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[RCC] sh2-155

SHO Request for feedback Sh2-155
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Is this image oversharpened
Multiple choice poll 11 votes
27% (3 votes)
73% (8 votes)
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Chris Evans avatar
Chris Evans avatar
Hi there,

First time using the RCC thread. I've just completed a 21 hour Cave Nebula in SHO. Details and image here:

https://www.astrobin.com/jvtcv8/

This was processed using a starless workflow in PI using Bill Blanshan's unlinked stretch then GHS to make some minor adjustments to black point.  my focus was to bring out the dark dust lanes as best as possible whilst also keeping noise in check.

I sharpened this image using a combination of unsharp mask in PS, BXT and the detail slider in NXT.

If I'm being completely honest, this is more than I usually sharpen and absolutely as far as I'd be comfortable doing so. But I'm interested to hear what some more experienced imagers have to say on that. 

I'm six months into the hobby and have now been imaging in mono narrowband for about 4 months.

Thanks in advance for your feedback.

Chris
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Lasse Skov avatar
Lasse Skov avatar
Hi Chris

I won't call myself and "experienced imager" by any means but I think this is really about personal preference. I'm guilty of sometime sharpening a bit too much using BXT - but I always try to aim for something that looks somewhat "natural" (whatever that really means when we're taking narrowband).

I think your image looks really really great - but I would personally sharpen a bit less so it's not so obvious that BXT was used. But again - it's about personal preference smile
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dkamen avatar
dkamen avatar
I like it.
Tim Ray avatar
Tim Ray avatar
Hi Chris,

The image looks great. I like the sharpness (as you say), however, I think you were a touch heavy on the LHE (Dark structure enhancement), if your using PixInsight…

I run NXT between 15 and 25 on the bottom slider.
BXT I leave the top slider at default and move the Reduce halo slider anywhere  between 0 and -24, usually around -12ish. the bottom section is default.

Try LHE to help enhance the dark structure

Its a nebula. It should be softer than a lunar, solar or planetary image. If the subject supports a lot of sharpness go for it. I would not increase it any further with this image.

Hope this helps

CS Tim
Helpful
Chris Evans avatar
Chris Evans avatar
Lasse Skov:
Hi Chris

I won't call myself and "experienced imager" by any means but I think this is really about personal preference. I'm guilty of sometime sharpening a bit too much using BXT - but I always try to aim for something that looks somewhat "natural" (whatever that really means when we're taking narrowband).

I think your image looks really really great - but I would personally sharpen a bit less so it's not so obvious that BXT was used. But again - it's about personal preference

Thanks Lasse, for sure I will do a revision with less sharpening.
Well Written Respectful
Chris Evans avatar
Chris Evans avatar
Tim Ray:
Hi Chris,

The image looks great. I like the sharpness (as you say), however, I think you were a touch heavy on the LHE (Dark structure enhancement), if your using PixInsight...

I run NXT between 15 and 25 on the bottom slider.
BXT I leave the top slider at default and move the Reduce halo slider anywhere  between 0 and -24, usually around -12ish. the bottom section is default.

Try LHE to help enhance the dark structure

Its a nebula. It should be softer than a lunar, solar or planetary image. If the subject supports a lot of sharpness go for it. I would not increase it any further with this image.

Hope this helps

CS Tim

Thanks Tim, never used LHE so I'll give that a go. Cheers for your BXT and NXT suggestions. Have you had any luck with "sharpen non-stellar then stellar" in BXT?
Tim Ray avatar
Tim Ray avatar
I have played with that setting in BXT. When I did play, I saw no difference with it checked or not. So I left it default and left it unchecked. I might not have had data that benefitted from that option. I don't know. However, Play!!!! If you see a change or an improvement, go with it…

CS Tim
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