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JB80
28-11-2012, 02:21 AM
This is my first attempt at M45 and considering the subs I'm surprised by the result, it's not perfect by any means and I did get sidetracked creating a spike tool whilst processing but it's better than I thought. I'm not sure how much more could come out of it as it is the processing which I find the hardest so if anyone wants to have a play just ask and I can put the original stacked .TIF in dropbox or something.

There are 36 minutes of 30 second subs at ISO800, f5.6 and about the same number of darks.

Any comments and advice is more than welcome as I'd love to improve it if I can.
:)

ourkind
28-11-2012, 02:32 AM
Very nice stars Jarod the colours are beautiful, I think you can enhance and stretch the image further to highlight the reflective dust. Great angle too. Thanks for sharing :)

edit: I stretched it some more to highlight the dust, obviously the quality of the jpeg is not so good.

JB80
28-11-2012, 03:10 AM
Thanks Carlos. :)

I see what you mean, I know stretching is one area I can do better with. I was being a bit cautious as I wasn't sure if it was all the dust or not.

ourkind
28-11-2012, 03:18 AM
My pleasure plus we're all learning :) I'm yet to point my scope and camera at M45, if it wasn't for that damn Gum Tree!

Check out this APOD http://apod.nasa.gov/apod/ap120903.html it really shows off the dust and just how far you can go :)

JB80
28-11-2012, 07:12 AM
It was something I meant to shoot ages ago but having nice dark skies on our Scotland trip I made sure I could have a crack at M45 even if the moon wasn't the best for it.
No gum trees at least.

I had another go and it brings more detail out but it starts to get that painted look to it. My eyes are starting to look like computer screens but I'll revisit it tomorrow if I get a chance.
Am I right in thinking that I could isolate the stars and just work on the background and then combine the images again?

I must add a thanks to Sheeny for his tut on making diffraction spikes.:thumbsup:

Larryp
28-11-2012, 07:17 AM
Looking nice, Jarrod:)

JB80
28-11-2012, 07:33 AM
Thank you Laurie.
:)

ourkind
28-11-2012, 08:25 AM
Here's a tutorial I found on mask layering provided you're using photoshop http://m.youtube.com/#/watch?v=Yie4TDdVO6g&desktop_uri=%2Fwatch%3Fv%3DYie4TDdV O6g
More of his tutorials are found here... http://myastroimages.com/
The one you touched up looks great!

Varangian
28-11-2012, 09:25 AM
That's a nice get mate, beautiful little suns you have there too.

JB80
28-11-2012, 07:31 PM
Thanks John and Carlos again, I haven't come across that site before but bookmarked it now.
I never think of looking on youtube for tutorials but it's probably a better way to go through the work flow, I'll check it out this afternoon.

EricB
28-11-2012, 08:38 PM
It's a great looking shot Jarrod!

Eric

RickS
28-11-2012, 08:54 PM
Nice work, Jarrod!

The amount you can stretch the image will be limited by the signal to noise ratio (which will usually be lowest in the darker parts of the image.) If you stretch too much the noise will start to become visible and will look objectionable. The cure for this is more exposure time ;)

alistairsam
28-11-2012, 09:59 PM
Very nice jarrod
What mount and scope did you use and are these guided or unguided?
Reason I ask is that with slightly longer subs you could get quite a bit more detail and guiding will help with that
But I wonder what the blue overlay on the brighter stars are
I thought it could be collimation but its only on the bright ones
Very nice effort though
Look forward to more
Cheers

JB80
28-11-2012, 11:11 PM
Thanks for the comments Eric, Rick and Alistair. :)

Rick, that's what I'm worried about with the stretching as it's easy to go to far. Next time I'll try longer exposures and more of them.

Sorry I should of said what gear I was using in the first post, it was my 450D and 75-300mm zoom lens mounted on the Polarie.

I could of gone for longer subs but I had left the AAA batteries inside for the remote timer and I could see the weather closing in so settled on 30 second subs. I really wanted to gather more data but it didn't work out that night.

The odd effects I assume are from the lens not being very good, the original subs are horrible with bad flaring and are a bit purple so I think there is some chromatic abberation? and possible internal reflections with the lens(possibly sensor flare even?). I have read it's not a great lens and am starting to see why.

I'll try again from home when I get a chance for longer exp and more of them but I won't have the nice dark skies that I had.

alistairsam
28-11-2012, 11:31 PM
ok makes sense, that did look like CA, but the diffraction spikes threw me off.
I just read your first post mentioning the spike tool!!
try and dither if possible, that will make a big difference when stacking with removing noise. That way you can stretch more.

JB80
29-11-2012, 02:09 AM
It was part of the reason I added them, to give the eye something else to look at on first glance, plus it was a bit of "just because I can" too. :D


Is dither the Bayer drizzle setting or the X2,X3 drizzle or is it something completely different?