I’m used to using the command line, because it allows doing more astro-centric stuff. But here’s a simple guide:
In the “File conversion” tab:
a. set the working directory to where your images are stored (“Change dir…” button")
b. click the " + Add" button to load the raw files
c. in the “Sequence name” field type “lights_”
d. click on “Convert” and monitor the output log until its done. EDIT: I forgot to mention that if you use raw files, make sure to check the “Debayer” check box.
Go the “Registration” tab" and just click on “Go register” (using the settings as in the screenshot below), and monitor the output log until it’s done.
Go to the “Stacking” tab and press “Start stacking” (using the settings as in the screenshot below), and monitor the output log until it’s done. The result is store in the “r_lights_stacked.fit” file.
Go to “File” > “Open” and open the “r_lights_stacked.fit” file. It should open 2 windows, one in RGB colors, and one with the 3 color channels in their own tab.
If you want to get and save a brighter image, go to “Image Processing” > “Histogram Transformation”, and click on the “Apply autostretch algorithm…” button, and press “Apply”.
To save the resulting image, go to “File” > “Save as”, choose the “TIFF” file format because you’ll need to further process the image later to correct colors in your favorite image editor (make sure to choose “16-bit unsigned integer” in the TIFF options.
Using the command line or scripts, you can benefit from quick/automatic preprocessing (removing green cast, perform RL deconvolution sharpening, detect and remove hot/cold pixels, crop…). That’s where an astro-centric program is really useful.
In fact, if you just want to align and stack images, even Hugin can do it quite well:
Load images and choose “Align_stack_images” to create the control points
Optimize for “Positions”
In the “Stitcher” tab check just “Combined stacks > Exposure fused stacks”
I’ve tried that and it works well on aligning stars and cleaning the noise with dark frames. But it leaves the foreground (if any) just as noisy.
2. Demosaicing the lights preprocess lights_ -debayer
Registering the stars (i.e., finding the stars in the files): register lights_
Stacking the registered lights: stack r_lights_ rej 3 3 -norm=addscale
Load the resulting stacked image in memory: load r_lights_stacked.fit
Optionally: postprocessing the image crop 30 30 5950 3970 (you have to change those numbers according to your files) log rmgreen 1 rl 10 0.6
It is also possible to autostretch the preview image, and with a right mouse click save as TIFF from the preview (I haven’t found a way to autostretch from command line).
Exporting the final image: save result.fit savetif result close
What I’m saying is that you can’t feed Siril with images of different sizes, or it will automatically resize them all by the smaller size (which seems to be fair). I mean, this is what I think it’s happening.
Why don’t you repeat the steps @sguyader draw with the raw files, this time checking the debayer option?
Hmmm, that’s strange. I was under the impression I was feeding full-sized tiffs.
I gave it another shot, feeding the raw files this time, the resizing issue is no longer present, but the output file is very very dark, way darker than the raw.
I was able to finish that, no automatic resizing from Siril.
This time (and the first, for me), I loaded the raws and simply selected Scripts → … No_flat_No_dark_No_bias script. It did all the job and produced a _result .fit image. While in Siril, it’s just a matter of file->save and select tif, so you can do the pp on a raw editor.
Here’s my take (basically, exposure to stretch the histogram, then filmic and tone curves)
15:07:39: Running command: cd
15:07:39: ‘lights’ No such file or directory
15:07:39: Error in line 18: ‘cd lights’.
15:07:39: Exiting batch processing.
15:07:39: Script execution failed.
I tried renaming the folder to lights, but no dice. What am I missing?
the script assumes you have the raws on a subfolder named lights. Do that and rerun it
But it won’t give anything much different from what you got manually.
I think it has to do with the fact that the debayer was done in linear space.
You have to pp the result in any raw editor and get back all the tones (they’re there, but hidden to our eyes)
EDIT: Also, I recommend you to take a look at the script output and note the script location. Mine is /usr/share/siril/scripts/ (yours is probably the same).
open a terminal (you’re in Linux, right?), cd to that directory, then issue a ls command. You’ll see all the scripts in there. Issue a cat DSLR_Preprocessing_NoFlat_NoDark_NoBias.ssf. You’ll see the steps it took to process the images.
No big deal.
EDIT 2: Regarding the result I got, I’m missing some color (aren’t there any red stars?). Maybe I did something wrong. Let’s see if @sguyader add some light here (pun intended).
Weird, now I have an issue.
I edit the resulting tif in darktable, then export it to jpeg, and the exported image is very different from the edited tif. The jpeg looses the big stars