Hughsie

I have never experienced this before and hope that I have just missed something in the calibration process.

Below is a rather poor unprocessed but calibrated image of NGC4236. Below it is the Master Dark taken later the same day. Both images have the same exposure time, gain, offset, binning and sensor temperature. As you can see the RGB image has both a positive (light) and negative (dark) ‘glow’ on the right hand side. However, when you look at the Master Dark image it is almost like it is horizontally inverted to the RGB image.

In calibrating the lights I did try inverting the dark frame about the horizontal so the pattern matched but PixInsight kicked out an error saying the images did not match. Has anyone seen this before and what was the outcome.

Separately the flats have not corrected, and I see there is copious material on the forum regarding that so I will dive in.

I started this image on 21st January 2021. At 4am the next morning I arose to go outside and pack up my gear. That was the plan anyway.

What actually happened was I got up, blacked out and fell to the bedroom floor. In fact my head, arms and torso fell to the floor, my left foot had other plans and stayed firmly planted on the deck then released a loud crack as I turned over on it. Hospital followed, then a big boot and I never returned to M106.

Until now.

Presented in LRGB as follows;

21/01/2021 - R:G:B 3 minutes exposures (25:39:29)

26/27 Feb 2022 - L:R:G:B 2 minute exposures (130:60:55:60)

Total integration time - 14.8 hours.

Hi Rusted. There could be a linear edge from the left hand side of your text overlay heading straight up which then fades out when it reaches the left sunspot.

I really wouldn’t have said anything if you hadn’t mentioned it so don’t be too hard on yourself.

Some time ago I had a dot located on the bottom edge of my solar images and I tried for ages to process it out eventually using a clone tool. When that didn’t work I cleaned my computer screen and the dot was gone. Never overlook the obvious, clean that screen today 😊

I do like a nice open star cluster. Presented here is Messier 44 located in the constellation Cancer.

Equipment

• William Optics Z103 refractor.
• ZWO ASI1600mm Pro Cool.
• SkyWatcher EQ6R-Pro mount.
• Chroma 1.25” filters in RGB.

Data

• Exposure time 2 minutes.
• Gain 139, Offset 30. Sensor temperature -10c.
• Sub frames R:G:B (95:79:95).
• Total integration time 9 hours.

Software

• Sequence Generator Pro.
• PHD2.
• PixInsight.

Using the Luminos app and changing location to the Philippines, at 9am on 22 Feb Jupiter was slightly West of your described bearing but it was just above the rising Sun so not sure if it would have been visible. Venus had not risen at that time.

Sh2-261, Lower’s Nebula. This target faces a lot of competition from its more famous cousins located in the constellation Orion so is not a commonly photographed area of nebulosity.

Equipment Used

• William Optics Z103 refractor.
• ZWO ASI1600mm Pro Cooled Camera. Gain 139, Offset 30, Sensor Temperature -10c.
• SkyWatcher EQ6R-Pro mount.
• Sesto Senso motor focuser.
• ZWO EFW.
• Chroma 1.25” Ha, Sii, Oii, Red, Green & Blue filters.
• Pegasus Power Box.

Data

Acquired across 5th & 6th January 2022

• Ha - 36 frames x 300s
• Red - 12 frames x 300s
• Green - 12 frames x 300s
• Blue - 12 frames x 300s

Acquired across 19th & 20th January 2022

• Sii - 37 frames x 300s
• Oiii - 17 frames x 300s (clouds stop play)

Total integration time 10.5 hours.

Calibration frames - 25 flats and 25 flat darks for each channel. 50 dark frames used.

Software

• Sequence Generator Pro for session management.
• PHD2 for guiding.
• PixInsight used to squeeze the life out of the data.

Processing

• All frames were calibrated, aligned and stacked.
• Master lights were then cropped.
• DynamicBackgroundExtraction used to subtract gradients from each Master.
• Deconvolution applied to Ha master.
• TGVDenoise applied to linear masters.
• MultiScaleMedianTransform applied to each master to further reduce noise.
• RGB channels combined. MaskedStretch applied to produce Non-Linear Master. StartNet++ applied to remove RGB stars.

• Sii, Ha, Oii stretched to non-linear state using HistogramTransformation.
• PixelMath applied to combine SHO - Red Channel (Sii 80%, Ha 20%), Green Channel (Ha 100%), Blue Channel (Oiii 80%, Ha 20%).
• Further noise reduction applied using ACDNR.
• ColourMask script used to generate Red, Green, Blue and Yellow masks.
• ColourMask applied and R,G & B adjusted used CurvesTransformation.
• Contrast and Curves adjustments made.
• RGB Stars added to SHO using PixelMath.
• Star size reduction applied.
• Further curves adjustment.
• Sharpening and then a tweak to saturation.

