Wipe module leaves bands at edges

Questions and answers about processing in StarTools and how to accomplish certain tasks.
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mikey2000
Posts: 9
Joined: Tue Nov 08, 2016 10:04 am

Wipe module leaves bands at edges

Post by mikey2000 »

Hi,

I'm still loving startools! But I have a persistent problem that I get when using the wipe module. - I often get a nice 'centre' of the wiped image but it's often just a rectangle at the center of the image. Sometimes I get broad bands along two or three edges. Not usually a problem as I can crop it a way

My workflow goes:
I shoot raw with a Sony A6000 camera and 150PDS at the edge of a small town (moderate light pollution)
DSS Average stacking with darks, flats and bias. Debayering options: Bilinear Interpolation (default) Set Black point to 0 = Yes. WB boxed left unchecked. I set 'no background calibration' in DSS (despite DSS keeps pestering me to switch it on.)
Load the AutoSave.fts into startools
Choose the first option when loading (from the choice of 4, linear blah blah etc)
Bin to 50% (to speed things up and it's still a 6mp file)
Autodev. Set 'ignore fine detail' to 1.1 (one mouse click)
Wipe and show temporary autodev. I find setting Dark Anomaly Filter to 10 or more works best.

This is where I see the bands at the edges. I tried comparing to a basic stretch in DSS. DSS doesn't appear to show the bands but maybe they are too subtle.

I'm a bit lost on how to cleanly wipe the whole image instead of the center only.

Here's an example:
DSS - basic stretch
https://1drv.ms/i/s!AvgOChdTHut6hNkO-k8fzvzNM1Ui-g

Startools after above steps:
https://1drv.ms/i/s!AvgOChdTHut6hNkP5W4do8HciRRphg

Any advice would be much appreciated.

I can also provide the original autosave.fts if you like but it's a big download!
almcl
Posts: 178
Joined: Wed Jan 21, 2015 7:15 pm
Location: Shropshire. UK

Re: Wipe module leaves bands at edges

Post by almcl »

I used to have this problem when I started using ST.

It resolved once I started cropping more aggressively before using wipe. Think its down to stacking artefacts that may not be apparent on the first Autodev.

Try cropping a bit more off your image before wiping and see if it helps?
Skywatcher 190MN, astro modded Canon 700d, cls ccd, or Ha or Oiii filters, guided by OAG, ASI120, PHD2
mikey2000
Posts: 9
Joined: Tue Nov 08, 2016 10:04 am

Re: Wipe module leaves bands at edges

Post by mikey2000 »

Thanks for the tip!

I use 'interesection mode' in DSS when stacking so I wasn't really expecting any edge artifacts.


However.... Cropping just a few pixels from all for edges made a *big* difference. (I cropped 50px approx from each edge, it's not much loss from a 6mpix image)

Good stuff!
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