old_eyes

Here are the top right hand corners of the image straight from WBPP and then after DBE and BX. Straight from WBPP. Only STF and Dynamic Crop applied With DBE and BX. The second centre is clearly visible in the data straight from WBPP and BX separates it into two stars. But, the effect is even there in a single sub! It must be something in the optics, unless we are getting a reproduceable jitter during a single 120 sec exposure? So I don't think BX is going to help in this case

What did you set star sharpening to to get the best result?

OK. I will try some experiments with lower settings, but these 'artifacts' are found in the original linear data out of WBPP. They are fully separated from the major star for low brightness stars covering only a couple of pixels, but in brighter larger stars they look like a bump on the side. Not a classic egg shaped star, but a sense of a separate centre. I will upload some examples when I get a moment (currently WBPPing data from another run on the same pier. Those 35mm sensor files are big!).

Hmm! Interesting. I tried BlurXterminator with AI4 instead of AI2, but it did not improve things. Closer examination shows that both filters show tiny ghost stars next to the brighter stars. These give the impression of out of shape stars, but are artifacts of the stacking process. I don't understand than yet, but the seem to arise from misregistering of some frames in WBPP in Pixinsight. Needs more investigation!

Continuing experiments with dual band filters and colour camera. Taken on Pier 5 @Roboscopes in Spain (Tak Epsilon 180, ASI 2400MC Pro, Askar Colour Magic Ha/O3 and S2/O3 filters, unguided paramount MX). 3hrs Ha/O3 and just under 5hrs S2/O3 in 120 sec subs. Processed in Pixinsight. Filters processed in dividually and then combined using PixelMath expression - "Max(0.7*HaO3, S2O3)". LocalHistogramEqualization used to emphasise the Bok globules. Cropped to about 75% of original. Pleased with this one, but suggestions for improvements gratefully received.

Good job on the Squid Olly. I have tried to get that over and over again, but so far you can see it is there, but nothing like the impact you have produced. Perhaps I need to go back and brutalise it some more!

For a wonder we had a couple of clear cold nights last week (first I have been able to use since July!). So here is a quick Fish Head Nebula (IC1795) (I needed to stay away from the moon). 7 Wells observatory - Esprit 120, ASI 533MM Pro, Mesu 200 guided mount. 2hrs Ha, 3 hrs S2, 4:10 hrs O3, all in 300 sec subs. Processed in Pixinsight using SHO palette.

Congratulations. Very nice powerful image.

Captured on Pier 5 @Roboscopes (Tak Epsilon 180, ASI 2400MC Pro, Askar ColourMagic Ha/O3 filter, unguided Paramount MX). 73 x 120 sec subs for 2hrs 26mins integration time. Processed in Pixinsight. Continuing experiments with the dual band filters. Lots of glare from Alnitak and Alnilam (even more dominant in an OSC image). Alnitak is controlled to some extent by the strong Ha surrounding it. Alnilam is against a dark sky. I could not find a way of controlling Alnilam without making the whole image look weird and unbalanced, so I left it. This version is slightly cropped from the original.

Oooh! Lovely, lovely dust! And even better in the full frame version. How long was the integration time?

Roboscopes also have an O3/S2 filter on this pier. So I am trying that out to double the amount of O3 I have captured (lower QE for camera in the blue) as well as trying to add some sulphur signal.

Congratulations on achieving Associate status with the RPS! You must be very pleased to have the quality and artistry of your work recognised by the professionals. As thew number of images I am pleased with steadily climbs, I have been thinking about photobooks as a way of making them available to friends and family. At the moment I am having them photoprinted by processing houses and stuck in a scrapbook. Lots of digital photography processing houses offer photobooks and the prices are not excessive. Could you add a photo of your book to the thread?

Two pane mosaic of NGC 1499 taken on Pier 5 @Roboscopes (Tak Epsilon 150, ASI 2400MC Pro, Askar Colour Magic Ha/O3 filter, unguided Paramount MX). Upper pane 90 x 120 sec subs. Lower pane 63 x 120 sec subs (focus problems led to a significant number of rejected subs). Processed in Pixinsight. The O3 signal is weak in this image. Others have noted that if your O3 signal is strong and balances the Ha, a sual band filter with an OSC camera gives a good result. If the Ha is strong, then leakage into the green and blue channels can overwhelm the O3 signal. That is what seems to be happening here (OSC RGB Response and Dual Narrowband Filters - Experienced Deep Sky Imaging - Cloudy Nights). Compare this result with a previous version done with a mono camera and narrowband filters: Much better separation of Ha and O3 signals. For this target the Ha/O3 filter gives a nice but less informative image.

I have read "First Light: Switching on Stars at the Dawn of Time", and isn't it a great read? Thanks for pointing out the issue in the early universe. I did not immediately make that connection. I looked up a few papers (most of which were way beyond me) and gleaned a few points. Population 3 stars are often massive, and there is something called the Jean's density at which gravity overcomes any push back from thermal motion or magnetic fields. Models also suggest that there is enough energy dissipation from several processes involving H2, H and ions to allow the cloud to reach the Jean's ratio. Some authors suggest that HD may have an important role to play as it has a dipole, which H2 does not. Others say there is not enough D around to make this a viable process. So as with much of the history of the very early universe, there is no agreed view yet.

