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Lovely detail in the main galaxy and in the three tiny ones above it. Very nicely acquired and processed. Very sharp.
Some tiny things that might make it even better:
- There are some repeated hot pixels. Since their position changes strongly with reframing between subs (a very good thing), and you have 15 subs, statistical data rejection (the simplest is median combine; we use a winsorized sample which is more powerful) will get rid of them very easily.
- There are some black spots which are due to hot pixels in the darks. These go away if you use statistical rejection when making your master dark.
- There are some dark haloes around the brightest stars produced by deconvolution or sharpening. There are many "anti-ringing" tricks for controlling these.
- There seems to be some misregistration due perhaps to changes in focal length and other higher order distortions between frames. A simple shift and rotate won't get rid of these. You might need more sophisticated registration software.
Once again a lovely image.
Very best,
Mike
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Hi Mike thanks for showing such an interest and passing on some tips it is always appreciated
That program of yours winsorized looks interesting i will have to give it a go sometime I've been using CCD stacker registration doesn't work all that well i have noticed specially with slight rotation.
My odd often dark pixels i think can be attributed to the calibration data not matching i didn't have any for this target but i used some from a later date. It was worth doing but left those artifacts.
Im still trying to master deconvolution making two sets one for stars the other for points of interest and layer masking them together.
Would be interested to know some tips on "anti-ringing".
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Hi Michael,
that's an excellent sharp image.
I hope you can add some RGB data at a later time?
Is that a stock GSO RC14 or does it have modifications?
cheers
Allan
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Thanks Allen my GSO14 has only one modification being a 3d printed baffle tube extension to fix issues with stray light. There are lots more things i would like to do but don't get the time
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It is looking pretty good so far  Looking forward to a full colour rendition.
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Unfortunately its getting a bit to late for M83 will try again next year.
