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Messages - mmnb

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Bug Reports / pixel trails that follow cursor?
« on: 2019 September 01 23:14:37 »
I have PI running on a newer MacBook Air (just fine) and an older MacBook Pro where I am running into an odd problem:

I've adjusted the UI settings a bit for accessibility and see rather annoying pixel trails that follow the mouse cursor on images (they disappear after a bit).  I don't see anything similar in the forum.  Some machine info:

15 inch (Late 2013)
Mojave 10.14.6
PixInsight Core

Image Processing Challenges / Re: m8 lagoon nebula
« on: 2019 August 14 18:04:49 »
Increased saturation a little.
EDIT: Added exp stretch to brighten a bit.

Image Processing Challenges / m8 lagoon nebula
« on: 2019 August 14 17:04:08 »
C14+hyperstar+ EOS 60Da

Found my darks before I thought I could get a hold of them and indeed including them in the calibration (as recommended here: by bulrichl) really did seem to make the thin dark lines disappear (that wasn't going away, despite dithering). I'll try to post some controlled comparisons on that since there seems to be some varying advice o how to deal with Canon dark current suppression.

Nothing fancy:
Up to PCC
Deconvolution (still hard to see the effects here, very easy to overdo)
Denoising dark
Sharpening nebulosity
Star shrinking (while linear, very light)
arcsinh stretch (I liked this stretch better than the masked stretch as I seemed to be getting smaller stars and better color although the outer nebulosity was dimmer)
HDMRT (no mask, brought out the internal dark areas to look more like masked stretch)
Small L and Sat curve adjustment.

Lots of nice images out there but it seems to be in the right ballpark but would love to hear any criticism.

XISF up to PCC:

Image Processing Challenges / Re: m106
« on: 2019 August 09 16:13:56 »
I certainly will try your suggestions when I get the chance but it will be a few weeks.

Image Processing Challenges / Re: m106
« on: 2019 August 09 13:18:01 »
No need to take offense. I've tried understanding appropriate handling for these Canon cameras and a few credible sources suggest not bothering with darks.

Just to put the main conflicting source inline:
"This, along with the dark current suppression built into the hardware, removes the need for dark frames."

I have no doubt your guide describes the *correct* way to handle dark frames for calibration, but it isn't clear to me that they are *needed*. What I am trying to reconcile across sources is "is the effect of dark frame calibration clear and visible?". I don't see the answer to that in your guide, perhaps I have missed it.

Image Processing Challenges / Re: m106
« on: 2019 August 09 01:32:44 »
To be sure, this is my current pre processing after noticing the dark current is suppressed in the Canon EOS 60Da:

Biases/Flats saved in 'RAW Monochrome' readout setting in maximDL.

Creation of master bias (using super bias).

In batch preprocessing (IIRC it won't run if you try using flats without bias or dark), supply the flats (not as master) and master bias with the lights and debayer here as well.

I believe this should be fine no (no dark frames, but biases needed to divide by flat)? This correction seems ok by eye.

Image Processing Challenges / Re: m106
« on: 2019 August 08 05:23:41 »
Indeed, this was something like 30x30s exposures with dithering.  Thanks for all the cannon specific advice.

EDIT: Should add that calibration is done without darks due to the way cannon works with 'dark suppression'.

Image Processing Challenges / m106
« on: 2019 August 07 13:39:33 »
C14 Edge HD + Hyperstar + EOS 60Da

Standard preprocessing up to deconvolution, masked stretch then HDRMT (masked to galaxies) and some saturation and curve nudging.  There is a line that shows up in the bottom 6th in all my frames, not sure what the cause is there; I might try and kicking it out in cosmetic correction.   Is collimation/focus error obvious here in the cropped frame (I can see the chromatic aberration in the stars when working on the image)?  I'm trying figure out to get it fixed, right now it seems that the error is position dependent.

EDIT: Link to xsif, linear image processed upto PCC:

Gallery / Re: North America Nebula Region
« on: 2019 July 29 21:51:31 »
Very nice!
Do you mind elaborating on reasoning behind to the two background reduction steps? I always only do 'subtract', now I've only just  heard of  Carlos' method (which I can't actually find now) where he does some sort of linearization of the bg model and then only subtraction.

Gallery / Re: ngc4236 C14 hyperstar + EOS 60Da
« on: 2019 July 24 11:26:08 »
Can you clarify? This image was processed only with pixinsight.
EDIT: Ah I suppose there was another piece of free software involved in the very last step in terms of cropping and curve adjustment.  These were very very trivial changes (easily done in PI) and only mentioned for accuracy.

Gallery / Re: ngc4236 C14 hyperstar + EOS 60Da
« on: 2019 July 24 10:15:55 »
It is possible. At the time acquired this data I was using the focus routine in maximDL, and realized I needed backlash compensation.  Not sure if I fixed that before or after acquisition; I can see it now too that you point it out.  I'll keep an eye on in it as I go through my other datasets I've acquired over the last few weeks.  EDIT: I have a 'proper' focus routine in place now that moves to a focus star every 15 or so minutes and focuses via focusmax (I am still kicking the tires since the std devs in focus position seem large).

Gallery / ngc4236 C14 hyperstar + EOS 60Da
« on: 2019 July 23 23:51:39 »
Stars are rounder than last time from subframe selector stats and PSF, and seem less 'painful' visually. I hope this was a result of a tiny bit of hyperstar adjustment and persists in my other datasets I've acquired since.

This was 150s x 24, would love any advice on improving.  Sharpening with deconvolution or multiscale linear transform didn't help much, the galaxy was quite noisy so just applied gentle denoising. A touch of extra curves adjustment in GIMP.

PCC = Photometric Color Calibration

Did you also LinearFit channels before combing into RGB?

Some basic workflow on lightvortex:

EDIT: Maybe just to make sure, might be worth detailing steps you did to get image just in case there is a mistake in there. E.g. did you calibrate w flats?

Just a quick sanity check, can you post the RGB image (not LRGB) after PCC? Is there any color contrast in it?

Best I could do.  Deconvolution (really not sure if it did a whole lot), denoising, masked stretch, HDRMT (seemed to work like magic). Saturation adjustments (tried to really punch red selectively for the red hydrogen filaments. Is this way off in any way?  The weak signal in the background has some shapes that line up with the IFN in better data, tried to be honest in keeping a little contrast but very faint.

Would love to see if someone else can do much better.

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