Winter triangle - a photo on Flickriver

Winter triangle

1 stack of 45 images, Canon 800D at ISO 800, Samyang 16mm f2 lens at f2.8, 1m exposures, Omegon Lx2 tracking mount. 45 darks, 120 biases. Processed in PixInsight as below

***** Integration
lightvortexastronomy tutorial (www.lightvortexastronomy.com/tutorial-pre-processing-cali...)

* CC defect list + master dark
* weighing: (15*(1-(FWHM-FWHMMin)/(FWHMMax-FWHMMin)) + 15*(1-(Eccentricity-EccentricityMin)/(EccentricityMax-EccentricityMin)) + 20*(SNRWeight-SNRWeightMin)/(SNRWeightMax-SNRWeightMin))+50
* img 1311 ref

*****Linear processing

*** Crop

*** Background extraction:
DBE tolerance 3, no points placed on the Milky Way

*** Color calibration
SNCR 0.5
Background neutralization
Color calibration

***Deconvolution
Created star mask for larger stars - large scale structure 2, small scale 1, noise threshold 0.1, scale 6,
Extracted luminance, STF autostretched, histoed peak in middle to get a range mask
Deconvolve with range mask on, 80 interations, custom PSF, dark 0.01 bright 0.004, local deringing with star mask, wavelet regularization

*** Star reduction (for small and mid stars)
Small star mask - noise 0.15, scale 4, small scale 3 comp 1, smoothness 8, binarize, midtones = 0.02
Range mask from that, 0.05-1
Apply, erosion operator 4 iterations 0.15

*** Linear noise reduction
jonrista.com/the-astrophotographers-guide/pixinsights/eff...

*TGV - small noise
Created TGV masks - extracted luminosity, standard stretch (tgv_luma_mask), curved it with black point at ~0.2 and white at ~0.5, moved histogram point to middle (tgv_mask)
apply tgv mask inverted to the image, give luma mask as local support
TGV chroma str 7 edge protection 2E-4 smoothness 2 iterations 500
TGV luma str 5 edge protection 1E-5 smoothness 2 iterations 500

*MMT - larger noise and TGV artifacts
Created MMT mask - extract luminosity, standard stretch, move histogram point to 75%, apply low range -0.5. Apply inverted
MMT mask - 8 layers, threshold 10 10 7 5 5 2.5 2 2 on rgb

***MLT stretch
www.stelleelettroniche.it/en/2014/09/astrophoto/m42-ngc19...

**Initial
* created a new multiscale linear transform, kept 4 layers using linear interpolation
* diffed from original image to create a "blurred" version of original image
* extracted luminance from original, used as mask on blurred version
* used curves to create s shape in luminance and saturation, inflection 3/4 up
* pixelmath sum the 3, rescaled, back to original image

**Second
* new multiscale linear transform, keep 5 layers
* diff from original
* extract luminance from blurred image, to use as a mask
* masked blurred image with its own luminance, gave it s-shaped RGB curve, slight boost in luminosity, big boost in saturation
* pixelmath sum the 3, rescaled, back to original image

**Third
* new multiscale linear transform, keep 8 layers
* diff from original
* extract luminance from blurred image, to use as a mask, hist stretch it (multi_8_substracted_L)
* luminosity increase (1 curve), saturation (even more)
* pixelmath sum the 3, rescaled, back to original image

*** Darken
* DarkStructureEnhancer, 8 layers, 0.7, 3x3
* DarkStructureEnhancer, 8 layers, 0.7, 5x5

*** Color saturation
* truncated star mask with pixelmath, iif(star_mask_total > 0.5, 0.4, 0)
* applied a troux wavelet transform 4 layers, extracted residuals
* applied mask inverted
* bumped reds strongly, green-blues less strong

*** Sharpen
* Sharpen with multiscale linear transform, bias layers 2-6 (0.05, 0.05, 0.025, 0.012, 0.006)

Taken on: January 31, 2020

Tags:

nightscape

astrophoto

orion

milky way

sirius

m42

barnard's loop

flame nebula

horsehead nebula

rosette nebula

m46

m47

Samyang 16mm f/2.0 ED AS UMC CS

Astrometrydotnet:id=nova3913530

Astrometrydotnet:status=solved « less

Sets appears in: • Astrophoto

Groups appears in: • Nightscapes - Natural Landscapes at Night • After Dark - Night Photography more » • Astronomy • the skies above • Slow Shutter Speed • Night Sky, The • Deep Space Astrophotography • The Milky Way • Amateur Astronomy • Nocturnes - Night Photography • astrometry • ASTROPHOTO • Manual Focus Lenses • Wide Field Astrophotography - Starry Skies • The Lights Of The Night Sky • BBC Sky at Night and Stargazing Live • Starry Night Astrophotography • Astrophotography (Pixinsight Processing) • Universe Today • The Stars at Night -- P1/C1 • Backyard Astrophotography • My First Astrophoto • Stars n' Stuff • Samyang 16mm/2.0 • Camera Lens Astrophotography • Amateur Astro-Photography • Beginning Astrophotos • Samyang Lenses - Official Tag Required • Genuine Milky Way Colors • Samyang & Rokinon Astrophotography • * Milky Way Photography ☆ • The Art of Astrophotography • Astro Imaging « less

Stats: 6,399 views / 4 comments

go back

Link to this photo view:
Link to this photo large view: