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FrancoRodriguez
03-12-2023, 04:58 AM
Any constructive criticism greatly appreciated--I'm. new to galaxy photography and didn't realise just how different and complex it is.


link to astrobin
https://www.astrobin.com/dpna83/


I took the frames a couple of months ago but with a new 5 month old baby girl, time is at a premium!


Used Adam Block's M51 tutorials quite heavily including continuum subtraction for H alpha. I used Russ Croman's BXT,NXT and SXT extensively. Frankly, I tore my hair out trying to get the H alpha to work but I'm happy with the results apart from the star colours, which I did stretch and process separately. Not sure what went on there.



I'm not very used to imaging galaxies but my new 2550mm f/7.2 might change that. This was an LRGB image comprising of approx:
25x480s Lum
15x480 R,G,B each
25x900s Ha


Planewave 14" CDK

FLI proline 16803
chroma filters
Ultrastar pro OAG
ASA DDM85

Bortle 3 sky in rural QLD

alpal
03-12-2023, 06:01 AM
Hi Franco,
well done!
that's a fantastic result but one I would expect
considering your seriously top equipment:
from a Planewave scope to an FLI camera and DDM mount.
I assume it was unguided with the DDM85?
Your image processing is great too.

What is there not to like?
You mentioned star colours and I see they almost all have a Red
colour except for their central White areas.
Maybe others can chime in on that?
It sometimes helps star colours if you take extra short 30 second
or 1 minute exposures and copy and paste those in for the bright stars.

cheers
Allan

FrancoRodriguez
03-12-2023, 09:19 AM
Thanks for the kind words! Yes...it's true that with higher end gear comes a higher level of expectation from everyone (myself included!) I'm cool with that, and determined to get better and processing. But I'm now a workman who can't blame his tools any more! Haha



I'm now sure that the issue was exactly what you said--very high K values in the brighter stars on the lum channel. I'll learn from that. Unfortunately starxterminator plucked out the H alpha/red globules from the continuum subtraction. Way too early in the process for me to care about it any more!


Have a happy Christmas:)

strongmanmike
03-12-2023, 11:52 AM
A great start, with a great rig Frank :thumbsup:...onwards and upwards from here :)

Mike

alpal
03-12-2023, 03:26 PM
Hi Franco,
yes high K values will give White stars -
those bright stars have most likely exceeded the well depth
of your CCD pixels which means that all information is lost.
Only a short exposure will remedy that.
It's easy and quick to do on any target -
just 1 frame each of RGB for say 30 seconds.
In Photoshop -
select color range
highlights
modify
expand by say say 2 pixels
feather by say 2 pixels

copy and paste the stars on to the main picture.
Suddenly the center of all stars have color. :)

cheers
Allan

gregbradley
03-12-2023, 05:53 PM
That's a terrific image. I like the processing and colour as well.

Greg.

FrancoRodriguez
03-12-2023, 06:21 PM
Thanks for the tip. Very simple and elegant...I don't know why I didn't do it ages ago!

Peter Ward
03-12-2023, 09:21 PM
Superb. I'm simply enjoying the view. :thumbsup::thumbsup:

Ryderscope
03-12-2023, 10:25 PM
That is a superb and very elegant Sculptor Galaxy :thumbsup:

Stephane
04-12-2023, 03:10 PM
A superb telescope is nothing without skilful acquisition and processing. You have nailed this one with a crisp and detailed galaxy!

Personally, I find the star glow slightly on the heavy side, but regardless of that, this is still a 10/10 image imho. Well done.

Stéphane

Startrek
04-12-2023, 09:20 PM
A beautiful image with exquisite detail
It’s a joy to scan around and find so many tiny faint galaxies with extraordinary detail considering their size and magnitude
Well done indeed !!

Martin

joshman
05-12-2023, 08:44 AM
absolutely amazing. the resolved detail is phenomenal.


I'm looking forward to the next image!

telecasterguru
25-12-2023, 02:17 PM
Beautiful image and nicely processed.

CoolhandJo
31-12-2023, 05:26 PM
Very nice! should be IOTD IMHO