Problem with ASTAP3.8 with one specific file that solves with ASTAP1,26

[Roger J Boulanger]

I recently replaced ASTAP1.26 with ASTAP3.8 and it solved problems I had had plate solving some files collected from an RC20 4115mm scope running NINA.
However there is only one file I've found so far that version 3.8 cannot solve but if I run version 1.26 it solves.
I've attached the file in question. I wonder if someone could shed some light on this.

Roger

[han.k]

Hi Roger,

These cases are always interesting.

I looked into it and it solves fine if you force binning to 1. When binning is at auto=0 then the solver decides to bin 2x2 because the pixel scale is about 0.7 arc seconds. When binning is at auto there is a rule to bin as soon the pixel scale is below 1"/pixel.

I considered to add an other rule but not at this moment. I checked hundreds of images and current simple rules seems to be the best compromise. In some causes experimenting helps but the solver can not do that because it want to solve fast.

Does ASTAP work reliable with your field of view?

Cheers, Han