Trouble stacking Ha images in Pixinsight - *** Error: Unable to find an initial set of...

[MartinFransson]

Hi guys!

Trying to stack a bunch of Ha-subs I got last night. I guess they are a bit faint but I have no problem seeing the stars in them. However, PI refuses to stack more than a few of the 39 subs.

First I tried with BPP, but that didn´t work well. I used the calibrated and debayered images i StarAlignment and when I raised the Ransac tolerance and added some noise reduction I got it to register a few more but still not good. I get the error message: "*** Error: Unable to find an initial set of putative star pair matches"

Any ideas? I use a Baader 12nm filter to capture them with my Canon 550D. Exposure 600 seconds at ISO 800 and f/5 scope. Had no problems stacking widefield images taken at f/4 but of course they were a bit brighter.

Any general tips for stacking DSLR Ha images?

One of the subs attached.

IC405-HA-150PDS_LIGHT_600s_800iso_+6c_20161127-22h24m11s864ms.CR2

[D4N]

If the problem is faint stars try reducing Log(Sensitivity) under star detection, this allows PI to detect fainter stars, yes reducing increases sensitivity.  You can also lower Detection Scales to increase the number of stars it can use.

 

Under star matching you can increase the triangles per star setting to increase the likelihood of finding matches.

 

Adjusting these settings will likely increase processing time,

 

[MartinFransson]

On 2016-11-28 at 22:03, D4N said:

If the problem is faint stars try reducing Log(Sensitivity) under star detection, this allows PI to detect fainter stars, yes reducing increases sensitivity.  You can also lower Detection Scales to increase the number of stars it can use.

 

Under star matching you can increase the triangles per star setting to increase the likelihood of finding matches.

 

Adjusting these settings will likely increase processing time,

 

Seems to work like a charm, thank you!

[D4N]

Glad you got it working