Starting with Siril

[8472]

Hi,

As a first time user, I'm trying to wrap my head around this stacking software. I'm using version 0.99.6, but the online english documentation is either out of date, non-existent or incomprehensible.

All I want to do is perform a mono Ha stack of Lights, Flats, Darkflats and Darks, but I can't even find out how to do simple task such as change the current working directory,(supposedly in the bottom right corner of Conversion tab), as instructed in an online guide (there's no button in this version!).

There also doesn't seem to be any provision for loading Darkflats from what I can see, either.

Can anyone point me to an easy to understand guide please, as none of it makes sense to me so far.

Many Thanks

 

[callump]

This tutorial is for an older version of Siril - but I think many of the basics are the same.  

https://pixls.us/articles/processing-a-nightscape-in-siril/

I'm not sure any of the scripts are currently set up to do dark flats - you cold do those manually though if you do the whole process manually, or you could adapt a script. I'm not sure of the efficacy of dark flats.

In the latest version the change working directory is the "Home" button at top left (next to Open).

I'm not an expert on Siril but if you have any questions happy to try and help.

Callum

 

[JonCarleton]

Actually, Siril is fairly straight-forward.  You start at the left tab (File Conversion) and work your way to the right one tab at a time.  You can use scripts, but you don't have to.

My process goes like this (very basic example):

File Conversion Tab:

1.  Change Directory to target directory

2.  Add files

3.  Assign a Sequence Name (eg: M31) and click Convert

Note:  Two Screens pop up with Red/Green/Blue segments of a FITS image and a composite RGB image.  The default setting for the main screen is Linear, but I like to change it to Auto-Stretch....not required, however.

Sequence Tab:

Here you can look at the images and exclude any as necessary.  You must pick a reference image (default= image 001.  You can click normalize here, but it isn't required.

1.  Assign a Base Name (eg: M31)

2.  Click Export Sequence

Pre-Processing Tab:

This is where you add darks, flats and bias images, if you have them.  It is not specifically required and makes pretty good sense, so I'll pass on the explanation of it for now.  First time, don't bother.  Once you are comfortable with the rest, use it!

Registration:

This is where your images are "looked at" by the software and judged.  It is a critical step.

1. Choose a registration method.  If a planetary image, pick either Image Planetary Alignment, if you just want to align the planet, or Enhanced Correlation if you have something like close-up moon shots and you want to align surface features.  If it is deep space, Global Star Alignment is your GOTO.  One Star align is a weaker option and should only be used as a last resort.  Obviously, comet/asteroid is for comets and asteroids.

2. Select Register All Images in Sequence ONLY if you have not made Exclusions in the Sequence Tab.  Otherwise, click Register selected images only.

3.  You may choose to click Simplified Drizzle or not.  It makes a difference on some types of image and not so much on others.

4.  Click Go Register.

I have never used Manual Registration, as the automation has always worked well for me IF the image quality is not terrible.  I suppose you could resurrect some data from bad images with the process, but I prefer not to bother.

Plot:

This shows the result of Registration.  If it looks like the patient is having a seizure, then perhaps it may be an indication you need to be more aggressive in the Sequence Tab with exclusions.

Stacking:

There are a variety of types and styles of stacking and rejection judging methods.  To keep this simple, one of the most popular for me is as follows:

1. Select "Average Stacking with rejection"

2. For Rejection method, try Winsorized Sigma Clipping (Read the docs for the differences...but this is a good start).

3. Below Rejection, change the dropdown from "all" to FWHM.  This basically will reject on quality (from the Registration step).  The default is to keep 90% of the best images.  You can play with that number as you choose.

4.  Next, and last is "Start Stacking"  

When it is finished, the stacked image will show in the two image windows (a few moments after completion).

 

 

Edited January 10, 2021 by JonCarleton

[Nerf_Caching]

Search up a guy called "Nebula Photos" on Youtube. He shows you how to use siril to stack photos. I learned to use Siril using his resources.

[8472]

Out of interest, I found a front end for this program called Siril IC.

It has made things so much easier to the point that I think I'll now use Siril as my go-to stacking and preprocessing option.

It does 90% of what the others I've used do but costs nothing.

[bottletopburly]

 Siri Scripts are easy enough to use but as a program I find it unintuitive and not user friendly manually, though gives good results   ,I tried Astap stacking the other day and found that the easiest stacking program I have used to date   after tweaking settings for processing in Startools  and they were minor tweaks .

Edited January 14, 2021 by bottletopburly

[8472]

Interesting.

I've not used ASTAP for anything other than platesolving in APT, tbh. Might be worth a look.

The must haves for me are stacking dissimilar image scales, effective gradient reduction/background extraction and the ability to preprocess and edit mono data. The two different paid software options I've been using up to this point do, and indeed Siril+SirilIC does too.

[OzarkSkies]

Has anyone seen a LRGB (Ha) script? I tried to use the Mono-preprocessing but, when it got to the lights folder it must not have liked what it saw and terminated the script. I had luminance, red, green and blue folders. Obviously it was looking for something else. Not sure that I have the skill set to write a script myself.

Edited February 8, 2021 by OzarkSkies

[alacant]

21 hours ago, OzarkSkies said:

write a script myself.

Hi

I'd strongly recommend you start by using the program manually. Go through e.g. stacking something simple like a bias or dark sequence. The app is self documenting. Hover over any item for an explanation.

Once you've done the basics a few times, it's then easy to understand what went wrong with the script. In fact, unless you've thousands of frames to process, it's just as quick manually anyway. 

HTH

Edited February 9, 2021 by alacant

[8472]

20 hours ago, OzarkSkies said:

Has anyone seen a LRGB (Ha) script? I tried to use the Mono-preprocessing but, when it got to the lights folder it must not have liked what it saw and terminated the script. I had luminance, red, green and blue folders. Obviously it was looking for something else. Not sure that I have the skill set to write a script myself.

Take a look at SIRILIC

It automates a whole slew of Siril tasks.