An attempt at the Trifid over two nights. 31x20 minute subs with a QHY8 and an RC8 on an EQ6.
During the first night I noticed a bizarre elongated "star" creeping across the nebula over subsequent exposures (at bottom right of attached crop of one sub). Turned out to be the asteroid Hermentaria, according to Cartes du Ciel. Largely disappeared in stacking thankfully, as it was quite bright (mag 10.8 apparently).
The perils of imaging near the ecliptic I guess - on the second night there was a similar fainter asteroid nearer the edge of the frame. Though I've never knowingly encountered that problem before!
Was hoping to get more detail of the neb than my last attempt a few years ago and also the jet. I think, with an optimistic eye, the jet may be just visible.
Comments appreciated. Full res on Astrobin or more browser friendly here.
Very nice Paul,
Plenty of detail too.
Have you tried making an animation with the various subs with the asteroid? Should be an interesting project...
Bo
The jet is definitely visible. The blue reflection nebulosity is well captured. (We tend not to see it in NB) A very fine shot.
We'd love to see a version without data rejection so that we could see the asteroid dotting its way across.
(The other day we did an asteroid in Virgo with an airbus or similar flying through the image about once an hour, and for some reason their flight path seemed to change with sidereal time, tracking the galaxy. You don't want to see that!)
Very nice Paul,
Plenty of detail too.
Have you tried making an animation with the various subs with the asteroid? Should be an interesting project...
Bo
Thanks Bo. I've tried Mike n Trish's suggestion re a trail (see attached). An animation would be good too when I get a mo.
Quote:
Originally Posted by alpal
Hi Paul,
nice image.
I want to do the Trifid but the weather has been bad in Melbourne.
Thanks Allan. We had a few good - though cold - nights in Adelaide. Cloudy now again though.
Quote:
Originally Posted by Placidus
The jet is definitely visible. The blue reflection nebulosity is well captured. (We tend not to see it in NB) A very fine shot.
We'd love to see a version without data rejection so that we could see the asteroid dotting its way across.
(The other day we did an asteroid in Virgo with an airbus or similar flying through the image about once an hour, and for some reason their flight path seemed to change with sidereal time, tracking the galaxy. You don't want to see that!)
Thanks. Hopefully was a Virgin plane in Virgo!
Nice thought re doing one without data rejection. I've just stacked the first night's images in the attached - half of which were not included in the other one as the FWHM was shoddy. You can see a couple of gaps in the trail where I've stopped to refocus! And the trail gets wider towards the SE (it was going NW to SE) as my FWHM deteriorated!
You can see a couple of gaps in the trail where I've stopped to refocus! And the trail gets wider towards the SE (it was going NW to SE) as my FWHM deteriorated!
That's great! The other asteroid is also clearly visible now.
An excellent Trifid Paul, all the main elements are well executed, it looks believable and natural, in fact my first impressions were of Marcus Davies award wining version
My bits of feedback would be that it looks like it could do with some more selective sharpening, the jet is well revealed, in fact it is two jets, the long one angles back into the field while the smaller one angles out of the field and you can see this effect in your image nicely
That's great! The other asteroid is also clearly visible now.
Aah. Hadn't seen that one! The other one I mentioned was from the second session - that data not in that stack. It's clearly a busy area for asteroids!
Quote:
Originally Posted by strongmanmike
An excellent Trifid Paul, all the main elements are well executed, it looks believable and natural, in fact my first impressions were of Marcus Davies award wining version
My bits of feedback would be that it looks like it could do with some more selective sharpening, the jet is well revealed, in fact it is two jets, the long one angles back into the field while the smaller one angles out of the field and you can see this effect in your image nicely
Thanks Mike. I tried to go easy on the processing (for once!) - e.g. no decon even. But will try some more sharpening selectively as you suggest.
Mind you to be fully honest I confess to attempting decon, but just couldn't find any settings where it did good things to the image without also doing bad things
A fine shot indeed Paul some advice......back off on noise reduction and try and retain the dynamics of the central dust and core area.....colour looking good.
A fine shot indeed Paul some advice......back off on noise reduction and try and retain the dynamics of the central dust and core area.....colour looking good.
Thanks Louie. Will take a look at noise reduction - though I don't think much at all was applied to that central area.
Very good rendition Paul! Colours are spot on IMO. I can just see the jets (usually the first thing I look for ) - excellent!. Now add some proper unsharp masking and the the dust lanes will pop.
Very good rendition Paul! Colours are spot on IMO. I can just see the jets (usually the first thing I look for ) - excellent!. Now add some proper unsharp masking and the the dust lanes will pop.
Thanks Marcus and Louie and Colin.
What I tried was the dark structure enhancement script in PixInsight. Dialled back quite a bit from default settings.
Have you tried making an animation with the various subs with the asteroid? Should be an interesting project...
Bo
Bo, thanks for the suggestion. Uploaded a quick process of the 15 relevant frames as an animated gif on Astrobin. Not great processing, but best I could do with the Process Container in PixInsight and my limited skills!
As well as Hermentaria, there is another asteroid that Placidus noted at the top of the frame, and a very faint one a bit ahead of Hermentaria.
