MartinB

Thanks Paul. I managed to get an image of Neowise last year. That was a doddle compared with this speedy blighter!

Captured on night 25th to 26th Jan. Clear moonless night but bortle 5 sky Tak fsq106 reduced to 380mm f/l Asi 1600 mono cam Lum 187×30secs Rgb 24x30secs each channel All registered in PI and integrated for star layer. All aligned with the new PI comet align. The old version failed dismally Finished in PS

If you can do a sketch from memory of an observation that would be OK so long as you don't use aids such as photographs. You can submit as many entries as you like.

This challenge is now closed. The results will be announced within the next 2 weeks

Whilst this might be an opportunity for those handy with a brush or pencil it is also an opportunity for those who have never attempted an astronomical drawing/painting. The earliest astronomical drawings date back to the stone age. Astronomers started using early telescopes to create detailed pictures of the moon early in the 17th century. Sketching at the eyepiece is an excellent way to improve observing skills as well as providing a great record of an observing session. For the purposes of this challenge all sketches should be taken at the eyepiece as opposed to making a drawing from a photograph, there is no way of enforcing this other than trusting to your honesty and integrity! Using multiple sessions to create the sketch is fine. Drawings can use any medium - pencil, pastels, oils (!!) All astronomical objects are acceptable but please do not include any non sky foreground. Now hear is the important bit. The judging will be based not just on the presented picture but also the account of the creation of the sketch. So please give as much description as possible including prior sketching experience, telescopic equipment, the observing conditions, materials used and, particularly for novices, how you found the observing/sketching experience and what, if anything, you learnt. If you have any queries about the challenge please contact me via PM rather than from within this thread. Start date 1st February 2023 End date 30th April 2023 No entries will be accepted after this date. As previously the winner and runners up will receive an SGL challenge mug showing their image along with a virtual medal-of-honour for their SGL signature. Please post entries directly into this thread -- RULES All pictures should have been created by you, by you (no collaborative entries). Pictures must have been produced during the challenge start & end dates. Multiple entries are allowed but please make a fresh post within the thread.

Russ Croman, the creator of StarXterminator explains that his star removal is intended to allow stars to be processed separately to the rest of the image. This is invaluable because the characteristics of stars are quite different to nebulosity. How an image processor chooses to do this is up to them but the normal "rules" should apply, specifically, leave no jarring processing artefacts. I like stars to "sit comfortably" in an image, I know what I mean by this but struggle to explain it!

Thank you Olly for this carefully lobbed grenade 😁 Obviously the challenge was for star only images and software such as StarXterminator would have had no place. An interesting topic for discussion so I have started the ball rolling here https://stargazerslounge.com/topic/405192-what-to-do-about-stars/

So the SGL star challenge seems to have stimulated some thoughts about the treatment of stars in astroimages. So, is star suppression the work of the devil or can stars impair the visual impact of faint nebulosity. Are the latest star suppression tools being used to take things too far or are they a true blessing. Obviously there is no correct answer. Discuss, compare and contrast...

The results are in! https://stargazerslounge.com/topic/405115-sgl-challenge-10-stars/

I think this was quite a tough challenge, stars can be very beautiful but it is difficult to capture vibrancy of the view through a scope in a photographic image. We felt our winners did indeed rise to the challenge with 3 superb images. As usual there were other images which we could happily have included. I was a little surprised that no one submitted a Sirius animation showing the rapid changes of colour. That would have been difficult to compare alongside a static image so perhaps it was for the best! Many thanks to everyone who took part. 1) Fegato - Kemble's Cascade This beautiful binocular target and been superbly rendered in this two pane mosaic. 2) Alacant - HD34452 and friends Working with a humble Bresser 150 newtonian and a Canon eos 700d Alacant has captured a beautiful, immersive image. Star spikes can be a bit like marmite but here they are a feature of the scope and help to emphasise the scintillating dynamic quality of the stars. 3) Red Chilli - The Double Cluster It guess it was inevitable that everybody's favourite cluster pairing would make an appearance. There were some wonderful contributions. This image has managed to capture the intense brightness of some of the stars alongside the subtle colour variations.

Absolutely! I need to make it clearer that for the great majority of challenges drawings are very welcome.

I wonder if it would be possible to have Ez Reid test it. He does a lot of optical testing for @FLO He did wonderful job with my reducer when it had mould growing inside. Who did you buy it from?

Thanks @Rodd Sorry to hear about your scope issues. I don't understand the logic about small pixels and wonky stars. Did you get the scope new?

That's the thing about the HH. It looks great at 300mm and at 1000+mm, just different.

When I started this imaging mularky 17 years ago I managed a very blobby M31 using an 8bit Atik 2HS. From time to time I've revisited it and every time it's given me a headache but with improving results. This Autumn I decided to give it a once and for all final effort. At the same time I was trying to get to grips with NINA. This wasn't plain sailing and NINA is still work in progress, most of this data was captured with Maxim. Scope: Tak FSQ 106 with 0.73 reducer Camera: ZWO ASI 1600mm pro Filters: Baader LRGB L - 28x240s 183x300s RGB 14x300 each channel Combined using PI weighted batch preprocessing script then mainly PS

The bubble looks wonderful. The background is rather bright and has a magenta cast. For me this is detracting from the overall image. I had a go at tweaking the levels which is obviously a bit limited by using an 8 bit image but I think it shows the issue.

Well worth rejiging the pixels, beautiful image

Great work Rob and should definitely work nicely without the reducer. At least the horse isn't likely to gallop away.

Beautiful Steve. You should have entered this in the SGL Star Challenge

Fabulous! Superb framing and I like the colour. Overall it has a slightly smeared appearance possibly the result of some noise reduction?

It's looking good Lucas, especially the cropped version. Looking forward to seeing how it develops next year.

Hats off to you Wim, that is one faint fuzzy!! Very interesting

Ooh very nice. I love the faint touches of OIII

Terrific and nice to see the faint background details. I know stars are becoming "so last year" but I think they have the power to enhance as well as detract from an image. The stars here do have a slightly artificial attenuated look.

This is a lovely image. It looks dark and moody on account of the low black point. I had a look in PS and the average background value was 14. I think this is too low unless you are using it to cover up some background cosmetic issues. I think a background value of 25 would show a little more outer nebulosity and the image would appear a little bit less "constrained".