INtegrating subs with different scopes - why not working?

[magnusl]

Hi!

I am trying to combine subs I have taken with 2 different scopes: one is a C8, and the other a refractor, 100 mm f/7, with a wider FOV. I am trying to integrate the subs, and as far as I understand, this could be done with star alignment, choosing a sub with higher resolution (here a C8-sub) as reference. Right?

However, whichever way I try to do it, it fails. Staralignment registers the subs with taken with the same scope as the reference image, failing the others.

What am I missing? A number of subs are found here:

https://www.dropbox.com/sh/fs744ujp8oed79d/AACfnztnt-E98N8km8Tv2dUBa?dl=0

The ones that says "Iris" are from the C8, the ones saying NGC7023 are from the refractor. Any help on this is warmly welcome.

Best,

Magnus

[pfile]

i managed to get it working with the following settings. i think one big problem is that the images are noisy and the star detector is picking up on hot pixels. also possibly due to distorton in the wider field image, the ransac algorithm is not able to make matches properly, so i increased the tolerance. i also told the star detector to detect less sharp stars, and try to find dimmer stars.

i was able to register NGC7023_Light_300_secs_2018-09-05T22-24-20_001_c_d.xisf to iris_Light_300_secs_2018-09-08T00-20-45_001_c_d_debanded.xisf and vice versa with this icon.

rob

[magnusl]

Thanks!!

It's interesting that it is problematic in this case, my first attempt to combine images from my two scopes. Thing is, I have so far not experienced any problem in aligning subs from the two sopes separately, not a single fram dropped/failed. But when combining it becomes difficult. I guess there are more things at play here than I understand.

So a question: is this not a case where one could switch on Frame Adaptation? (I'm not sure what that does, but read somewhere that it should be on in a case like this)?

Magnus

[pfile]

frame adapation just fixes the brightness between frames. it's for making mosaics...

rob

[msmythers]

Magnus

Most parameters have an explanation of the function available by hovering the mouse pointer over the parameter area. Also with StarAlignment there is the full documentation available within the program. You can access that by the open square with the folded corner icon at the bottom left of the tool.

Here is both for the Frame Adaptation parameter.


Mike