I have been imaging for the past 2 years and my processing techniques have slowing been getting better as you can be seen in my gallery progression (https://www.astrobin.com/users/Tackettbr/) . I use pixinsight predominantly with minimal photoshop. Recently, I have been taking longer exposures with my RASA8 F2 system and getting great SNR, but also picking up a lot of small high magnitude stars in my images. When I try different star reduction techniques (morphological transformation, EZ star reduction, and Adam Block Star deemphasis), These stars often turn into small gray circles that make the nebula and background look noisy and less sharp. See my example of the SHO tulip nebula (https://www.astrobin.com/44q8uf/). Screen capture below.
For my recent image of the lagoon and surrounding nebula in OSC and SHO (https://www.astrobin.com/4ywcop/, https://www.astrobin.com/ecyxtx/, screen capture below), I attempted a small star elimination technique that I devised. I used star net to removal the stars. I denoised the starless image using tgvdenoise to removal the small artifacts. Then I created a smooth range mask to remove the smallest tiny stars. I applied the range mask to the star image. Then with the larger stars masked, I used pixel math to zero the rest of image effectively removing the tiny stars. Then I added the new star layer back to the starless image. You can see the comparison before and after within the nebulosity on photo B of the OSC color version. See below with the right side before small star elimination and the left is the after results from the novel process.
I am looking for feedback or other processing techniques to help remove or dramatically decrease these small stars effect on the image. Most of the truly remarkable nebulae pictures I see have much smaller and fewer stars in the same size field that I am capturing.
Thanks in advance for any positive or negative feed back. Clear Skies! -Brandon
For my recent image of the lagoon and surrounding nebula in OSC and SHO (https://www.astrobin.com/4ywcop/, https://www.astrobin.com/ecyxtx/, screen capture below), I attempted a small star elimination technique that I devised. I used star net to removal the stars. I denoised the starless image using tgvdenoise to removal the small artifacts. Then I created a smooth range mask to remove the smallest tiny stars. I applied the range mask to the star image. Then with the larger stars masked, I used pixel math to zero the rest of image effectively removing the tiny stars. Then I added the new star layer back to the starless image. You can see the comparison before and after within the nebulosity on photo B of the OSC color version. See below with the right side before small star elimination and the left is the after results from the novel process.
I am looking for feedback or other processing techniques to help remove or dramatically decrease these small stars effect on the image. Most of the truly remarkable nebulae pictures I see have much smaller and fewer stars in the same size field that I am capturing.
Thanks in advance for any positive or negative feed back. Clear Skies! -Brandon
