Use of Siril in astro landscape

Łukasz Żak is the best I've seen. Perhaps he can chime in for you.

Raphael Lencrerot:
I'm shooting astro landscape (not DSO). I was wondering if Siril could be beneficial

Yes, you can do the following:
- Shoot multiple exposures at the maximum shutter speed before seeing star trails. Usually it's the 500 rule: 500/focal ratio = number of seconds that you can shoot. However trial and error is best.
- Shoot some dark frames (same settings and shutter speed as the normal frames, but cover your lens with the lens cap and a blanket or something)
Then in SiriL:
- Import all dark frames and create your master dark: https://siril.org/tutorials/tuto-manual/#darks

- Start a new sequence and import the normal frames: https://siril.org/tutorials/tuto-manual/#converting-files
- Import all frames, convert them to FIT, then use the Calibration menu to calibrate them with your master dark.
- Register and Stack all the photos using SiriL and ignore the fact that the landscape will be completely black.
- Crop the image so only the sky is visible
- Go to Image Processing -> Background Extraction and use RBF to extract the background sky. This is done by clicking Generate, then making sure that none of the squares are on stars or on very light areas, then clicking on "Compute Background" and "Apply". To remove squares, use right click. To add squares, use left click.
- If needed, go to Image Processing -> Generalized Hyperbolic Stretch Transformations and stretch the histogram according to your taste.
- Alternatively, instead of GHST you can use Image Processing -> Histogram Transformation. This option is much easier to use and more in-line with traditional photo editing software, but it doesn't give you as much control as GHST.
- Save as TIFF

- In your favourite raw processor (I use CaptureOne), edit one of the photos - not the tiff, but one of the raw photos from your camera - until your are satisfied with how the foreground looks. Export this as TIFF.

- In your favourite photo editor (I use Affinity Photo), load both TIFF files as layers, align them and then combine them to your liking so that the final image will be composed of the single-shot foreground and the stacked sky.
Export this as TIFF

- Load the final TIFF into your raw processor - CaptureOne in my case - and do any final post-processing edits to the composite image.
Export, publish and have fun!

Example: https://www.astrobin.com/u175sw/  (no darks, just light frames)

Clear skies!

My lastest image in my gallery is a landscape edited in Siril: https://www.astrobin.com/h87ur3/

I find that Siril doesn't do a good job stacking with very short focal lengths (my case was a 14mm Rokinon). So I stacked in Sequator.

I cropped out the foreground on each image prior to stacking, I got better results than keeping the foreground in. Just be sure that your crop size is identical across all images.

Once stacked I went into Siril for PCC, SCNR and starnet. No background extraction (it looks too flat for landscapes)

Starless image stretching was done in Siril (arcsin, Histogram, and GHS)

Then saved the starlesss as a TIF to be brought over to Photoshop for final touches.

I then opened the TIF in Siril saved as a FIT and did star recomposition with the star mask (I like Star recomposition better than just doing a screen blend in Photoshop)

Saved the combined image as a TIF and brought back into photoshop to replace the sky on my foreground image. 

Alot of back and forth but I thought it worked out better than just editing in Photoshop.

It's by no means a professional image but I'm happy with it!

CS!

Ethan Sweet:
My lastest image in my gallery is a landscape edited in Siril: https://www.astrobin.com/h87ur3/

I find that Siril doesn't do a good job stacking with very short focal lengths (my case was a 14mm Rokinon). So I stacked in Sequator.

I cropped out the foreground on each image prior to stacking, I got better results than keeping the foreground in. Just be sure that your crop size is identical across all images.

Once stacked I went into Siril for PCC, SCNR and starnet. No background extraction (it looks too flat for landscapes)

Starless image stretching was done in Siril (arcsin, Histogram, and GHS)

Then saved the starlesss as a TIF to be brought over to Photoshop for final touches.

I then opened the TIF in Siril saved as a FIT and did star recomposition with the star mask (I like Star recomposition better than just doing a screen blend in Photoshop)

Saved the combined image as a TIF and brought back into photoshop to replace the sky on my foreground image. 

Alot of back and forth but I thought it worked out better than just editing in Photoshop.

It's by no means a professional image but I'm happy with it!

CS!

Interesting idea with extracting the stars prior to stretching on landscapes, it definitely allows to have a bit dimmer stars in the final composition. Nice.

Prueba este programa gratuito

https://sites.google.com/view/sequator/introduction

Thanks for your reply. I wasn't clear in my first post sorry for that.
I'm not really looking for a stacking tool. When doing astro landscape with a tracker, sometime you can afford to do stack sometime not, especially if you do MW arch for instance. I was wondering if I could enhance the image (post-processing part) with a tool such as Siril in astro landscape case. I'll put image example I did recently, processed with Lightroom and photoshop. I just wanted to know if I could do better with a tool such as Siril or PI. But PI cost is deterrent.