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[Sticky] Colored centering of the stars, align channels
with some stars I have a color border all around. Is it possible to calculate this out when stacking with APP? Or could this function be added by an update?
ASI 183 MC Pro color cam
The photo is enlarged to see it better.
This is with one-shot color or using filters?
Mm, difficult one for me, you could try to experiment with the pixel interpolation in tab 6, unfortunately I have not a good understanding of which one would help you in this case so it requires some trial and error. If that doesn't change anything, I'm happy to take a closer look at the data later.
I tested the pixel interpolation all through. But it brought no improvement.
I think that comes from the atmospheric dispersion. If the object is not so high.
Would be cool if APP could optimize that. Since this is currently not possible with any other program. As far as I know.
Hello Daniel, try experimenting with the values in diffraction protection. Start the integration with automatic settings and then read the value in the terminal output. Then stop integration and increase the value manually. If that doesn't help, try adjusting to values between 2 and 5. Depends on the optics used.
Maybe play with rejection algorithms.
I hope this helps.
With best regards Henry
I experimenting with diffraction protection. But with no attitude I had an improvement.
But I found a way with APP.
So that it goes quickly, I have only stacked 10 pictures.
In tab 2 "Calibrate" I checked "Align channels" at the bottom.
Then all images were saved as a calibrated FITS file.
After that I reloaded and stacked these FITS in APP.
Without "Align channels"
With "Align channels"
It would of course be great if APP could do this process in one. So you don't have to cache and reload the images.
Ok, that is a really good call there, it seems it's actually meant specifically for this. Sorry I missed that, I've never had this issue and I also don't save my frames in between so I never saw the explanation to that tool. Thanks for experimenting and letting us know! I'll ask if this can be done more in line with the regular workflow.
Unfortunately, this is not possible without intermediate storage.
If the box "Align channel" is checked and the integration is started directly, the effect will not be visible.
Here again with 6.5 hours exposure time reworked.
Without "Align channels"
With "Align channels"
The M104 is very low at my location. (20-25 ° altitude) This shows the effect well.
Yes it's not possible right now. I've spoken with Mabula about this and it's not as easy as it may seem to integrate that function in the workflow. It is on his to-do list though so it should be possible in a future version.
I did the same thing with the galaxy from the first post.
Hello Daniel, just saw your Youtube video on the subject. I hadn't thought about the option Channel Alignment, I have activated it by default. If you want to combine images from different cameras, you can still get colored artifacts around stars, even if you use the Channel Alignment option. I had this problem when I combined DSLR images with images from my ZWO CMOS camera. Then the diffraction protection helped. 😉
ok cool. Thank you 🙂
For the others... here is the video. But it is in German.
That's very interesting. Thank you for the feedback.
Have you tried the channel alignment with the final integrated image ?
No, I didn't try that. But think that the quality is better to align the individual RAW images.
I've made this thread into a sticky, great stuff. I'll also go through the other stickies that are outdated and such.
Can this be done for the integrations of each filter? Could I do my normal workflow, where at the end I get an integrated image for each filter, and then reload those files back into APP as lights, and then check "Align Channels" and then Save Calibrated Images, and use those in the RGB combine tool?
Mmm, good question. I never tried that, but my guess would be that you should be able to do that when it's RGB in the end.
I definitely see this shooting mono through filters - I will give it a try and see if this workflow solves my problem as well.
Thanks for this sticky post! I have always ticked the box thinking it would already do that in auto-mode... Good to know, how it really works.