Horsehead from the Queensland Astrofest and 3 nights at Leyburn

[firstlight]

Well, I had a great time this weekend at Leyburn. I captured some Horsehead over 2 nights to add to the data I captured last month and the month before at the Queensland Astrofest. Need to say this Wow, astronomy 3 times in three months :eyepop:

This is the first rough process of the data stacked in PixInsight from all four nights. I wasn't as careful as I could have been on the best night (last night) so the focus was off and that has made some artefacts around the stars, at least that is what I think is going on. Needless to say there is a lot more work needed to be done.

At this stage I cant think how much data and the full details... I think something like 6 x 300 sec 1600 + 6 x 600 sec 1600 + 6 x 600 sec 1600 + 14 x 600 sec 1600, about 290 minutes? I'll have to check, might be more might be less.

In spite of the artefacts I'm pretty chuffed... More data next month? :shrug:

[strongmanmike]

Ah processing that hard earned data from a dark sky weekend...what great excitement :thumbsup: That result is really quite good, well done :thumbsup:

Mike

[gregbradley]

An excellent Horsehead image.

Greg.

[RickS]

A very nice HH, Tony. Well done!

[DavidTrap]

Nicely done Tony!

DT

[jjjnettie]

That's a beaut little Horsie!

[naskies]

Well done, Tony - that's a great image. It was nice to have a bit of a pow wow under the stars to pass the time :)

[RB]

Great capture Tony, well done buddy.

RB
:thumbsup:

[firstlight]

Thanks Mike, I am still scratching around in the processing area, and while I am happy with the result, I think thatere is more I can do to improve it.


Thanks Greg.



Thanks Rick, I need to work out what I am doing in the stacking process, as I pretty well used the default settings, so there should be some improvements there. I found I have dark halos around the brighter stars which may have something to do with poor focus on Sunday night.


Thanks David. I enjoyed your startrail.




I had a great time too David. Thanks for your time and help over the weekend. Good luck with your exams.:prey:


Thanks Andrew, I have a long way to go before I can produce your quality though.

[firstlight]

Here are those halos I was talking about. Any ideas?

[David Fitz-Henr]

Very nice Horse Tony, well done!

The brighter regions may be a little over-stretched, causing bright halos as well as some of the brighter nebula being a little burned out (eg. centre of the blue reflection nebula).

[astronobob]

A mighty fine image Tony, dig the colors and the contrasty horsey stands out heaps, Top result :thumbsup:

[multiweb]

Beautiful colors. Well done. :thumbsup:

[lazjen]

Like the colours, like the horsehead. Nice.

[TimberLand]

Like minds, I just couldn't resist the Horse Head myself and had to get the old camera going again. But mine is no match for that data, well done, great colours.

Focus, focus and focus again. And I still don't listen to my own advice.

Top job Tony.

Justin

[Ross G]

Great looking Horse Head Tony.


Ross.

[firstlight]

Thanks Bob,Marc and Chris. The colours just came to the fore and I felt that they seemed most natural.


Thanks Justin. Do you think that the dark halos in the crop I posted have to do with the focus or the stacking parameters? I haven't had a chance to do a repro as yet.. It may take some time to get back to it... maybe after the next dark weekend and more data? :D


Thanks Ross.

[hotspur]

That's very nice work Tony,well done-top result!

What scope did you use?

[TimberLand]

Looks like clipped data from either the stacking process or maybe colour noise reduction. I get similar faults with LRGB and the colour smoothing too aggressive.

Is it in the original images off the camera.

Justin

[firstlight]

Thanks Chris. I used the WO 110 Megrez with a 0.8x reducer/flattener, effective fl of 524mm.


the halos were there right after the stacking. I suspect that it is either to do with the poor focus in October, or too few frames from the Queensland Astrofest, and therefore the incorrect parameters in PixInsight. I'll have another go at reprocessing in the next few weeks or so. Outside chance I will be able to do it before the meeting on Friday, but the current repro will suffice if I don't have the time.

Are you coming to the OGM Friday? Or how about the Combined Meeting at Griffith on the 25th?

[TimberLand]

After stacking, would tell me that values went to high and caused an integer value to go so high that it started back at zero.

This would be possible in basic software for stacking but PI does this in 32 bit floating point as standard so shouldn't be a problem with too higher value.

Still a mystery.

For the meeting this week I will be out of town again, but on a plus note I will be clearing and levelling the site for the observatory and a couple of concrete pads beside it instead.

Justin

[firstlight]

Well I've reproed this image again. I think the problem was that I didn't have enough subs from the Astrofest, and PI wanted to use "percentile clipping" for thiose subs, while wanting "Windsorized Sigma Clipping" for the rest (changed from one then it would ask for the other).

The long and the short of it is that I dropped the subs from the Astrofest, which were only half a dozen or so 5 minute subs, and I seem to have been able to extract a bit more detail in the bright regions. Once again the colours seemed more natural to me, although I boosted the saturation a bit to deepen the emission nebula colour.

I think I'll rest on this repro until I get more data... maybe another dark weekend at Leyburn next month? :prey:

[firstlight]

Actually looking at it again this morning I think I liked the result without the saturation boost.

Any opinions?

[TimberLand]

Nice repro Tony. I don't know which one I like the best. That is a great effort, and good catch on the clipping in the processing, imagine how hard that sort of image would have been to get 20 years ago. I was looking at some of my old film attempts in this area the other day, and yours smashes the old film out of the ball park.

I use median stacking with the old DSI to keep the random hot pixels under control. It also seems to keep the background a bit smoother, but that could just be me. A better camera might change my mind but we will see in the future.

Justin

[firstlight]

Thanks Justin. I'm fanging out to image this area again and add to the capture. The nebulosity seems to go on forever.

How did the concrete pour go? You going back to the farm this weekend, or are you able to make the Combined Meeting tomorrow night??

We have a few options for the next dark weekend, we just need to decide.

[alpal]

Hi Tony,
I think you've done an excellent job with the processing.


I assume you used:


How were you guiding it?
There seems to be field rotation.
It looks like the mount was not polar aligned.

cheers
Allan

[firstlight]

I know what you are saying, however I am guiding on Alnitak, with a side by side setup with an Orion 80mm guidescope and a QHY5. I have drift-aligned and the stars don't move out of the reticle after 15 minutes. I'm thinking there might be some flexure in the rig perhaps.

[alpal]

Yes Tony,
It's strange because the center stars are round.
Maybe an OAG would help?

cheers
Allan

[gregbradley]

I find there can be quite a difference in autoguiding accuracy depending on the star. Very bright stars are not good choices as the CCD will bloat and as the software calculates the centroid point that would be hard.
Pick a single star (not a binary which are common) mid brightness, not too bright so it is oversaturating the wells of the camera.

The first thing I do if I get worse guiding errors is pick another guide star and see how that goes. I often see errors halve.

But apart from that flexure is going to be problematic unless you use an OAG.

By the way a single run of HLVG plugin for Photoshop would enhance your image a tad. It gets rid of excess green.

Greg.