Flaming Star Nebula

 The Flaming Star Nebula is an emission/reflection nebula and HII region ionised by the variable star AE Aurigae. It is also known as IC405, Sh2-229 and Caldwell 31. It is some 1,500 light years distant and is about 5 light years across. Research suggests that AE Aurigae is a runaway star and its proper motion can be traced back to the region of Orion’s Belt. Some 2.5 million years ago AE Aurigae and another star, Mu Columbae had an encounter with one another in the Great Orion Nebula which was so close that both stars were ejected from the region.

This objected is located within the northern constellation, Auriga and as the star passes through this gaseous region it gives the impression that the star is burning.

Data

Presented in the Hubble Palette, the following data was acquired across the nights of the 12^th and 13^thJanuary 2022.

Sii – 38 sub frames

Ha – 61 sub frames

Oiii – 45 sub frames

Exposure time 300s. Total exposure time of 12 hours. Camera Gain 139, Offset 30 and Sensor temperature was -10c.  50 darks, 25 flats and 25 dark flats were used to calibrate the data.

Equipment

William Optics Z103 refractor.

ZWO ASI1600mm Pro Cooled camera. 

SkyWatcher EQ6R-Pro mount.

Chroma 1.25” 3nm narrowband filters.

Software

Sequence Generator Pro for session management.

PHD2 for guiding.

PixInsight used for processing the image.

Final Images

I have presented this object today in three formats;

·      IC 405 with star field.

·      IC 405 in a starless field.

·      IC 405 and AE Aurigae (the star of the show) in a, well, one star field!

As usual an annotated image is included to show other points of interest in the field of view.

So named after father and son amateur astronomers, Harold and Charles Lower who discovered this HII region in 1939. It is also a member of the Stuart Sharpless catalogue where it is designated Sh2-261.

This emission nebula is located in the constellation, Orion and can be found North of Betelguese. It is approximately 2,900 light years distant, 26 light years across and has a visual magnitude of +10.

Being situated in Orion it is surprising that it was not discovered sooner but given the competition from M42 and the Flame and Horse Head nebulae, it is not unexpected that this remains an infrequently photographed object.

Data

HaRGB Composite with subframes made up as follows 36:12:12:12.

Exposure time 300s.

Darks x 50; flats x 25 and dark flats x 25.

Equipment

William Optics Z103 refractor

ZWO ASI1600mm Pro Cool camera.

ZWO EFW.

Chroma 1.25” filters.

SkyWatcher EQ6R-Pro mount.

Software

Sequence Generator Pro for data acquisition and equipment management.

PHD2 for guiding.

PixInsight for processing.

Thank you for dropping by.

John

16 hours ago, RobertI said:

lovely image John.

Thank you Rob. It was nice to be out under a clear sky for a change.

Happy New Year.

John

NGC2403

 Located in the Northern constellation Camelopardalis, this intermediate spiral galaxy is approximately 10 million light years distant and 50,000 light years across. It includes a large number of star forming Hii regions that glow pink/red as the gas is energised by hot massive stars. NGC2404 is such a star forming region as seen in the annotated image.

NGC2403 is thought to be part of the M81 group of galaxies but was not catalogued by Charles Messier despite it being located close to both M81 and M82.

The galaxy is not only active in star production but has also had its fair share of bright supernovae as massive stars come to the end of their lives. There have been two such occurrences, SN 1954J and SN 2004dj, the latter being the brightest supernova discovered this century on 31 July 2004 at visual magnitude 11.2.

Data

This image was captured on 4^th January 2022 in LRGB. 20:20:20:20 subs with an exposure time of 5 minutes. Total integration time 6.6 hours.

Calibrated using Flats x 25, Dark Flats x 25 and Darks x 50.

Equipment

William Optics Z103 refractor.

ZWO ASI1600mm Pro Cool camera.

ZWO EFW.

Chroma 1.25” filters.

SkyWatcher EQ6R-Pro mount.

Software

Sequence Generator Pro for data acquisition and equipment management.

PHD2 for guiding.

PixInsight for squeezing the life out of the data.

Thank you for dropping by.

John

Located in the constellation Camelopardalis, IC 342 is a large intermediate spiral galaxy some 10 million light years away. Given its size and distance IC 342 should be nearly 2 magnitudes brighter but for its location relative to our own.