Last week, I was able to attend and online lecture organised by the Royal Society of Chemistry called "Astronomical Spectroscopy: understanding the complex chemistry hidden between the stars". Now I am a chemist with a keen interest in how the universe works, and did not expect to be surprised, but I was astonished by the latest research. Not only is there more chemistry going on than I suspected, but it is more important. This event was based on a Faraday Discussion meeting held at STSI in Baltimore in June. You can download all the proceedings here in return for registering Faraday Discussions Home-Discussion summary &amp;amp; research papers from discussion meetings that focus on rapidly developing areas of physical chemistry and its interfaces<br/><br/>Chair: Susan Perkin<br/>Impact factor: 3.4<br/>Time to first decision (peer reviewed only): 19 days (rsc.org) Webinar speakers were: Martin McCoustra, Professor of Chemical Physics, Heriot Watt University Serena Viti, Professor of Molecular Astrophysics, Leiden Observatory Wendy Brown, Professor of Physical Chemistry, University of Sussex It was a pretty dense hour, but I want to pick out a couple of fascinating things that were new to me. We have now identified about 250 molecules in space using spectroscopy. from small radicals and ions like OH, through simple molecules like water, methane and ammonia, to complex things like amino acids - precursors to life. Unsurprisingly the biggest diversity is found in high density regions like collapsing dust and gas clouds where stars and planets are forming (Nice animation here: Exploring Star and Planet Formation (webbtelescope.org)). Most of the work is done at IR and radio frequencies using a variety of space and terrestrial telescopes, and JWST is a game changer. We can now study the molecular composition and distribution in distant galaxies. The first amazing idea is that molecules are crucial in maintaining the rate of star formation. Atoms, yes, dust and gas and general stuff, yes, but molecules? Turns out that the collapse of a gas cloud under gravity is limited by the presence of charged ions that create magnetic fields that oppose the force of gravity. Carbon monoxide ice and water ice in space form solid crystals on dust particles that also have an electric field that can mop up the ions. Killing the magnetic field and allowing the cloud to continue to condense until a star can light up. And for small stars like the sun, thermal motion in the cloud can stop gravitational condensation. But molecules are great at radiating energy in the IR, so the excess thermal motion energy can be radiated away, the cloud cools, and the stars can form. The second idea is that chemistry happens very effectively on the surface of dust particles, driven by starlight, stellar winds and cosmic rays, and shock fronts (pressure and temperature waves). This produces a chemical soup, that includes all the bits and pieces we need for the formation of life. Carbonaceous meteorites are known to contain such a chemical soup, and even more remarkably, the molecules have the same chirality (handedness) as found in life on earth. Many more complex molecules exist in mirror image forms, and life only uses one form (Getting it wrong can be very bad. Thalidomide was synthesised as a 50:50 mix of the two mirror forms. One was the active drug, and the other was toxic - leading to all those birth defects). Another interesting idea is that different drivers are important at different points on the timeline towards formation of stars and planets. Cosmic rays are energetic enough to get chemistry going with simple molecules in a very cold dense gas cloud. As the star starts forming dust particles covered with a layer of ice have a catalytic surface that can form more complex molecules, and then as the star lights up it emits high energy jets (Herbig-Haro objects). These shocks allow high energy reactions to happen - increasing the range and complexity of molecules that can form. I apologise if this is all horribly boring, but I was just fascinated and surprised by the range of molecules that can form in space, and just how important they are cosmologically.

I am using a Dahua starlight cctv camera (Dahua IPC-HDW4231EM-ASE 2MP IR Turret Network Camera (citysecuritysystems.co.uk)). It is POE and IP enabled, so easy to install and use. I can access from anywhere over my local network. It has an IR illuminator, but this can be turned off. Could be useful to give night time security when you are not imaging. Found it to be reliable and easy to use, and perfectly able to view the interior of the observatory with the roof open just by starlight, or any remaining glowing LEDs you have not covered up. Had it for a couple of years so model has probably been superseded.

Beautiful image Dave! Love the way you have achieved such a large panorama, whilst dropping in data from more detailed imaging. Something I have read about, but never attempted. Thank you for the inspiration.

Very nice indeed. You have lots of detail there, and the cropped image is particularly nice.

I can only await with bated breath yet another “vast mosaic” from the team at Les Granges!

Two-panel mosaic of the Heart and Soul nebulas in Cepheus captured on Pier 14 @Roboscopes in Spain (Tak Epsilon 130, ASI 6200MM Pro, unguided Paramount MX). Approximately 1.25 hrs Ha, 3 hrs O3 and 2.5 hrs S2 for each panel in 300 sec subs. Image processed in PIxinsight and cropped and downscaled from the original. I had a troublesome colour gradient I could not seem to fix so some of the faintest detail is lost, but still pretty pleased with it. Palette is a roll-your-own I like that @Vlaiv explained to me

Good point! I had not thought of that explanation. Would make sense of what we see. Generalised low-level emission from large clouds of Hydrogen, with that nice brighter ‘outlining’ of the Veil. High-res spectroscopy should tell, but that is way beyond me.

It certainly looks like it, but I have been wrong before!

Yes, it is trying to work out what is Ha in the vicinity (there's a lot about in that part of the sky), and what is part of the complex. I may be kidding myself, but I see a partial outer ring of Ha emission. Something outside the typical features we image but tracking the general shape of the Veil. It's fun when you see something you hadn't noticed before!

I have not seen the extra Ha in the background before. Some of it looks like a true part of the remnant. Interesting.

2-panel mosaic of the ever popular Veil Complex. My first try with a dual-band Ha-O3 filter on a colour camera. ~50 x 300 sec Ha-O3 on Pier 5 @Roboscopes in Spain (Tak Epsilon 180 f/2.8, unguided Paramount MX, ASI 2400MC Pro).