Hughsie

Hi, I am not sure what your circumstances are such as working full time, retired or somewhere in between. For what it is worth I have just completed the Open University course S177 Galaxies, Stars and Planets. It is a module, cost c£500 and ran from April to September. It needed c8 hours per week study time. The reason I took the course was to get a grounding of the science behind what I was observing. There is a little bit of maths involved and some use of Aladin - imaging software. Overall I found it fun and gave me a better appreciation of what I am observing. There is an end of module assessment which I have just completed involving short essays, math calculations and observational work. The course is run on a distance learning basis with as much or less contact with the tutors as you need. There is a text book to work through which is also accessible online via iPad etc. John

Having fun with narrowband too. Great image Knobby.

Please see attached a close up of an image in the SHO palette. If you examine the larger stars you will see two points of lights positioned at the 2 o’ clock and 8 o’ clock orientations and this is consistent for each large star. Although the image is a combination of Sii, Ha and Oiii, these artefacts only appear in the images produced using the Ha filter (Baader 7nm 1.25” filter). At first I thought it was hot pixels but then this would be a random distribution across the image whereas these appear to be associated with larger stars in a specific orientation suggesting a ‘mechanical’ issue. The image is taken using a William Optics Z103ED refractor with a Flat 6AII reducer attached using a ZWO ASI1600mm Pro Cooled camera. I have done some research online and can’t seem to find any mention of this type of artefact and was wondering if anyone else has experienced this before? Thank you in advance, John

Image from last night. Ha 20 x 300s Oiii 20 x 300s Sii 20 x 300s just stacked in PixInsight and a splash of colour added. Further work needed. John

Lovely picture Francis especially as the Moon wasn’t too far to your East. John

As Laurin mentions, click on the brain icon and select the ‘Algorithms’ tab. Look at the bottom right hand button under Dec. You may have “Dec Guide Mode” switched to off in which case turn it on. Then take some dark frames, calibrate and run the guiding assistant from the tools menu for at least two minutes and apply any suggestions it makes. J

I have this joy to come when another clear night occurs. I recently purchased this https://www.astroshop.eu/extension-tubes/astoptics-extension-tube-variable-m48-extender-23-29mm/p,57790 to help make the adjustments to back focus. It's attached to the field flattener at one end and a couple of spacers at the other and wound and locked to give 55mm spacing. I hope, let me say that again, I hope that with this in the image train I can then calculate the exact spacing needed to put in permanently. I hope. John

Mac user here but bit the bullet and purchased a recon windows laptop. However, this may provide a starting point for your research as to what is and isn't in the realms of possibility. https://www.macobservatory.com/mac-astronomy-software Cheers John

Hi Francis, I am no expert here but I follow the processing of calibration images which is posted on the Light Vortex website. https://www.lightvortexastronomy.com/tutorial-pre-processing-calibrating-and-stacking-images-in-pixinsight.html#Section2 .Just scan read Warren's book on calibration frames and there are subtle differences between his workflow and that described on Light Vortex. During my brief spell astro imaging I have used the ASI294MC and always taken dark flats opposed to bias frames and followed the Light Vortex workflow with no major issues. Might be worth a look. John

Stars nice and tight, great contrast and subtle colours. Looks lovely. J

Microsoft. The only Windows you can’t look through because they are covered in Microsoft clag. J

Thank you Adam. I have ready many of your responses on here and welcome your feedback. You are correct, I have been struggling to get the back focus correct and this was as close as I have got so far. I have been playing with the Flat 6AII on the WO Z103 and got the spacing right at 4.6mm but there are still some stars which are elongated as you have identified. I now have an adjustable spacer and (hopefully) it will allow me to establish the correct B/F and then put the right permanent parts in place to correct this. But a question for you. With the filters in play do I need to account for the thickness of the filter glass too? I understand this to be 0.7mm on Baader NB filters. Thank you in advance, John

Just ordered a small part from the guys and girls at Astroshop.eu. Arrived promptly and came with a small packet of Haribo Flo, I have to ask, I get Haribo's from our Euro friends and polystyrene and clouds from you! Only kidding, Flo and Astroshop.eu are top merchants and come highly recommended by me. Jelly Beans Flo? John

That will be the cling film kicking in!

I would have to be careful of the wife first!

