NGC4565 with QSI

[allan gould]

From my location in BrisVegas, this galaxy was just skimming a large tree in my neighbours yard. But despite the low level I was pleased to get the final luminance image from the skyglow. It 14x5min with QSI583WSG thru a 10"SCT with f6.3 FR. Starwipe really helped me eliminate a gross gradient from the final shot. Levels and curves in PS then grad removal with Starwipe. A big thanks to Ivo at www.siliconfields.net.
Allan

[h0ughy (David)]

Al it looks a little too processed or clipped?

[allan gould]

Agree Dave but had to do that to get any image at all from it being so low, swimming in the soup and flitting in and out of the tree leaves.

[h0ughy (David)]

do you have a soup shot to compare?

[jjjnettie (Jeanette)]

You've got some lovely detail in the galaxy itself Allan.

[tonybarry (Tony)]

Allan, that looks great. Good work with the QSI.

Regards,
Tony Barry

[David Fitz-Henr]

That's a nice image Allan, especially considering the challenging conditions.

[allan gould]

Originally Posted by h0ughy

do you have a soup shot to compare?

Just for you David

[h0ughy (David)]

Originally Posted by allan gould

Just for you David

Ahh i see you have pushed the red channel far too far.....

[RobF (Rob)]

Seriously though - great shot Allan - have never imaged, but saw once at Cambroon through Ron's dob
Pretty low to N even for Bris, so heroic stuff shooting through all that sky glow

[h0ughy (David)]

image processing commandment n0 1 thou shall not clip thy image

can i see some chicken and corn soup

[peter_4059 (Peter)]

Nice shot Allan for something that is so low in the North.

[RobF (Rob)]

Originally Posted by h0ughy

image processing commandment n0 1 thou shall not clip thy image

can i see some chicken and corn soup

Me senses a miraculous PixInsight Dynamic Background Extraction reprocess in the wind......

[JD2439975 (Justin)]

Got an eye on this one myself, a classic "flying saucer" galaxy.
Actually several very nice galaxies in that little patch of sky.

Allan it's certainly a challenge to wipe the soup off low, faint objects & for an hours worth of data that's looking pretty good.

Keep at it.

[irwjager (Ivo)]

I always love seeing people tackle the not-so-usual suspects, despite clearly sub-optimal conditions. Well done!

[allan gould]

Thanks for all the kind comments. I may try to get some more data but I really think that data combined with better processing may be my real saviour.
But thanks for the input as its really appreciated.
Sometimes is just good enough to notch up your own photo of an object no matter if its not a masterpiece - at least its yours and you know what you had to go through to get it.

[h0ughy (David)]

Originally Posted by allan gould

Thanks for all the kind comments. I may try to get some more data but I really think that data combined with better processing may be my real saviour.
But thanks for the input as its really appreciated.
Sometimes is just good enough to notch up your own photo of an object no matter if its not a masterpiece - at least its yours and you know what you had to go through to get it.

Didnt mean to offend Allan - merely give some constructive help

[multiweb (Marc)]

Very nice details in the dust lane. Impressive.

[allan gould]

Originally Posted by h0ughy

Didnt mean to offend Allan - merely give some constructive help

David - none taken at all. Your observations were spot on and constructive.
Appreciate the fact that you took the time to comment.

[irwjager (Ivo)]

Originally Posted by h0ughy

Al it looks a little too processed or clipped?

Actually David, that's most likely StarWipe's doing.
Allan mentions there was a gradient present before he put it through StarWipe as a last step, so that means that the image can't have been clipped before it was put through StarWipe.

StarWipe maximizes contrast, removing any background light such as natural skyglow, Gegenschein etc. StarWipe does not clip however; it will never subtract a bigger value from a pixel than is the background light level (unless some extremely aggressive settings are used).

It will make images appear unnatural to some, but that is easily corrected by adding back a baseline level. The consensus for natural skyglow seems to be between 8-10 for red, green and blue. Personally, I think doing so is a waste of dynamic range as it defacto reduces contrast, making intricate detail harder to see. When it comes to aesthetics however, the debate's been going as long as there have been 'submit' buttons...

Looking at the final result (which is pretty damn detailed!), and taking into account the sub-optimal conditions, I can't really fault Allan's processing.