About
I started out with a Sky Watcher 130P telescope for observing the night sky over the years, and developed a passion for astrophotography in late 2021. Ever since I’ve been hooked. Living in bortle 6 light pollution area, I do my astrophotography with a Sky Watcher AZGTI mount in EQ mode with a Canon 1100D camera (astro modded) and using a Samyang 135mm lense. I use light pollution filters in the camera which are currently a Skytech CLS filter and a Altair Quadband Filter.
All of that is then connected to a ASIair Mini for control of the mount and camera from the comfort of my house using a computer for electronically assisted astrophotography.
Most of my deep sky images are between 2-3 hours exposures. I use mostly 30-60 second eposures and plan on adding a guide scope and camera to allow longer exposures in the future.
My goal is to share with you my photos, some of the techniques/tools I use and hopefully get you to look up at the sky a little more often.
Latest Image – Orion Nebula
Recent Posts
Photoshop Plug-ins to Make Astro Image Processing Easier
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✴︎ Posted on: November 20, 2024
When it comes to processing my images, i mainly use photoshop for processing my nights imaging data. With the help of plug-ins, they can make the process much easier. My main plug-in set come from a series of plug-ins from Russell Croman, these are very popular among Astrophotography enthusiasts.
GradientXTerminator
My first bought Croman plug-in is called GradientXTerminator. This is a must have plug-in as gradient is always a problem for astrophotographers, it’s job is correcting the gradients (uneven backgrounds).
Fixing this is quite simple. Open an image where uneven backgrounds are messing up your photo. Outline your image with the lasso tool. Invert the selection so you are selecting the sky, which is where the gradients are going to be.
Then, bring up the plug-in and choose how much strength you want the algorithms to use to repair the gradients. On top of that, GradientXTerminator will balance the color of your image.
NoiseXTerminator
Noise is also a big issue for astronomical images. Shooting in very low light and using long exposures, noise is always the result.
“NoiseXTerminator was trained exclusively on deep-sky astrophotos, so its neural network is familiar with how stars should look and the types of detail we see in our photos. It can perform natural detail enhancement without boosting noise or inventing non-existent structure.”
Here is an example of a before and after once you have run the plug-in on an image. There’s plenty of noise in it
After running NoiseXTerminator things are much cleaner.
StarXterminator
This plug-in is truly remarkable and i wouldn’t be without now. Here’s Croman’s explanation:
StarXTerminator uses an advanced convolutional neural network with a unique architecture suited to this task. This network has been extensively trained on photographs from a wide range of instruments, from camera lenses to the James Webb space telescope. Small stars, big stars, huge stars, and even diffraction spikes are recognized and removed, with minimal impact to non-stellar features.
This is a valuable tool to have. Nebula are stunning without the star background, but StarXterminator is really valuable because it lets you separate the stars and your main object on different layers, allowing you to adjust the stars to your liking while leaving the nebula or galaxy untouched.
Here is an example image of Orion Nebula with all the stars removed.
Generally i save the stars and put them on a separate layer so I can process both a star and starless layer independently, but these objects without stars are pretty compelling, although not accurate as to their real-world view.
Photoshop StarXTerminator process.
- Use StarXTerminator prior to any major processing of the image. The effectiveness and quality of the result from StarXTerminator will be adversely affected by any processing that significantly alters star profiles.
- To generate a separate starless and stars layer, follow this procedure:
- Start with the image you want to separate on a layer
- Duplicate this layer twice so you have three copies of the original image
- Remove the stars from the top-most layer using StarXTerminator
- Duplicate this starless layer so you have two copies of it
- Drag one of the starless layers down so it is between the two remaining original layers. Name this layer “Starless”
- Invert the top-most starless layer and set its blend mode to Divide
- Invert the next layer down (a copy of the original)
- Merge the top two layers into one. This will now be an inverted image of just the stars.
- Invert that merged layer. This is now the stars layer. Name it “Stars”
- Set the blend mode of this Stars layer to Screen
- The combination of the Stars and Starless layer below should look exactly like the original image
- You should end up with three layers in this order (top to bottom):
- Stars (screen blending mode)
- Starless
- Original (in case you need it)
- Process the Starless and Stars layers separately to taste
Summary
If you’re using Photoshop for processing, I think some or all of Croman’s tools are must-haves. They can save you a lot of time and give you better results than you will likely get just using Photoshop’s built-in tools.
Processing astronomy images is about as challenging as image processing can be. Roman has made a tremendous contribution to the art and the science of astrophotography.
His website is here, and you can check out each plug-in and purchase any of them if you desire.