Only discovered in 1892 by William Denning, it is thought it avoided detection for so long because it is positioned in dusty areas near the galactic equator of our own Milky Way which made it difficult to observe. Viewing through this cosmic dust gives it the reddish brown hue.

IC 342 is thought to be undergoing further star formation with Hii regions visible in the core and the spiral arms.

• William Optics Z103 refractor with 0.8 reducer/flattener.
• ZWO ASI1600mm pro cool camera.
• SkyWatcher EQ6R-Pro mount.
• Chroma 1.25” 3nm H⍺, Oiii & Sii filters.

• H⍺ - 113 x 300s.
• Oiii - 52 x 300s & 31 x 600s.
• Sii - 51 x 300s.
• Total integration time 23 hours.

As well has having my own imaging equipment at home, I also subscribe to iTelescope. This gives an outlet to scratch that imaging itch when the weather in the UK is poor, access to equipment I can only dream about as well as deep sky objects I will never capture with my own gear.

Whilst the Heart Nebula is visible from my location in North Essex, I was more interested in the heart of the Heart and Melotte 15. iTelescope have in Nerpio, Spain a 12” Planewave CDK Astrograph and so I attempted to give this a go to capture Ha, O3 and S2. I started at the beginning of October but like here in Essex, Nerpio was also suffering with poor weather but eventually I prevailed after rebooking my image runs several times, naturally to coincide with a near full Moon. Ah well.

So here is 6 hours in total (2 hours of each channel) of Mel 15.

iTelescope provide the sub-frames already calibrated with darks, flats and bias frames, however, this data needed a lot of help as the camera sensor had significant column defects which the calibration did not remove. The image below is 24 stacked Ha subs using the ImageIntegration process in PixInsight. The image looks blurry as the subs have not been star aligned. This is deliberate as the intention is to reveal the problems more clearly by stacking the defects (they already exist on the sensor in the same place in each sub) whereas if we ran the StarAlignment process first before ImageIntegration each defect would be in a slightly different position.

Fortunately, PixInsight has two great scripts for identifying and locating (LinearDefectDetection) as well as ‘removing' (LinearPatternSubtraction) these defects and a bit of CloneStamp finished the job.

Swapped the budgie smugglers and Ray Bans I wear for solar imaging and have donned the thermals and head torch for deep sky.

The old Cave Nebula presented here in red and grey depending on what floats your boat.

113 x 300 s using Chroma 1.25” Ha 3nm filter, ZWO ASI1600mm Pro Cooled, William Optics Z103 and an EQ6R-Pro mount then squeezed through the PixInsight sausage machine.

Bye for now,

Hughsie

Two consecutive clear nights (a rare event this year) in North Essex allowed me to swap the Lunt and sunglasses for a head torch and point my William Optics Z103 (Big Willie) up towards Cygnus and IC 5146.

A bit of research before hand revealed to me that capturing this nebula in the South East of the field of view would allow me to also reveal the dust lanes to the West which gives the impression (to me any way) of the Nebula rolling down into the corner of the frame.

12 minutes ago, peter shah said:

great work....love your star colour

Thank you Peter.

Friday 27th August offered up a clear sky and a change of pace. This year I have been spending more time solar imaging which was great as the night skies have been clouded out.

I needed to get back into the swing again and chose a simple target, Messier 39, which was conveniently located in Cygnus, near the Zenith and a reasonable distance from a rising Moon.

Data

• Red - 81 frames @ 60 s.
• Green - 79 frames @ 60s.
• Blue - 65 frames @ 60 s.

Equipment

• William Optics Z103 APO refractor.
• ZWO ASI1600mm Pro Cool.
• SkyWatcher EQ6R-Pro.
• RGB 1.25” Chroma filters.
• Data acquired using SGPro.
• Pummelled to death in PixInsight.

Our star today captured before the Bank Holiday clouds rolled in. Presented in RGB and monochrome.

• Lunt 60 mm DS TH⍺/B1200CPT telescope.
• ZWO ASI174mm camera and tilt adapter.
• SkyWatcher EQ6R-Pro mount.
• 3x Altair Astro Barlow and 4x TeleVue Powermate where stated.
• Images acquired with SharpCap Pro.

Images 1 & 2 - The Sun today. The full solar disc revealing some small prominences on the South East and Western limb, AR12859 in the Northern hemisphere and AR12860 in the Southern hemisphere.

Images 3 & 4 - AR12859 captured using the 3x Altair Astro Barlow. This region is located N22W28 and contains a single sun spot. Classified Hsx. AR12859 has been producing flares, the largest was classified C3.1 which occurred on 20th August 2021. 

Images 5 & 6 - AR12859 captured with the 4x Powermate.

