Celestial hemisphere:  Southern  ·  Constellation: Fornax (For)  ·  Contains:  NGC 1365

Image of the day 12/28/2022

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NGC 1365 | The Great Barred Spiral in Fornax, Kevin Morefield
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NGC 1365 | The Great Barred Spiral in Fornax

Image of the day 12/28/2022

Getting plate-solving status, please wait...
NGC 1365 | The Great Barred Spiral in Fornax, Kevin Morefield
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NGC 1365 | The Great Barred Spiral in Fornax

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Description

This lovely barred spiral is 11' in apparant diameter and resides 56 million light years away.  This is the first image I've posted using BlurXterminator and I think it did a great job.  A few things related to BXT and Russell's other products:

- I typically do a Luminance master wtih all subs after initial culling and then another with only the sharpest half or so.  In this case I had 95 subs below 1.8" and 65 below 1.6".  My typical process is the blend the sharper data and the full data set using a luminance mask.  Since the brightest areas have a larger sample size of photons they can withstand a smaller dataset and still maintain SNR.  The background and faint areas need sharpness less and the additional photons more.  I ran BXT on both the full dataset and the sharp dataset and found that the full dataset looked better.  I think that makes sense in that I gave it a higher SNR dataset to work with and that was more important than the data being a bit sharper to start with.  In this case the difference was small: The sharp master measured 1.44" and the full dataset came in at 1.50".  

- Color subs were also sharp at 1.51" to 1.62" for the RGB masters.  I ran BXT on the RGB master as well prior to combining with the luminance data.  Deconvolving color data does not fit the prevailing wisdom but I think things are changing.  I did this because I wanted the color detail to match closely to the very detailed luminance data that had recieved BXT.  BXT is much more gentle on noise than traditional deconvolution.  Also the NoiseXterminator tool is very good so I felt that it would be a net positive to run BXT on the RGB master.

- Most bright galaxy cores can benefit from some amount of HDRMT.  Two problems with HDRMT: 1) you don't want to hit stars with it because they get bigger and 2) it often over darkens the dust lanes in the galaxy core.  To resolve those problems I ran StarXterminator on the luminance master after BXT.  After stretching, I created a preview on just the galaxy and then ran HDRMT on the starless luminance with Gaussian 5, 6 levels, and "to lightness" and "lightness mask" checked.  I used the Substitute With Preview Script to add my HDRMT'd galaxy back into the original background.  The effect was too strong so I blended it back into the original 50/50 using Pixelmath.  [Orginal*.5 + HDRMTverion *.5]  To put the stars back in I screen-blended the stars-only version with my 50/50 HDRMT version.  The pixelmath on screen blend is ~(~starless * ~stars_only)  SIDE NOTE: you can find all of the PhotoShop blending modes converted to Pixelmath syntax here: https://pixinsight.com.ar/en/info/articles/7/pixelmath-blending-modes.html

Otherwise the processing was pretty straightforward.  SPCC was used for color calibration.  Finishing touches to color and curves were done in Photoshop.  

To make the galaxy detail more the focus of the image I cropped it heavily.  I like the wide field too so I uploaded that as well.  

I'm being a bit hedonistic going after all of the big name Southern objects right out of the gate but I didn't want to waste the good seeing we were having.  But In between these big guys I'm focusing on PN searches to hopefullly add to the PaMor Catalog!

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    NGC 1365 | The Great Barred Spiral in Fornax, Kevin Morefield
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    NGC 1365 | The Great Barred Spiral in Fornax, Kevin Morefield
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    NGC 1365 | The Great Barred Spiral in Fornax, Kevin Morefield
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    NGC 1365 | The Great Barred Spiral in Fornax, Kevin Morefield
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Title: Uncropped

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Title: Luminance Without BXT with HDRMT

Description: To help get an idea of what BXT did in this image I'm adding this Luminance master with no BXT. I just stretched it, ran HDRMT, blended that back at 50% and adjusted black point. This one measured 1.5" FWHM.

Sorry if the crop is a bit different...

Uploaded: ...

F

Description: Better saturation

Uploaded: ...

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NGC 1365 | The Great Barred Spiral in Fornax, Kevin Morefield