IC434 Horsehead Nebula

[joshman (Josh)]

Well, the weather has not been anywhere near as good as I would have hoped it would be this summer, but I finally had enough mostly clear nights to get a usable amount of data on the magnificent Horsehead Nebula.

I have very distinct memories of first seeing this at a small astro get together organised through IIS when I first got into the hobby, ~15 years ago. I had no idea what I was doing, had a Skywatcher Gold ED80, and the base model HEQ-5, and was using a Canon 350D. One of the other attendees, had a fantastic little goto contraption called "the Cube." My memories of it are limited, and not much more than what I've put here, but I very distinctly remember seeing a "live" image of the Horsehead nebula that night. So this DSO has some very distinct memories attached to it.

It took me several years, and a whole lot of life journey, but I first (and last) imaged this back in 2019, and I've been wanting to get back to it since, but weather, life, and work got in the way for a few years. All up I've managed to collect just under 10 hours of good Data

Processing this was a very convoluted affair, as I couldn't quite find the right way to combine the HaRGB in PI to give me the result I was looking for. I could process this as a HaGB, or as a RGB, but neither gave me the result I was looking for. The level of crisp details in the Ha Stack was incredible, but the overall colouring of the was much nicer in the RGB stack. So I ended up creating a stack of each, processing them separately, then combining them at the end to create my final image.

The final workflow I settled on was:

Individual Channels:
GraXpert
LinearFit to Ha
BlurXterminator

Create 2x stacks using ChannelCombination. RGB and HaGB.

HaRGB and RGB stacks:
SPCC
StarXterminator (kept RGB stars, discarded HaGB stars)
NoiseXTerminator
Stretch with GHS
CurvesTransformation
Combine using PI toolbox script
More CurvesTransformation.

Stars:
Stretched using GHS
SCNR and invert>SCNR to clean star edges

Stars re-combined into final image with PixelMath.

Overall I'm pretty happy with how this turned out, I think a better result could be obtained with a lot more RGB data to better balance the Intensity of the Ha channel. But this will have to do until this weather lifts.

Click here to see it big on Astrobin

Thanks for looking, and Clear Skies!

[AlexN]

Thats phenominal Josh! Really nice!

As you say, the Ha chanel is dominating the image a little, but Ha dominates majority of Banards loop, so that's not unexpected at all.

I love the detail in the few reflection nebs surrounding the flame too - Thats always my gauge of a good NB/RGB mix of the horsehead area - if those nebs look good, the image is pretty well balanced!

[gregbradley]

Superb Josh!

I just imaged the same framing over the last few nights at my dark site.

It is the best framing for this object.

Greg.

[joshman (Josh)]

Originally Posted by AlexN

Thats phenominal Josh! Really nice!

As you say, the Ha chanel is dominating the image a little, but Ha dominates majority of Banards loop, so that's not unexpected at all.

I love the detail in the few reflection nebs surrounding the flame too - Thats always my gauge of a good NB/RGB mix of the horsehead area - if those nebs look good, the image is pretty well balanced!

Thanks Alex! I don't know if i'd just never noticed them, or i'd only ever seen bad images, but i was surprised by the number of reflection nebula in and around this target. I definitely want to capture more data on this, hopefully I'll have enough good weather without that moon this season.

Originally Posted by gregbradley

Superb Josh!

I just imaged the same framing over the last few nights at my dark site.

It is the best framing for this object.

Greg.

Thanks Greg! This framing is certainly the best that i could see; it's a classic for a reason!
Though, I've got a few ideas to mix it up a touch - I hope i have enough good weather this season to try it out.





I'm working through a re-process of this. On a whim I dropped all of my subs (good and bad) into WBPP in Pixinsight and let it pick and choose what to use. It gave me an extra 3.25 hours of data, and that little bit of extra data definitely shows in the stacks of each channel.