AMcD

This data was a joy to work on, compared to what I am able to extract from my Bortle 5 location. The entry was processed entirely in PixInsight, using the narrowband colour mapping script to combine the Ha, OIII and SII channels. I used the following workflow to produce the image: PIXINSIGHT Linear: - Star Alignment of Ha, OIII and SII channels; - Dynamic Crop to remove any stacking artefacts; - Dynamic Background Extraction for each channel; - Calculate PSF for each channel; - Apply BlurXterminator to each channel using calculated PSFs; - Combine channels by assigning colour values at full saturation to each channel (Ha: 353; SII: 25; OIII: 195) and applying Background Neutralisation in NBColourMapper; - Apply StarXterminator to combined image to produce starless image and stars image; - Apply NoiseXterminator to starless image; - Stretch starless image and stars image using Generalised Hyperbolic Stretch; Non-Linear: - Adjust contrast with Curves; - Adjust Colour Saturation; - Local Histogram Equalisation to bring out large and small structures; - Bring out further detail and highlights using range, luminance and colour masks; - Add back stars using PixelMath; - Apply star reduction script; - Adjust black point using Histogram Transformation. 😃

The weather is so epically bad, I have taken to looking at interesting features in my existing images. This is a very close crop of an image of IC1848 showing the Young Stellar Object Candidate 2MASS J02533920+6030174, to which I applied further processing, including BlurXterminator. The region in which the object is located is considered in a 2011 paper in The Astrophysical Journal (see Koenig_2011_ApJ_726_18.pdf), a paper looking at young intermediate-mass stars in the area covered by my original image: The original image (with 2MASS J02533920+6030174 arrowed) covered a much wider field, relatively speaking:

It appears to be widely accepted that an East heavy bias on the RA axis can assist with guiding, by addressing any RA backlash. Equally, following a meridian flip, there is a need to adjust the weight on the counterweight bar in order to maintain the bias. This latter requirement presents an issue for me, as I control my observatory remotely due to working away. This led me to consider the 'RA String Trick' whereby a weight on a string is used to apply a constant bias to the RA axis, allowing the RA axis to be East heavy both before and after the meridian flip without the need for manual adjustment. Using my less than refined engineering "skills" I built the following system. I began by fashioning a bracket to enable me to attach a pulley system to the mount so the necessary counterweights could hang free of the pier: I then sourced some bearings, pully wheels, axel and fasteners to mount on the bracket in order to hold the pulley wheels that would support the counterweight string: I then countersunk screw holes into the mount in order to attach the bracket to the mount. One advantage of having an elderly, second hand mount is that it is less nerve wracking to drill holes into: The mount was then reassembled (taking the opportunity to clean and re-lubricate all of the bearings): Once the mount was assembled, the counterweight string was attached to RA axis, looped twice around the RA axis: Finally, the counterweights were attached to the string. The counterweights come from an old set of weights that I bought in a fit of enthusiasm as a much younger man and the mounting for the weights was sourced from the fitness section of Amazon: Having balanced the mount, I then tested the system to make sure the mount could cope with the weight, first with 5lbs and then with 4.25lbs. The High Torque motors I fitted to the mount last year cope very well with the 5lbs of additional weight on the RA axis. The RA clutch, however, struggled with the 5lbs and was happier with the 4.25lbs, which was still enough to apply the necessary East heavy bias. Whether this system will make any appreciable difference to my guiding remains to be seen. I suspect, given the multiple variables that can impact on guiding, it will be quite difficult to definitely ascribe any improvement to this counterweight system alone, or at all. All that said, it has been fun to build and I am looking forward to testing it whenever these seemingly eternal clouds clear...

Yes, I think you might be right. It looked good on my iPad but in need of adjustment on my work laptop!

Many thanks, @ONIKKINEN. Patience is indeed the defining virtue of this hobby. By the end of this project I will be a Zen master😂

Thanks @WolfieGlos. These comments renew my determination to finish it, although I think given the time it takes to gather nine panels for each channel it may need next Autumn/Winter to finish gathering the data!

Thanks for your kind words @cfinn. The star halos have been one of the challenges. I did use BlurX to try to address them but much of the data suffered from intermittent high cloud. I think suspect this adds to the challenge of eradicating the halos. One consequence of the appalling weather conditions at present means I will have plenty of time to keep playing with the data, so I will keep at it!

Many thanks for the encouragement @tomato. Doing this in the UK certainly adds to the challenge. I have a feeling this will be a multi-season project!

I wanted this season to see if I could achieve an LHaRGB mosaic. On reflection, starting with a nine panel project on M31 was probably overly ambitious. The project has been a constant battle since August against the weather, with virtually no nights without poor seeing and/or some high cloud, a persistently misbehaving mount and, ultimately, pretty poor data for all panels of only the first of five channels. Processing in PixInsight required some brute force. All that said, as a learning experience it has been invaluable, if highly frustrating. Each panel is approximately 4.5 hours of integrations captured with my QHY268M and Antlia Pro Lum filter on my TS130 Photoline APO mounted on a Losmandy G11. Data acquired using SGPro. Constructive critiques most welcome.

