NGC1499 - The California Nebula - With Extra Hydrogen Beta

[PhotoGav]

Here is my image of NGC1499 - The California Nebula:

Shot details are:

William Optics Star 71, QSI 683-WSG8, Baader 1.25" filters, HEQ5 Pro

RGB: 24 x 300s each

H alpha: 13 x 1800s

H beta: 16 x 1800s

Total Integration Time: 20.5 hours

This one didn't come out how I had in mind. It was an experiment with a newly acquired Hydrogen Beta filter. I had hoped that the HBeta filter would introduce some blue to the image, but however I tried to process this one, very little blue colour was inclined to come to the party! Anyway, once I resigned myself to the lack of blue, I discovered that the HBeta does add an extra dimension to the image. The HaRGB image was very red and pretty flat really. The introduction of HBeta to the Blue (30%) & Green (20%) channels has given the nebula some highlight areas, which definitely help the image. Am I delighted with the HBeta filter and likely to recommend it to a friend? Not really!

As ever, your thoughts, comments, criticisms and general opinions are very welcome.

Clear skies,

 

[Knight of Clear Skies]

Any chance you could post up the H-beta channel please, just to see what it looks like?

[Barry-Wilson]

A very accomplished image Gav with a bold nebula and lovely textured structural detail.  Great work, with your nebula just floating within your frame.

Your star shapes are spot on and so you have your mount and technical control of data capture mastered.  I really like it Gav and it certainly has that 'unprocessed' feel and mark of a first class image.

 

[michael.h.f.wilkinson]

Very nice image. It does make the saturation of the nebula less prominent. I do wonder if simply blending a little H-alpha into the G and B channels wouldn't give a very similar result, as I would expect the distribution of both emissions to be very similar

[Knight of Clear Skies]

9 minutes ago, michael.h.f.wilkinson said:

I do wonder if simply blending a little H-alpha into the G and B channels wouldn't give a very similar result, as I would expect the distribution of both emissions to be very similar

Quite possibly, but I've been wondering if when there is more than one ionizing source might there be more H-beta closer to the brighter ones?

[michael.h.f.wilkinson]

2 minutes ago, Knight of Clear Skies said:

Quite possibly, but I've been wondering if when there is more than one ionizing source might there be more H-beta closer to the brighter ones?

That is possible of course. I would be very curious to do a precise comparison of the distributions of the H-beta and H-alpha emissions

[PhotoGav]

Thank you for your kind words Barry - this project nearly beat me, so it's particularly good to read approval! The next project that I am going to process, hopefully tomorrow, is the Altair's first light... finally!!

Knight & Michael - thank you for your comments. Here are the two Hydrogen images:

Hydrogen Alpha:

Hydrogen Beta:

They have both been stretched and processed, the HAlpha more than the HBeta. The HBeta was fairly weak and you can already see the noise creeping into the image. You can clearly see that the Hydrogen Beta is more present in the brighter dust fronts of the Hydrogen Alpha image. I think that the effect of the HBeta in the G & B channels is consequently more subtle and focussed on those fronts as compared to using the Hydrogen Alpha data in those channels.

I can make the two unprocessed images available to you if that would be of interest.

[PatrickGilliland]

Nice work Gav - it is very bold but it works very well.  The combined channels lift the nebula away form the background and create nice depth and texture.

Paddy

[Maximidius]

That's a beautiful rendition of the California Nebula 

[PhotoGav]

Thank you Paddy & Maximidius.

[ollypenrice]

I love the Ha but would be tempted to put the H beta time into LRGB or 0III. The background sky around this target is interesting and I can't really see how the H beta is going to play against the stronger reds with similar structure.

Olly

[PhotoGav]

15 minutes ago, ollypenrice said:

I love the Ha but would be tempted to put the H beta time into LRGB or 0III. The background sky around this target is interesting and I can't really see how the H beta is going to play against the stronger reds with similar structure.

Olly

Quite! Still, it has been an interesting experiment to see whether the H Beta filter is a worthy addition to the imager's filter carousel. Or not...

As for that blue colour I wanted, you are right, a bi-colour with OIII probably would have delivered that.

[simmo39]

A stunning image

[Knight of Clear Skies]

12 hours ago, PhotoGav said:

Here are the two Hydrogen images:

Thanks for posting them up. Flicking back and forth between the two images it looks like all the bright regions match up, I suspect a more gentle stretch of the Ha would look almost identical to the H-beta in this case. Reading up on the California Nebula the ionizing source is almost certainly the runaway star Menkib. As it's one of the hottest visible stars it probably overwhelms anything else in the vicinity. I suspect it would be a real challenge to find a DSO that looks significantly different in Ha and H-beta, multiple ionizing sources and shading from dust might help but I'm not sure.

Cracking image with plenty of detail anyway, I always look for the circular feature on the left.

[PhotoGav]

14 minutes ago, Knight of Clear Skies said:

Thanks for posting them up. Flicking back and forth between the two images it looks like all the bright regions match up, I suspect a more gentle stretch of the Ha would look almost identical to the H-beta in this case. Reading up on the California Nebula the ionizing source is almost certainly the runaway star Menkib. As it's one of the hottest visible stars it probably overwhelms anything else in the vicinity. I suspect it would be a real challenge to find a DSO that looks significantly different in Ha and H-beta, multiple ionizing sources and shading from dust might help but I'm not sure.

Cracking image with plenty of detail anyway, I always look for the circular feature on the left.

Thank you. Yes, it makes sense that the H Beta is in basically the same area as the H Alpha as the Beta is only pumped up Alpha. Oh well, an interesting experiment which is partially successful. I think that the beta data has added highlights to the alpha data, giving the image a bit more depth and definition. As for Menkib... it's a monster of a star!

[Davey-T]

Excellent result Gav, always good to experiment if you have the time / clear skies, interested in this as I'm working on the same subject in HST using Star71 and QSI683 just hoping for some clear moonless nights as usual.

Dave

[ollypenrice]

I wouldn't want to knock the H beta filter since it gave me my first book credit - a book about String Theory in Dutch.   Say no more!!! 

Olly

[laudropb]

Very spectacular image.

[PatrickGilliland]

10 hours ago, ollypenrice said:

a book about String Theory in Dutch

 So the second edition will be double dutch which is what string theory is to many!