Images 7 & 8 - AR12860. This is a massive active region comprising 24 sun spots and classified Eki. On Friday 27th August it was made up of 73 sun spots! This region is located S29W17 and has been producing flare activity, the largest being an M4.8 class flare on 28th August 2021. On Friday 27th August a C3 flares from this region launched a CME that is expected to reach Earth on Monday 30th August 2021. Captured using the 3x Altair Astro Barlow.

Images 9 & 10 - AR12860 captured using the 4x Powermate.

Images 11 & 12 - Prominences on the Western Limb (West is up) along with AR12859 (left) and AR12860 (right).

If photographing clouds and growing weeds were profitable I would be a millionaire by now!

Cloud dodging was the name of the game but I think my patience was rewarded. 

Images 1 & 2 - AR12859 located N20E25. Captured with a 4x Powermate and the equipment listed below. Comprised of a single spot and classified Hsx. Between 12:03 UT and 12:24 UT this region produced a small class B9.0 solar flare.

Images 3 & 4 - AR12860 located S27E36. Captured with a 4x Powermate. This region is comprised of 10 spots and classified Cao.

Images 5 & 6- A close up of AR12859 captured with a 4x Powermate. Presented in RGB and mono.

Images 7 & 8 - A close up of AR12860 captured with a 4x Powermate. Again, presented in RGB and mono.

Equipment;

• Lunt 60mm DS TH⍺/B1200CPT scope.
• ZWO ASI174mm camera and tilt adapter.
• SkyWatcher EQ6R-Pro mount.
• Images acquired using SharpCap Pro.
• Barlow/Powermate as listed.

300 out of 1,000 frames stacked.

Thanks for viewing.

Hi Damian, thank you for your comments.

The solar book is a great read. Some parts are highly technical, however, there is some really good ideas and tips within it. The processing section is brilliant plus there is a section on info available on the tinternet. Enjoy the read.

The large prominence we have been imaging on the North East limb these last few days has, due to the rotation of the Sun, moved on to the disc and is a now a filaprom. AR12858 is positioned towards the centre of the disc N12E03 made up of 6 small spots and classified Cro.

I had a brief window between clouds and was very lucky to catch the image below with a Lunt 60mm THa/B1200CPT double stacked, ZWO ASI 174mm with tilt adapter and a 3x Altair Astro Barlow. 200 from 1,000 frames stacked, inverted in ImPPG and finished in PixInsight.

Having set up my imaging gear yesterday morning I was waiting for the Sun to come into view and took a snap....

A few hours after I finished by solar observing yesterday, a few new active regions sprung up all conveniently located together and shown here.

On the 13th August I noticed I had a light leak in my image train creating light smears across the sensor. The Lunt telescope came with a a cloth bag which is pretty useless as bags go as you can’t place the scope in the bag and then into the carry case.

When I noticed the light leaking in I thought I needed something to cover it. My wife had the washing out and I thought about using a pair of my pants (underwear for any Americans reading this). But as I already had my head under a black sheet so I could view my laptop screen without glare, the last thing I needed was someone looking over the fence seeing a man under a sheet with his pants on his telescope which is pointing at the Sun.

Somehow, the Lunt bag seemed more appropriate.

Unfortunately, I forgot to use the bag today despite it being smack bang in front of me. 

Don’t ask if there were any pants to hand.....just look at the pictures and smears!

Image 1 - The solar disc revealing AR12855 / 57 & 53.

Images 2 & 3 - A closer view of the three active regions mentioned above both in mono and RGB.

Image 4 - A nice prominence on the South East limb.

Image 5 - A much larger prominence on the North East limb.

Hazy start to the morning with slow moving high cloud all over the place. Here is a selection of what was visible earlier today.

Image 1 - The full solar disc. AR12853 got its spots back and has been producing decent flares whilst AR12855 lost a spot but is still hanging in there. Oooh then there is those nice proms on the Eastern side of the solar disc.

Images 2 & 3 - AR12853 classified Axx and located N22W13 on the disc. At the time of imaging it had two spots. It has been producing A class flares but last night SDO detected an increase in strength to C1.5 at 21.05 UT. Here we have both a wide view of the region and a closer inverted version.

Images 4 - AR12855 classified Axx and located N13E32 on the solar disc. Yesterday it had three spots but one has since decayed. Ar12853 is lurking in the top right hand corner.

Images 5 & 6 - A prominence on the North East limb and estimate of its height plus a gentle reminder of how insignificant we are.

Images 7 & 8 - Another prominence this time on the South East limb.

All the best,

John