Optimal workflow using SIRIL with COSMIC CLARITY SUITE PRO, GRAXPERT and AFFINITY PHOTO
I have
written a previous post about my SIRIL workflow which you can find here https://undersouthwestskies.blogspot.com/2025/01/a-beginners-guide-to-using-siril-some.html
In this post
I
· share my more simplified, reorganised
workflow - which is based on SIRIL vs 1.4, and the python scripts for Cosmic
Clarity Suite (by Seti Astro) and GraXpert.
· Try to give notes and tips which will
help beginners
· Share some useful, helpful YouTube
tutorials
So, let’s
get stuck straight in to my latest workflow: PLEASE NOTE - screenshots will be added when I process my next image - so please bear with me until then
NOTE: I am
assuming you have a little knowledge of how to organise your images – if you
are going to be using SIRIL – if you are new to SIRIL the jump down to the
bottom to watch one or two of the videos first.
A.
Organisation:
1.
Organise your folders into one folder called SIRIL and then sub folders for – lights, biases,
darks and flats
2.
Set your home directory top menu bar left hand side
3.
Choose scripts
– siril script files - OSC
pre-processing.ssf to start the stacking
process
B.
Crop and gradient removal:
1.
Be
in autostretch mode on bottom task bar
2.
Load
results.fits file produced from your stacking script – find in your home
directory
3.
Crop edges
to remove stacking artefacts
4.
Tools – astrometry - image plate solver on the pop up window:
a.
In
pop up window - search catalogue number; (S box = if southern hemisphere
image); click metadata from image; check – siril solver, solution order –
cubic, flip image, auto-crop for wide field, star catalogue auto, catalogue
limit – auto.
5.
Background extraction – image processing – python scripts - AutoBGe seti
a.
use default settings in the pop up window initially i.e. sample points 100, polynominal 2 RBF
smoothness – 0.1. (L-Enhance note - Use
degree 2 to avoid flattening extended Ha regions).
b.
On
the pop up window – can opt to click add exclusion area – (this is what you
don’t want extracted) – free hand draw in around nebula area to be excluded –
if make a mistake – click clear selection and start again – then when ready
click process
c.
Use
undo/redo arrows to compare before and after to see the changes
NOTES:
background extraction
1.
Can use GraXpert for BGE – GraXpert uses AI model - don’t
do denoise now just BGE – severe
gradients <0.5; mild gradients >0.5
6.
If using SIRIL BGE – grid
tolerance 3, squares off nebula and bright stars; click dither to on;
subtraction on; polynominal – increase for very bad gradients – RBF tab –
smoothing default 0.5
C.
Colour calibration:
1.
NOTE – must have done image plate solver before doing colour calibration
2.
Autostretch
mode on lower menu bar
3.
Remove chromatic aberration – python script - aberration remover –
can do now or after colour calibration – either
4.
Plate solve image – if not already done above MUST DO BEFORE COLOUR CALLIBRATION WORK - needs internet connection
5.
Colour calibration – image processing tab – colour calibration - Spectrophotometric
colour calibration
a.
SPCC – needs
internet – tick the
following: average spiral galaxy, one shot colour, osc sensor – closest, osc
filter – optolong L pro OR if narrow band – check narrow band box and enter
your filter details ( L enhance details for table – see below; tick background
reference to auto detection.
b.
Settings if using L-enHance filter - – wavelength : blue OIII – 500;
Green HB – 486; red H-alpha 656.3 and BW – OIII green 24; red 10; Blue 24
D.
Cosmic clarity sharpening before denoise
a.
DO BEFORE STRETCHING I.E. LINEAR
DATA
i.
stellar = stars only; non stellar = background and other objects - do both stellar and non stellar on
pop up window OR experiment using undo/redo arrows – use GPU, clear input
directory, (stellar sharpening - 0.5
default and play with slider; or move first slider to 0.20 to 0.25; non stellar
slider to 0.80; non stellar strength to 3. Zoom in a check – use undo and redo
buttons to see differences made
b.
OPTIONAL – could do DENOISE now – scripts – python scripts - CC denoise – use RGB channel;
check GPU and Clear input directory
c.
Now find output folder in Cosmic Clarity home folder and delete files as
you go.
E OPTIONAL stretching now – using Veralux
hypermetric Stretching NOTE – SEE F
BELOW BEFORE DECIDING
a.
MUST DO PLATE SOLVING AND SPCC COLOUR BEFORE HAND
b.
Linear view –
then Scripts – python scripts – processing – Veralux hypermetric stretching
c.
Settings
for pop-up window:
a.
Processing
– ready to use
b.
Sensor
calibration – top one or canon 600d or 709re recommended.
c.
Click
live view – use mouse scroll wheel to zoom in and out
d.
Target
background – start 0.10 (0.2 is default) (lower the number the more contrast
and darker the image – higher the number the less contrast and brighter the
image)
e.