If you get the weather Sean I say go for it. I use APT and saved the ra/dec settings of my second night but looking at my third night I may be a bit off target. Having said that I looked in Astrobin and saw an imager who had...... wait for it ..... SEVENTY FIVE HOURS of data. Well, you know what I say to that sort of commitment? I don’t wear thermals in winter, that’s what I say 😝 John

I used the Baader Ha 7nm and Oiii 8.5nm purchased from our good friends at FLO. Personally, I would like to see a softer image and try as I may I couldn’t remove most of the small stars. Spent 6 hours this morning post integration processing and just had to stop. I will come back to it in a few days as I have it saved as a PixInsight project so I can choose where I want to start from. john

Went a bit mad over the Bank Holiday Weekend imaging this target. Spent three nights overall on it. I have posted the first nights work already but was not happy with the framing as I knew there was more to see below the broomstick. The second night, 24 and 25 August, I felt was better framed. However, I went a bit mad as this was only my second narrow band session and was I playing with the filter wheel like a loon! I was trying them all Ha, Oiii and Sii, I even popped a few IR/UV subs in for good measure. You know if I could have wrapped cling film around it I would have shot that too....and probably got a better image. Anyway, with complete disregard as to what the target needed to best show it I realised later (not even on the third night when I was trying sandpaper and cardboard in the filter wheel), that NGC 6960 looks great as an HOO image. Fortunately I had some subs; Ha 16 x 300s gain 139 Oiii 20 x 300s gain 139 Both captured with the ZWO ASI1600mm Pro Cooled at -15c and a William Optics Z103 mounted on a HEQ6R Pro. Enjoy and any feedback welcome. John

Great effort with some good helpful feedback as well. John

Thank you Martin. I just noticed the red pixels in the Ha image. In the end I found an article on the PixInsight forum for red and blue 'blips' and followed the PixelMath workflow suggested to remove them. I had to boost the formula to stop it attacking the Hydrogen gas but it seemed to work...I think. It was bit of 'oh they are gone' then the 'but how....?' then 'don't knock it you've been scratching your head trying to figure it how for far too long!'. Thank you again for your kind comments and suggestion. John

The Western Veil also known as The Witches Broomstick and Finger of God is part of a larger structure representing a star which went supernova c8,000 years ago. NGC 6960 is part of the supernova remnant, the remaining parts being the Eastern Veil, NGC 6992 and Pickerings Triangle. Located in the constellation of Cygnus, this represents for me one of my favourite objects you can image in the night sky (well visible from my garden anyway!). I have previously imaged NGC 7000 in H-alpha and that was a prelude to going deeper on NGC 6960 using the HOO palette. The red channel is represented by H-alpha and the Blue and Green channels by Oiii. This being my first foray into narrowband palettes, it presented a number of challenges some of which I have not really overcome. First there was a large number of pinpoint red stars which had to be removed. Second, NGC 6960 sits firmly in the glow of the Milky Way and so to really appreciate the object it was also necessary to remove/reduce a large number of stars (with some artefacts visible). Finally, it was a question of getting the colour balance where I wanted it. I favour more subtle hues and hopefully this is reflected here. The imaging was undertaken on the night of the 23/24 August 2019 commencing at 21:51.The Hydrogen/Red channel was made up of 19 sub frames @ 240s; the Oxygen/Green & Blue channels were made up of 20 subframes at 240s. Overall 2 hours and 36 minutes of exposure time. I also took a similar number of Sulphur and Luminance images but have not used them here. I followed up again across the nights of 24/25 and 25/26 August with what I hope is a much better framed version of this target and hope to follow up with this second version in the coming days. Thank you for looking in. John

Paid user here too. The only issue I had with APT was connecting to the planetarium software, Stellarium. To be honest though I think that was rather a Stellarium/me issue than APT so in the end I chose to use Cartes du Ciel and have never looked back. If I recall correctly, Ivo actually extended an extra month free on the licence earlier this year......it was cloudy so never got used I have played around with the idea of using Sequence Generator Pro, but once you get used to APT, changing is very hard when everything works........and once you do your first plate solve, you will chuck away that finderscope and wonder what the hell you have been doing on your hands and knees star aligning every time you go outside at night. John

If you want to stay mobile and have a Vixen Polarie equivalent then you could look at the iOptron Skyguider Pro. It comes complete with the full kit needed to mount a Z61, which is what I use on mine. Costs cGBP415 or USD510 by my calculations. Like you I purchased the Polarie then hit the weight limit and baulked at the upgrade cost so sold it and bought the Skyguider Pro. The Skywatcher version is also an option but again you have to purchase the tracking unit and weight upgrade separately. Have a look at the weblink below and the associated YouTube video. Peter does a great job simply explaining the pros and cons of each having used both in the field. He also has some great set up tutorials on YouTube. https://www.peterzelinka.com/blog/2018/8/which-star-tracker-should-i-get Hope that helps, John

Narrowband would be an option on imaging, no worrying about the Moon or street lights. Astrodons if you have downsized and released a ton of cash or Baader/Astronomik for us mere mortals.