box too

Mike

DAMMIT Mike! I knew you would pick those up....! I honestly don't know what the issue is there with the faint stars??? I used to think it was DSS and the stretching on it I did on the stacked result before saving to TIFF, but this one didnt get DSS stretched and I basically didnt stretch it much at all in Photoshop as the histogram was full already?

I am thinking it may be the camera as I have compared it to some DSLR shots through the same scope and the DSLR fills out these stars beautifully.

I did get some slight drift on the subs from some dodgy alignment coz I was getting impatient, but each sub, while some were better than others, looked quite good with the seeing and guiding I was getting.

So, in a nutshell I dunno? Yes, they look butchered, but the nebulosity and smoothness win this battle, ESPECIALLY with a fully calibrated (for once) image, so I am relatively happy. I intentionally didnt process the stars to fix them up in Startools, simply because I wanted to keep it au naturel as possible, so inevitably, they are pretty shoddy for reasons I am yet to figure out.......

Machu Pichu my backyard AIN'T, so I no complain about this sort of result

Thanks for the comments Mike

Cheers

Chris

[Ross G]

Great looking photo Chris.

Nice closeup. Your best photo of late.

You're handling the light pollution well.

Ross.

[Screwdriverone (Chris)]

Thank you Ross,

As Mike pointed out (fairly), I have some issues with the faint stars, probably from undersampling with the camera as it is only 1.3MP and I have a fairly narrow FOV on my 1000mm FL scope with a small chip. At least this is what I think it could be? CCDCalc says it is at 1.33 arcsec/pixel so I don't know if this is good or bad? All I know is the nebulae come out nice, but the stars always seem to be "empty" and a little bit shoddy, even on the FITS files straight out of the camera...

I appreciate the compliment though, progression is a good thing

Cheers

Chris

[Tony_ (Tony)]

Nice image Chris!

The stars (especially the fainter ones) look very similar to a problem I had last year. None of the subs looked like that - just the final image. It turned out to be the settings in DSS. I never knew exactly what parameter caused it. I reset the DSS to the default settings, re-registered and stacked the subs and the problem was gone. I reprocessed a lot of images and they all became better. Maybe worth a try?

Regards,
Tony.

[Screwdriverone (Chris)]

OK, sounds like a plan Tony,

I have tried stacking in Nebulosity also but didnt get very far, I might do as you suggested and give it another crack.

Cheers

Chris