Log
D – strength of stretch – leave at default 2.00
f.
Click
auto calculate
g.
Protect
B – how protected stars are during stretch – leave on default
h.
Star
core recovery – leave default 3.5
i.
Process
j.
Make
adjustments and experiment with setting inputs until happy
k.
If
over saturated use the slider – but RECOMMENDATION IS DON’T TOUCH THE SLIDER –
chromatic preservation colour one -
after alteration click auto calculate again
l.
Can
also now apply curves transformation if image looking too washed out etc – or
wait until starnet
d.
If
choose scientific – then after do series of transform curve stretches in siril
to bring up contrast and colour – s curves to raise darks, MT and HL’s
F.
Star removal: I always DO BEFORE STRETCHING
1.
Optional first step: Image processing – star processing desaturate stars
2.
Image processing – star processing - Starnet – tick prestretch in pop up window
3.
Stretching starless nebula – keep linear below in bottom menu
a.
OPTIONS: either
Veralux hypermetric stretch as above OR Cosmic Clarity statistical stretch –
see below
i.
Statistical stretch – in linear mode - target median 0.11 for anything not filling entire
frame; normalise- no curves adjustment; if fully fills frame target median at
0.25 starter.
ii.
Stretch
until: - Nebula structure is visible
Background is not clipped Stars
not blown out – NB if done colour correction already must check linked
stretch box.
Now the image is nonlinear and ready for detail work.
b.
NOTE
– CAN STILL DO OLD WAY IF DESIRE – SEE BELOW:
i.
OR – asinh
stretch first followed by HTF stretch – (HTF stretch using lhs and middle triangles
or placing points on curve line to get shallow s curve - watch clipping % - ensure no clipping of
data – ( can use ROI – draw box on part
of nebula – right click select |ROI – select ‘set to selection’ and do
adjustments; to remove – go back to menu and click ‘clear ROI’
ii.
OR Can also
retry with curves adjustment ticked – try boost slider at 0.5 – the
greater the boost the more contrast and fainter detail at expense of more noise
and artefacts -
iii.
OR can do curves transformation – tiny iterative changes and repeat image processing – stretches – curves
transformation – click on line and drag up or down – aim shallow s curve –
don’t clip data – make very small adjustments – repeat gently LESS is MORE
EXPERIMENT
WITH EACH UNTIL HAPPY – use undo/redo arrows
4.
Complete
denoise now – scripts – python scripts – processing – cosmic clarity denoise Denoise
a.
In
pop up windopw - full strength – do zoom in and undo/redo to check difference
b.
alternative is denoise in siril -
if using GRaXpert – default stretch 0.5 so try 0.8
(NOTE –
could try SETI ENHANCER if you have it
downloaded — Star Control, Detail Boost, Color Punch at this stage -
Load the denoised stretched image into SETI Enhancer.
·
Star Reduction
- Use after stretch, not before.
Strength: 10–30% Helps separate
the nebula from crowded star fields
Avoid “donut-shaped” stars—dial back if seen
·
Nebula Detail Enhancement Use: Local contrast Midtone sharpening Texture boost
Moderate levels keep it natural.
·
Color Enhancement
Increase nebula saturation Adjust
hue sliders for Ha/OIII separation
Use vibrance before saturation
Avoid boosting star colours too strongly
·
Background Balancing
Use background equalizer if available
Ensure background is smooth and neutral
Remove remaining gradients)
G.
Process starmask:
1.
Could Desaturate stars now – see above where outlined previously
2.
Can do Asinh
stretch or htf stretch – keep mild
– use square and eyedropper Asinh Stretch:
Broadband: 5–15 L-Enhance: 3–8 Black point: 0.001–0.003
3.
If doing GHS: Stretch:
0.8–1.2 Midtones: Broadband: 0.3–0.5 L-Enhance: 0.2–0.35
Stop here. Do not
adjust saturation, HDR, clarity, sharpening. OR
4.
Could Reduce star size now – image processing - morphological transformation –
selection – strength 5 – 20%
5.
Optional
Slight saturation boost - image
processing – colour saturation: do globally
H.
Star re-composition:
1.
Image processing – star processing – star re-composition
2.
On
pop up histograms - RHS is starmask; LHS is starless
3.
Do
black point adjustment to starmask to reduce number of stars
4.
Adjust
blend to avoid halos and bright stars – inspect fine details – zoom to check
edges
5.
Final
noise reduction – optional light GraXpert or cc denoise – avoid over-smoothing
background or killing faint dust
Final
tweaks:
1.
Vibrance,
colour balance
2.
Final
cropping/rotation to choice
3.
Green
noise check – SCNR (Green Noise Removal) – BEST = SIRIL Broadband: Strength: 0.60–0.75 L-Enhance:
Use none or mild (0.20–0.35) OIII contains green, so don't destroy it.
4.
Export
16 bit TIFF
PS Videos that I found useful:
