UPDATE FROM MABULA
I have had a very rough 2 months unfortunately health wise. I was struck 3x in a row with bacterial infections. The second infection occurred  after a routine hospital checkup and I became very sick. I had to rest and take a lot of antibiotics. Once I was recovering and restarting work 1 month ago, I again became sick. The infection was not yet gone, so even more antibiotics and rest was needed. Needless to say, it took a lot of my energy and I needed a lot of rest.
Finally, the infection is really gone and my energy is coming back step-by-step now and I have started work again. I am terribly sorry to have kept you waiting for support. I will address all outstanding questions and e-mails step-by step and will be on the forum daily from today.
APP 2.0.0-beta47 will come soon as well, a lot of work was already completed before I became very ill, so the release is also nearly ready for you. Beta47 will be much faster actually. Many workflows will be more than 2x faster, mosaics can even be 10x faster than before because registration really received a major boost... all compared to beta46. Â Before I release it, I will make sure that everything is working properly and then I will release it.
Hello,
For some time I have been trying to solve a banding artifact occurring in my highly stretched (OIII and SII) data. I thought for a while that this was an interference pattern between the NB filters and the ASI 1600MM Pro (Mono).
Tonight however I realized that the pattern appears with variation on each individual sub-frame only after registration. Occurs in both normal and mosaic mode, though mosaic produces more curved or even pinwheel artifacts. It is less pronounced but still visible in the masters.
Also less pronounced in other viewers or processing software, but still appears if I stretch far enough
It is not present in the calibrated frame:
Any thoughts?
Thanks,
-Chris
Hi,
I have this happening to me now as well. Â The images look great (HA-OIII extracts of Ha and OIII). Â After registration the image develops vertical banding that are most pronounced in the center of the image, and wither out towards the edges. Â I am unable to understand why this is happening.
Have you solved this or has anyone given helpful tips?
thanks
raed
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Interesting. Could you upload the integrations (2 I assume) and the masterbiad, masterdark and masterflat (for me to check) to our server?
Go to https://upload.astropixelprocessor.com and use upload3 as username and upload3 as password.
Create a directory named “raed-stripesafterregistration” and upload in there. Thank you!
Raed and Vincent,
After looking into this more I believe it to be moire, an interference pattern introduced by resampling, rescaling, or rotating images. There are several threads on the cloudy nights forum discussing it.
In my images I notice that a more pronounced moire pattern occurs when the images are zoomed out, but fades when I zoom in, suggesting the resampling artifact is introduced by the display rather than the actual data.
There is a fainter moire pattern that persists, however, and can appear later in post processing when aggressive stretch or noise reduction masking is applied to the fainter NB channels. This I believe is introduced when the images are resampled for registration. Zooming in alot I can see stair step aliasing artifacts in bands across some images that correlate. I will try to post some pictures later.
I have had some luck reducing it if I use a different interpolation method in PI for registration, but I'm not sure how to implement this in APP.Â
From what I read, the lancos interpolation is more prone than others to moire, and cubic is suggested. Also good calibration frames seem to help.
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Let me know if you have any luck or other insights.Â
Â
Chris
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Thanks for the insight Chris, I will ask Mabula what he thinks about that.
