StarTools

Ok , well not 100 percent Startools but let's say 95 percent.

I did the complete run through Startools. But i could not get it sharp, not sharp enough to bring out the details.
So i use PI and use Starnet 2 to create a starless image, and a starimage.
Then in Gimp i used Unscharp mask , that worked pretty well, this on the starless image only . Changed a little bit the color ,left a tad of green in .Saved it as a fits file and went to ST to use the Layer module and putted it together. I did not alter anything in the star image.

I like it also. Many details, false color Hubble palet.

In Startools i binned to 50 percent, wiped it , stretched it, contrast module, sharp module, color module, took the first SHO matrix, superstructure isolate, used shrink to get a bit rid of the many stars, denoised it. Even use the Flux module , but that did not help much to get a sharp image.
I did not have any issue with the blue color though, the blue was there in the color module, i changed a tiny little bit in Gimp but really not that much.

Scope was a 130 mm TS photoline with a Focal reducer brought to F5,6/ 3 evenings, Ha 4h42 - OIII 5h30 and SII 4h30
Screwed up my framing a bit on the second session but i had still enough to get a descent IC 410 out of it.

My main question here is , why could i not get the sharpness out in Startools. Also HDR did not do much here...

Must say i like this SHO stuff...My former Wizard was not too bad, and thisone worked out even better.....but... i need 3 evenings ...

Some of you might know i have a full PI version too.

Looks pretty good, Freddy.

I did see you had a PI edit a couple days ago on CN. You are way ahead of me there, as I actually haven't even bothered trying to learn how to really stretch or post process in PI. Unless you leave things default or effectively autostretched, even GHS really wants you to do iterative histogram stretching, right? I'm a hard pass on that.

I'm pretty sure I can still see the sponge-like star removal holes, but really only when clicking to make things bigger.

If you feel like sharing out the original stacks, we can always try our best with 100% ST versions to see how things compare and if PI/Gimp are giving you correct results (if one cares, that is), or if ST is lacking anything, other than perhaps fully variable tricolor hue mapping. In PI I would presume that's a pixel math formula for the channels.

Here is the link to the files

https://www.dropbox.com/scl/fo/kuqrdpj5 ... 75ftl&dl=0

Anyone who likes to process them, most welcome

Be aware , the second stack is too much tilted...i loose quite some field there, unfortunately...

@Mike in Rancho
Stretching in PI is not that easy, personally i start with an arcsinstretch, then a HGS or Histogramtransformation. It does not always work out well. Stretching in Startools is much more intuitive

Hey Freddy,

Well I barely understand the controls and graphs I'm looking at for PI stretching. It's not even really like Gimp, where the levels and curves tools are quite a bit more obvious.

You have some nice files there. Kind of too bad about the camera/field rotation issue, as there are some nice outer structures that unfortunately would get cut off with cropping. I tried a rotate in ST to try to get the most acreage retained, but lost a lot of the top that way.

It has a quite different look with the stars left in, I'll say that. My first edit went overboard on saturation, so the whole thing looks like the paint department at Home Depot exploded. I'll have to work on something a bit tamer and see what comes out.

Thanks Mike for trying,

Yeah a real pity of the framing. When i first noticed it, i felt like slamming myself. Alot of the otherwise beautifull surroundigs are a bit lost.

And yes it comes out a bit muschy in Startools, doesn't it. Splitting the image in starless and stars and using unscharp mask for the starless image in GIMP worked surprisingly good. Dunno why.

But i also learned that my 130 mm with FR really works well. It acts like a new telescope. I have some distortion in the upper right corner, but you hardly notice it. I assume it is some tilt, cause the other corners look ok.I am very pleased witht the scope

Hi Freddy,

this is what I came up with:
Disclaimer: I have absolutely no experience in processing mono/SHO data sets nor data coming from refractors. My first thought was: "Where are the spikes"...

This is a pretty straight forward processing. No fancy stuff. SHO matrix was one of the first in the list. I wasn't able to reduce the stars as much as I wanted (your renditions appeared like that would be important to you). But I somehow hit a wall where the stars didn't get smaller/dimmer unless I accepted lots of ringing.

DimSmall and Saturate in SS were applied.

I think Freddy's right on the ST rendition appearing more blurred compared to PI. Freddy's PI rendition on Astrobin has more edge to it. Where this comes from I don't know.

Not bad, Stefan! I kind of like the aqua for the OIII.

I too checked out your astrobin for the PI edit, Freddy. Indeed things look rather sharp in comparison. But I really don't know how to evaluate sharpening as it relates to reality, especially unsharp mask. Post-tracking, I did play around a bit with the wavelet sharpen in ST, and the unsharp mask in Gimp before I scaled and converted. I did not apply anything though. Unsharp mask looks pretty good - in some areas - but again don't know if it's too much. That might be even moreso if it was being applied to star removal pixels.

