Pixinsight Process

This time last year i tried a free one month trial period with the astronomy software pixinsight. It does appear daunting at first sight although as you start to use the software it becomes easier and familiar. I watched many tutorials on youtube but didn’t really find any that covered the whole process. I decided to create my own work process for the software combining different peoples methods on youtube. I hope it may be of interest to anyone starting out with the software.

Pixinsight Guidelines For Beginners

Process – Image integration

Add all bias frames, ignore format hints

Combination = average, Normalization = no normalization

Weights = don’t care, Scale estimator = meridian absolute deviation

Uncheck evaluate noise

Pixel rejection 1 = sigma clipping (no normalization)

Pixel rejection 2 = sigma low 3 sigma high 3

Execute and save master bias when complete (XISF or FITS)

Process – Image integration

Add all dark frames, Use the same settings as bias frames

Execute and save master dark when complete (XISF or FITS)

Process – Image calibration

Add all flat frames, ignore format hints

Specify output directory (create new folder for calibrated flat frames)

Output extension = .FIT   Postfix = _c

Select master bias (uncheck calibrate)

Select master dark (check calibrate plus optimize)

Uncheck master flat, Execute

Process – Image integration

Press reset parameters (bottom right)

Add all calibrated flats _c

Combination = average, Normalization = multiplicative

Weights = don’t care, Scale estimator = (ignore) Interactive k-sigma biweight mid

Uncheck evaluate noise

Pixel rejection 1 = Sigma clipping – Normalization = Equalize fluxes

Pixel rejection 2 = sigma low 3 sigma high 3

Execute and save master flat when complete (XISF or FITS)

Process – Image calibration

Add all light frames, Keep the same settings as before but add master flat (don’t hit calibrate under master flat)

Process – Image registration – Star alignment

Select reference image “file”

Add all calibrated light frames, Change output directory

Execute and save as _r  for registrar

Process – Image integration

Add registrar light frames _r          Hit reset settings for standard settings

Combination = average, Normalization = additive with scaling

Weight = noise evaluation, Evaluate noise checked

Pixel rejection 1 = sigma clipping (normalization = scale + zero offset)

Pixel rejection 2 = sigma low 3 sigma high 3

Execute and save as integrated light

Process – Geometry – Dynamic crop

Click image first, click reset, move box to cover image, execute

Process – Background modelization – Automatic background extraction

Target image correction = subtraction      Execute

Click on new preview mode and click on a dark area of the image creating a box (preview)

Process – Colour calibration – Colour calibration

Press reset, White reference – reference image = target image, Background reference = preview 1

Apply this and save as colour calibrated image

Press F12 and remove stretch

Process – Intensity transformation – Histogram transformation

Click real time preview, ensure 16 bit 64k

Middle slider to left and left slider slightly right trying to keep clipped pixels low, Apply and save as Histogram

Bottom left hand corner “zoom 1:1”

Click extract CIE L* component

Process – Intensity transformation – Invert

Click on tab and release on image, minimize mask keeping for later

(Remember white reveals, black conceals)

Click on icon “spying glass” to see image in real terms

Create new preview – encircle object (galaxy etc etc)

Process – Noise reduction – TGV denoise

Move edge protection until happy with details, Strength 5 ? Edge protection 3 ? Smoothness 2?

Click on image and apply, Save as TGV denoise

Remove mask

Process – Mask generation – Range selection

Preview, Click and drag, Lower limit – 0.240000 ? Smoothness – 75.5 ?

Close range selection , Apply mask to image

Preview – Process convolution – Unsharp mask

Open real time preview, click and drag middle slider until desired change

You can toggle on/off real time preview to see the difference

Apply to image and minimize mask

Process – Intensity transformation – Curves transformation

In “RGB/K” click two points of the curves line to tap down and move as desired

In “S” for colour transform move cursor to desired level and click apply

1 Response

  1. Thanks for sharing Ken. Makes me think I should stop being lazy with DSS and start pre-processing with Pixinsight.

    Also- been having some joy with the Dynamic Background Extractor instead of ABE lately. Think it depends a bit on the image.

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