Swansea Astronomical Society Blog

A Coronado PST was used to take a 4,600 frame SER using a Player One Apollo-M-Mini camera with Astro DMx Capture and some 20% of the frames were then stacked in Autostakkert!4, wavelet processed in Registax and further processed in Pixinsight's Solar Toolbox with false colour being applied. At the same time a Dwarf Min fitted with a solar filter was used to take 264 FITS images in white light which were similarly stacked and processed, with PIPP being first used to correct the orientation. The Ha image was then resized to match the WL image's apparent size to show a comparison snapshot of our star in both Ha and white light side by side.

Chris Bowden

posted by Chris B  # 9:28 PM 0 Comments

The Sun in white light through a William Optics Zenithstar SD Doublet 66mm APO refractor fitted with an ICE ND100000 glass solar filter. Captured by AstroDMx Capture with a Touptek Astro AE676C camera. The best 90% of 500 frame SER file were stacked in Autostakkert!4, wavelet processed in waveSharp3 and further processed in GIMP3.

Steve Wainwright and Nicola Makin

posted by astroimager  # 6:26 PM 0 Comments

The Sun in H-alpha light through a Coronado Solarmax II 60, BF 15 H-alpha scope. Captured by AstroDMx Capture with a Touptek Astro AE676C camera  in HDR 16 bit mode. The best 80% of 1000 frames stacked in Autostakkert!4, wavelet processed in waveSharp3 and further processed in PixInsight and GIMP3.

Steve Wainwright and Nicola Mackin

posted by astroimager  # 5:18 AM 0 Comments

In August I published a detailed blog article on how to make HOO images from the dualband images produced by smartscopes like the Dwarf smartscopes, the Seestars, (and other OSC cameras with dualband filters), mainly using GIMP by decomposing the RGB image produced. Of course the method presented there equally applies to H and O3 data from a monochrome camera.

Bicolour images contain O3 and H data (although on some occasions S2 and O3 data can be used)

It makes sense to use just H and O3 data if the object being imaged contains little or no S2.

Heavy elements like sulphur require massive stars (many times the size of our Sun) to form. Low-to-intermediate-mass stars end their lives as planetary nebulae without ever synthesizing heavy elements.

Objects such as the Orion Nebula (M42) and the Eagle nebula (M16) display all three main emissions: hydrogen-alpha, doubly ionized oxygen, and ionized sulfur (H, O3, and S2, respectively), and are very suitable for SHO type tricolour, and, of course bicolour false colour images.

Planetary nebulae and some supernova remnants contain so little sulphur that it is usual to skip the S2 filter entirely, opting instead for a dual-band H-alpha (H) and O3 filter with a One-Shot Colour (OSC) camera, or just H and O3 filters with a monochrome camera to create an HOO image. Because the progenitor stars of these objects were not massive enough to fuse heavier elements, or because the structures are dominated by specific shock-front emissions, the sulphur-II (S2) signal is practically non-existent or adds little unique structural detail.

The following categories and specific nebulae are ideal for strict HOO (Hydrogen/Oxygen) imaging:

• Planetary Nebulae (e.g., Ring Nebula - M57, Dumbbell Nebula - M27, Helix Nebula - NGC 7293): Created by dying, Sun-like stars, these objects lack the mass to produce significant amounts of sulphur. Their emissions are overwhelmingly dominated by intense O3 shells and H cores.

• The Squid Nebula (Ou4): This very faint nebula is inside the Sh2-129 hydrogen emission region. The Squid itself is purely an O3 structure, so there is no reason to capture SII data for it.

• The Veil Nebula Complex: As a supernova remnant, the Veil has distinct, overlapping filaments of H and very bright O3. While a trace amount of S2 is present, it almost perfectly mimics the Hα structure and offers negligible new contrast or detail.

• The Soap Bubble Nebula (PN G75.5+1.7): An extremely faint planetary nebula that glows almost exclusively in O3 , making an SII filter redundant.

posted by astroimager  # 4:54 PM 0 Comments

Taken with a Coronado PST and an Apollo-M-Mini camera: A 20% stack of an ~ 5,000 frame SER file captured with Astro DMx Capture, with the frames stacked in Autostakkert!4, wavelet processed in Registax, processed/coloured in PI's solar toolbox and finished off in Adobe Lightroom.

Chris Bowden

posted by Chris B  # 12:22 AM 0 Comments

This image of the Lion nebula was captured with a Dwarf mini scope through a dualband filter.

The RGB image was decomposed into its H and O components: Red = H; Blue and Green = O. Combining the blue and green channels into the Blue channel, discarding the old green channel and normalising the Red and new Blue channels (bringing them to similar brightnesses). The bicolour HOO rendered image was constructed.

The Lion nebula HOO

Chris Playle

posted by astroimager  # 9:19 PM 0 Comments

During the members viewing and imaging night held at the Brian Stokes Cygnus Observatory on the 3rd October 2026, the main scope (a 12" Meade LX200) was used to image Saturn at its closest approach to Earth during opposition. Using AstroDMx Capture approximately 10,000 separate images were taken in the early hours of the 4th October using a Player One Apollo-M-Mini camera fitted with a x2 Barlow lens. Four separate SER files were taken covering the period of 03:11 to 03:24 using region of interest. The separate SER files were then concatenated using PIPP with 10% of the resultant SER file images stacked in Autostakkert!4, wavelet processed in Registax and finished off in Adobe Photoshop. Two other SER runs were done to expose for the nearby moons Mimas and Rhea which were then composited in with the processed image of the planet to produce the wider field image.

Chris Bowden

Saturn at opposition with 12” LX200: 10% of 9,794 frames with Apollo-M-Mini x2 Barlow (Autostakkert/Registax/Photoshop)­­­­

Composite of Saturn and two of its nearby moons Rhea (left) and Mimas (right)

posted by Chris B  # 6:21 AM 0 Comments

During the members viewing and imaging night of the 3rd October 2026, a Dwarf Mini was used to take ~1.5 hours of the Triangulum Galaxy M33. The scope was configured in EQ mode to save the individual 60s FITS files, which were then stacked and processed using Pixinsight to reveal the spiral arms within the cosmic dust of the galaxy.

Chris Bowden

posted by Chris B  # 6:03 AM 0 Comments

Several members enjoyed a fine clear night at the Brian Stokes Cygnus Observatory to see Saturn at opposition through some of the society's larger aperture scopes which gave some great close-up views. Several other deep sky objects were also observed including the double star cluster in Perseus, the Andromeda Galaxy M31 and the Great Orion nebula M42 with M33 and the Iris nebulae imaged by two members using both traditional and smart scopes. The night concluded with some superb views of the waning last quarter Moon which looked spectacular at higher magnifications.

Chris Bowden

posted by Chris B  # 5:58 AM 0 Comments

The California nebula taken with the Dwarf mini in EQ mode at 60s exposure and gain 80. 100 images were stacked. Processing in Stellar Studio, Star Net++ and Gimp 2.10. 

M33, the Triangulum galaxy taken with the Dwarf mini in EQ mode at 60s exposure and gain 80. 200 images were stacked. Processing in Stellar Studio, Star Net++ and Gimp 2.10.  

Chris Playle

posted by astroimager  # 4:57 PM 0 Comments

93% Moon Captured by AstroDMxCapture for Linux with a Touptek Astro AE676M mono camera and a Stella Mira 66ED APO refractor. The best 80% of the frames in a 1000 frame SER file were stacked in Autostakkert!, wavelet processed in waveSharp 3 and further processed in GIMP3.

Steve Wainwright and Nicola Mackin

posted by astroimager  # 5:04 PM 0 Comments

M17 Captured by AstroDMxCapture for Linux with a Touptek Astro AE676M mono camera and a Stella Mira 66ED APO refractor. 1.5h total exposure; 30 minutes on each of Ha, O3 and S2 filters. Stacking and part processing in PixInsight, further processing in GraXpert, SASPro and GIMP3. 

Hubble palette.

Steve Wainwright and Nicola Mackin

posted by astroimager  # 4:48 PM 0 Comments

The Bubble nebula and M52 Star cluster taken with the Dwarf mini in EQ mode at 60s exposure and gain 80. 200 images were stacked. Processing in Stellar Studio, Star Net++, Gimp 2.10 and Lightroom.  

Chris Playle

posted by astroimager  # 4:40 PM 0 Comments

3.25 hours of SHO data of the Tulip nebula (Sh-2 101) taken on the night of the 28th September 2026 with a Sky-Watcher Esprit 80 triplet refractor fitted with a field flattener using an ASI 533MM Pro camera and EFW. Data acquired with NINA and integrated/processed in Pixinsight.

Chris Bowden

posted by Chris B  # 3:09 PM 0 Comments

On the night of the 26th September 2026 an ASI 533mm Pro camera and EFW were attached to a Sky-Watcher Esprit 80 triplet refractor fitted with a field flattener to image the Crab nebula (M1) and the Pacman nebula (NGC 281) during partly hazy skies. Over the period of several hours sufficient data were accumulated to blend with similar amounts of data taken previously with the same equipment. For the Crab nebula around a two hour integration of SHO data was processed using a combination of HOO and SHO blending using narrowband normalisation in Pixinsight. Despite the small data set I drizzled at x2 which coaxed out a lot more of the background filament data, as well as the central "heart" shaped structure of M1. For the Pacman nebula (NGC 281), some 1.3 hours of new SHO data were merged with a similar amount of data taken previously with the same equipment to produce a new SHO image. This was then combined with a 90 minute RGB data set taken previously to produce a combined 4 hour integration employing x2 drizzling to maximise detail.

Chris Bowden

posted by Chris B  # 2:10 AM 0 Comments

On the night of the 26th September 2026 a Dwarf Mini was placed on the ground in Alt/Az mode to take some deep sky and lunar images during partly hazy skies. The Veil nebula and the Pleiades were both imaged using 15s subs and due to field rotation, were limited to a maximum of 45 minute runs. The full harvest moon was also imaged on two occasions through passing cloud, with a short number of frames and a larger set taken. Despite the conditions some reasonable results were obtained from such a tiny scope with stacking done internally within the scope itself.

Chris Bowden

posted by Chris B  # 1:53 AM 0 Comments

Harvest Moon with the Seestar S50

The Sun in H-alpha through thin clouds. Captured by AstroDMx Capture with a Coronado solarmax II, 60 BF15 H-alpha scope and a Touptek Astro AE676M camera. 1000 frame SER file stacked in Autostakkert!4, wavelet processed in waveSharp3 and further processed in GIMP3

Steve Wainwright and Nicola Mackin

posted by astroimager  # 8:12 PM 0 Comments

The Harvest full Moon taken with the Dwarf mini in EQ mode at 1/200s exposure, gain was set to 0 and 118 images were stacked. 

Chris Playle

posted by astroimager  # 2:23 PM 0 Comments