Apologies if this has already been covered, but is there any maths (or, as my American wife would say, math) to consider in optimising the telescope / OAG / guide camera combination? I am planning to move to QHY OAG-M, which has an 8mm x 8mm prism, on my TS Optics Photoline 130, which has a focal length of 910mm. I am considering the ASI174MM or QHY5III678M as the guide camera, but wonder if there are any calculations I should be doing before hand to make sure it is the optimum camera to use?

Lovely depth and detail Lee. 👏

That is a stunning image Peter. The dust over the nebulosity gives it such a three dimensional feel.

That is a very good idea. I will drop him a line.

I think that asking city center dwellers to carry torches in place of streetlamps might carry certain risks come election time 😂

What has really struck me is just how much the new light fitting reduced the amount of stray light. Our back garden and our neighbours' back gardens form a closed square, the whole of which was bathed in orange light from this single streetlamp, much like in @OK Apricot's photo. The new fitting has eliminated all of this. In the circumstances, I can understand why an increase in the use of such fittings would contribute appreciably to the reduction in light pollution per the map. We too have seen the streetlights turned down in our area in addition.

About three years ago I asked our local councillor whether it would be possible to modernise an old sodium streetlight on a path at the back of our house, which shines directly onto my observatory and my neighbours' gardens. I explained the concept of light pollution and the adverse effect it has on amateur astronomy and astrophotography. He said he would see what he could do, and I heard no more. I have just noticed that the light has now been fitted with a new, shielded fitting that virtually eliminates stray light whilst maintaining proper illumination of the path. My observatory is now devoid of orange glow. It took a while, but it was worth asking. 🙂

I started off with Baader 2" LRGB filters but switched to Antlia Pro V LRGB 2" filters, which I am much happier with. The stars are much easier to control in processing with the Antlias. I also have the 3nm Ha and OIII from Antlia and am likewise very pleased with them.

I set up my observatory for remote operation a couple of years ago, albeit in the back garden rather than abroad! I documented the project in the SGL posts a below. The observatory can now be operated from anywhere in the world, which is particularly useful when I am away on work. Whilst I did the installation myself, the wiring diagram, the parts and a great deal of valuable advice was provided by Rupert at Astrograph (www.astrograph.net). He does a lot of telescope hosting in Spain and Chile and really knows his stuff and would be a good place to start.

Peerless!

Thanks Peter. I am particularly pleased with having resolved quite well the Young Stellar Object Candidate (2MASS J02533920+6030174) at the upper middle of the image (cropped version below), which is mentioned in a 2011 paper in The Astrophysical Journal (Koenig_2011_ApJ_726_18.pdf) looking at young intermediate-mass stars in the area roughly covered by my original image.

This is a further version of the centre of IC1848, this time in LRGB with the L and R channels enhanced with Ha and the G and B channels enhanced with OIII. The total integration time of 15 hours and 40 minutes comprises comprises 4 hours of Ha and 5 hours of Luminance, taken last Autumn, and 3 hours 40 mins of OIII and an hour each of R, G and B, taken over the past two weeks. The data was acquired using a QHY268M, with Antlia 3nm Ha and OIII filters and Antlia LRGB V Pro filters, on my TS Optics Photoline 130 APO mounted on a Losmandy G11 under Bortle 5 skies. The acquisition software used was SGPro and the data was processed in PixInsight. As always, constructive criticism welcome.🙂

The resolution on the 'Pillars of Creation' is incredible. As the proud owner of an increasingly ancient G11, I am glad the old mounts get the odd outing!

Great image. The blues in particular are wonderful. I think my equipment would like Spain 🙂

Many thanks for your generous words Peter. I used to get slightly vexed that the field of view of my TS 130 does not encompass the totality of the larger DSOs, but I am now quite enjoying picking out details in them (until I am brave enough to have a go at mosaics!).

This is my first attempt at combining narrowband data, in this case H-Alpha and OIII to produce an HOO image, with Luminance data also added, weighted at 60%. The data was gathered using a QHY268M, with Antlia 3nm Ha and OIII filters and an Antlia Luminance filter, on my TS Optics Photoline 130 APO mounted on a Losmandy G11 under Bortle 5 skies. The total integration time of 12 hours and 40 minutes comprises 4 hours of Ha and 5 hours of Luminance, taken last Autumn, and 3 hours 40 mins of OIII, taken during a rare clear evening last week. The data was gathered with SGPro and processed in PixInsight. I am hoping to gather some RGB data to replace the current Ha/OIII stars. Constructive criticism always welcome 🙂