Processing Stars using Photoshop and StarXTerminator

Are you getting frustrated by stars getting too bright and losing their colour when you apply your curve stretches to your Deep Sky astrophotography photos? Perhaps it is time to consider processing your stars separately. In this tutorial I show you how to remove your stars in Photoshop using StarXTerminator from RC-Astro, how to process your deep sky object without any stars at all, and then how to re-process your data to get an image of the stars alone. Finally I show you how to re-combine the two images (deep sky object and stars) to achieve a result that I hope you like.

[@hapestr]

Another comprehensible, pedagogical tutorial - thank you, Martin.

[@martinsastrophotography]

Thanks Hans Petter.

[@Photo-Stuff]

excellent teacher. I was looking for a tutorial on starxterminator, and learnt a lot about stretching while doing so!. You are very good to watch. Keep up the great work. A very well paced, relaxing and informative teaching style. Thank you!

[@martinsastrophotography]

Thank you so much!

[@andrepotgieter3722]

Thank you, Martin I really enjoyed this detailed tutorial.

[@martinsastrophotography]

Thanks Andre.

[@yangyunbo1]

thats the best video how to remove star halo i have seen ! it' s very clear and more logical!!thank you Martin

[@martinsastrophotography]

Thanks Charles. Appreciate the comment! Clear skies.

[@stevenrobinsonpictures]

Good video. Russell advises to remove the stars before stretching as you alter the stellar profiles too much. That's why you got the glow and improper removal of that star you had to clone out

[@martinsastrophotography]

Thank you. Yes, I have since seen that Russell recommended to do it before the stretch and I now mostly do that. Clear skies.

[@stevenrobinsonpictures]

@Martin’s Astrophotography yeh I found it out the hard way too!

[@crm114.]

Excellent tutorial, thanks.

[@martinsastrophotography]

Glad you enjoyed it!

[@michelleronald1794]

very clear steps and explanation...thanks!

[@martinsastrophotography]

Thanks Michelle. I appreciate your comments. Clear skies.

[@johnybaby2]

Thanks for sharing and nice shot. I am definitely going to try and capture the stars with rgb filters. I have been allocating sii to red and o3 to blue and green.

[@martinsastrophotography]

Thanks for your feedback. Enjoy experimenting….there is no right and wrong. If you like the result…happy days!

[@dumpydalekobservatory]

Nice tutorial Martin I've started doing something similar in Photoshop but I shoot using a one shot colour camera. I don't suppose you know a way of splitting the channels to make up a hubble palette using OSC?

[@martinsastrophotography]

Thanks! Hubble palette is a specific combination of Hydrogen alpha, Sulphur II and Oxygen III narrowband channels with SII in the red, Ha in the green and OIII in the blue. A one-shot colour camera shoots in Red/Green/Blue so what you are looking to do is not achievable without using narrowband filters. You can use a ‘duo-narrowband’ filter with a one shot colour camera, which will put Hydrogen alpha in the red channel and oxygen III in the blue channel, but this still doesn’t give you all three narrowband channels. You could then shoot more subs with an SII filter to complete the data set and then you could process the data using Hubble palette. I hope this helps.

[@suzannebeers6238]

I've used screen (vs lighten) for the star bending mode. Why do you use lighten? Have you found benefits to that over screen?

[@chrisfpv7615]

Very good video. I am new to editing and I was wandering if there is a way to keep the star halo's as wel without losing the real colours too? Thanks!

[@martinsastrophotography]

Thanks. Star halos are normally considered to be unwanted artefacts, so do you really want to keep them? I suspect not. They are often caused by the optical train including any filters used. Retaining real star colours requires first ensuring that your stars do not saturate. This can be achieved by using short enough exposures. However, short exposures are not good for deep sky object detail. It is therefore common practise to take both long and short exposures, allowing stars to saturate on the long exposures but not on the short ones. You then process the deep sky object using the long exposures, remove the stars, then create a true colour image of the stars using the short exposure shots and add these stars back in to produce the final image. This takes some practise but is very effective. It also helps prevent the stars from dominating your image too much.

[@ChemistryLectures-jv3sv]

Hi Martin. What version of Photoshop and Windows are you using. I tried installing StarXTerminator in CS6/ Windows 10. It doesn't show up in the filter menu. RC has no idea why!