M16

[ChrisV]

Trying out my new filter - an optolong l-extreme

M16 taken with an OSC camera
8" F5 GSO newt & ASI071, 175 x 6min subs over 3 nights
www.astrobin.com/b3sfse/

Thanks, Chris

[raymo]

Great job, but it doesn't do much for the pillars.
raymo

[Atmos]

The pillars don’t seem to be popping a lot but you have captured a lot of Nebulosity. How do you find the filter so far? I’ve been eyeing that one off.

[ChrisV]

Point taken about the pillars. There's more Ha in them before I attack it. So the lack of pop could be my hack processing. Or the filter. I'm not sure.

This is the first object I've tried since getting the filter. I think it's working better around oiii with the narrower bandwidth there - compared to the duo filter. Might try another object I did last year with the stc duo filter

[Atmos]

Chris has been kind enough to let me have a play with his data, the colour balance that I've ended up with is probably closer to a SHO than the HOO I was expecting where the Ha has turned out orange as opposed to red. That's most likely my colour balancing so far but this has just been a quickish play.

Attached is a crop around the centre and the link [url=https://www.astrobin.com/full/ueuqxn/0/]HERE[url/] is to the full frame with a slightly different stretch.

End to end processing was around 25-30 minutes with a bit of playing around in between. I could have just a much better job on the stars as they look a bit funky but that takes more effort than I could be bothered with at the time :lol:

From what I can tell the filter appears to work quite well and isn't showing any weird halos which is nice to know. It's another tick for me in the direction of purchasing one to beat some of the light pollution.
Processing is as follows:

- Make a preview in an area that appears to be a neutral black spot
- Background Neutralisation on that area
- Make a preview in the central bright region (around the pillars)
- Color Calibration using a white balance on the pillars preview and turning off Star Detection. Set the black reference as the black preview
- RGBWorkingSpace to set all to 1.
- Extract CIE*L twice. Once for a L and another for stars
- On the Stars image I played around with Morphological Transformation with a Morphological Medium Operator to correct for the star shapes (tracking errors). Takes a bit of trial and error and fattens the stars slightly but does make them rounder.
- DynamicPSF on both L & Stars to have two difference PSFs for deconvolution.
- Run Deconvolution on Stars to fix some of the error caused by Morphological Transformation (Using the PSF from Stars)
- PixelMath ($T^.1) on both images
- StarNet on L and then StarNet with "Create Star Mask" on Stars
- PixelMath ($T^10) on L
- Deconvolution with 50 passes (with PSF from L)
- PixelMath ($T^.1)
- PixelMath (L+Stars)
- PixelMath ($T^10) on L
- Histogram Transformation both the RGB and L to get the black point at the bottom of the histogram and the mid point 1/4 of the histogram
- LRGBCombine to blend the L and RGB together
- Use L as a Mask, open Color Saturation, set at 0.25 and saturate to your hearts content :)

I could have created a RGB stars image and set the colour balance to get nice RGB stars to add in, could have also used masks to protect the stars during this process or just removed the RGB stars entirely and then added the L in to a starless RGB (makes subtle looking stars) but it was all more work than I wanted ;)

Hope this gives some of you some potential processing ideas :)

[ChrisV]

Wow! Thanks Colin. Looks like the issue was my lousy processing. I'll look through the processing procedure you have kindly posted.

[LewisM]

I wonder how processing together straight OSC RGB data and Duo Band narrowband would do? I’m going to try

[strongmanmike]

Hmm interesting filter, the concept sounds pretty cool. Looks like it might require the application of some different processing routines though..?

Nice work

Mike

[ChrisV]

Thanks Lewis & Mike - processing this is a big learning curve for me and Colin has really helped me with this. I've had a go reproducing Colin's advice, attached. Stars not great, but they can wait.

Lewis - I used combined OSC and Duo before (with the STC duo filter). I usually end up just using the duo data - and the OSC for stars

[Nikolas]

http://www.iceinspace.com.au/forum/attachment_browse.php?a=261232


I reckon the processing has a lot to do with it, this was with my ts130 refractor and the L-enhance, I'd love to do a side by side comparison with this and the L-extreme but it's an expensive comparo

[ChrisV]

Very nice Nik! I switched from the STC Duo to this as I felt that the OIII on the duo filter was too broad and not as selective, but I don't know how that compares to the l-enhance filter

Revised with slightly better stars
www.astrobin.com/uzwzm1/

[Craig_]

Interesting discussion in this thread. I've been really struggling to get some good seperation between Ha and Oiii with my recent M16 data taken with the L-Enhance.

[Ant0nio]

Hi Chris,
Congrats on your final image & thanks for posting, this is a helpful thread.
Colins input is testament to the value of this forum.
Cheers,
Tony