The unsharp mask was, however, causing artifacts around background stars. No protective mask like ST's sharp, I guess.

Anyway, I took another run at it and kept things tamer. Relatively, of course. Googling IC 410 and hitting the images button brings up a rather gaudy menagerie, almost painful to look at.

First I did go ahead and rotate in order to try to get the largest area rectangle for preserving some FOV with the crop. Then a bin, wipe, optidev, contrast with only 20 or so locality, HDR a bit tweaked - low on the tame amount but a raised dark enhance (I know Freddy likes that), then SVD, Color, and Denoise. No SS. No Shrink. Other than I did try Shrink dering only on a bunch of the tiny stars. That's it.

Thanks for letting us try it out, Freddy.


I might have used too much blue bias, or perhaps a late gamma reduction would have helped.
EDIT: decided I had to make that late adjustment.

Oh one other thing I did notice in the astrobin, Freddy, was maybe something a little awry in the star "put back" (I have no idea what the right term is)? In addition to being very muted, intensity-wise, they are oft multicolored, say blue with a red ring or the reverse. Kind of like little cookies or jelly danishes?

Stefan B wrote: ↑Wed Jan 17, 2024 8:23 pm Hi Freddy,

this is what I came up with:

IC410_Freddy.jpg

Disclaimer: I have absolutely no experience in processing mono/SHO data sets nor data coming from refractors. My first thought was: "Where are the spikes"...

This is a pretty straight forward processing. No fancy stuff. SHO matrix was one of the first in the list. I wasn't able to reduce the stars as much as I wanted (your renditions appeared like that would be important to you). But I somehow hit a wall where the stars didn't get smaller/dimmer unless I accepted lots of ringing.

DimSmall and Saturate in SS were applied.

I think Freddy's right on the ST rendition appearing more blurred compared to PI. Freddy's PI rendition on Astrobin has more edge to it. Where this comes from I don't know.

Very nice Stefan. I like the coloring
Yes the ST rendition comes blurry. I don't know where this comes from either. HDR seems not to do a great job , nor the flux module.
Yet, it is easily to solve with unsharp mask in eg GIMP.

As for star reduction, shrinks works well, but in PI i use a script, so not the default procedure. The script makes a mask of very small stars , they are then protected against the schrinking. And that works really well. I see it all to often, that in ST the small stars seem to dissappear, but the big ones still remain too big.

Mike in Rancho wrote: ↑Thu Jan 18, 2024 8:37 am
I too checked out your astrobin for the PI edit, Freddy. Indeed things look rather sharp in comparison. But I really don't know how to evaluate sharpening as it relates to reality, especially unsharp mask. Post-tracking, I did play around a bit with the wavelet sharpen in ST, and the unsharp mask in Gimp before I scaled and converted.

The unsharp mask was, however, causing artifacts around background stars. No protective mask like ST's sharp, I guess.






Oh one other thing I did notice in the astrobin, Freddy, was maybe something a little awry in the star "put back" (I have no idea what the right term is)? In addition to being very muted, intensity-wise, they are oft multicolored, say blue with a red ring or the reverse. Kind of like little cookies or jelly danishes?

Dunno if unsharp maks can harm, Mike . Well unless you applied too much. It is tedious, you have to find a balance, but imho it brings out alot of details that are in the data.

The stars, well, guess my second revision on astrobin was not too bad, however there are some light pinkish stars in the more or less centre of the nebulae that i would have prefered to be at least white. That i don't know where that comes from either.

But well overall , i am very pleased with the image.

For now , we may have another clear night tomorrow, still don't know what i am going to do. Moon is in the sky, so maybe i just should redo my OIII perhaps, make a new stack and integrate it just to get a better bigger view, as the picture contains alot of nebulosity around the object which i find quite nice.
I could try M42 too, but without any filters, moon in the sky and the color cam, it might come out not that great....

Well OIII and the moon don't often get along. Probably true even of 3nm, but mine are more like 6-7.

I'm not sure what to think of sharpening in general, let alone unsharp mask (assuming there's even a difference).

In a way, they kind of seem like contrast changes. And while no external data is being brought in, there's still a bit of tricky manipulation it seems. Don't know what it means, if anything, other than we know it's not data restorative like deconvolution.

For scientific purposes, I opened a picture of my backyard in Gimp. Copied it and applied a Guassian blur, then subtracted that off the original, and then took that result and added it to the original. Yep things looked "sharper," though the power wires ended up with an electrified appearance around them.

I know there's also a scaling that can be done but I didn't think up a way to implement that (in retrospect maybe the opacity % would have worked for that). In any event, why does blurring something then subtracting and adding back create a "sharpening"? Maybe subtracting off the blur leaves just the strongest elements of the image for pasting back onto the image?