Ive been learning CCD stack and i'm pretty happy with it so far.
I've applied some deconvolution for the first time just a little to keep the stars looking reasonable.
For some reason my flats don't seem to be working very well im left with some odd vignetting issues when stretching leveling.
Image has been cropped. Unfortunately didn't get enough time for colour before the clouds rolled in.
I had a go at this with my DSLR and 8" f4 newt last year but couldn't get the detail, you've captured. My image scale was all wrong and the dslr noise too much when cropped.
What's with the rings around some of the stars? Is this from the deconvolution?
Looks like you have some very nice details in the galaxy there I was shooting M83 the other night but did not get enough data before moonrise
Thanks Luis Might be worth giving it another shot m83 has been a great target for me.
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Nice one there Michael
I had a go at this with my DSLR and 8" f4 newt last year but couldn't get the detail, you've captured. My image scale was all wrong and the dslr noise too much when cropped.
What's with the rings around some of the stars? Is this from the deconvolution?
Goran.
Yeah the odd rings are from deconvolution.
I did read that a good method was to use a standard luminance layer with good stars and a deconvolved layer blended together for good stars and detail or using masks.
But i was lazy in this shot i just made it all deconvolution, needs allot of work.
Ive never used a DSLR but year i can imagine with all the hot nights noise could be a problem.
You've got some good details. I'd just back down the deconv/sharpening a little. Good shot overall.
PS: startools is great to generate starmasks. You can then blend the fat stars back in as 'lighten' or 'lighter color'.
good shot mate.
Hi Marc, I am interested in your Star Tools approach to blend in stars-could you tip me on how you do it?
I have some exps of B33 shot at 400ISO with nice dynamic range and tight stars then some shot at 1200iso with nice nebula but bloated stars-I would like to blend the two together.
Cheers
Graham
Thanks Luis Might be worth giving it another shot m83 has been a great target for me.
Yeah the odd rings are from deconvolution.
I did read that a good method was to use a standard luminance layer with good stars and a deconvolved layer blended together for good stars and detail or using masks.
But i was lazy in this shot i just made it all deconvolution, needs allot of work.
Ive never used a DSLR but year i can imagine with all the hot nights noise could be a problem.
hi Michael,
The way to avoid rings when deconvolving is to use an inverse mask.
The concept of using stars in a different layer is mostly with narrowband images where we remove the narrowband stars and add RGB Stars to give it a more natural look.
but if its a standard RGB, just create a mask of the stars, "grow" or increase the mask by a few pixels to make sure the star is fully covered by the mask, then inverse it.
That way deconvolve will only act on the area between stars and your stars won't have rings any more.
Ive been learning CCD stack and i'm pretty happy with it so far.
I've applied some deconvolution for the first time just a little to keep the stars looking reasonable.
For some reason my flats don't seem to be working very well im left with some odd vignetting issues when stretching leveling.
Image has been cropped. Unfortunately didn't get enough time for colour before the clouds rolled in.
5x600s Luminance at F4
Try 15x4min subs Luminance and 15 darks same temp you can take your RGB another night only take flats if you have got to try without and see if needed make it easy for your self.
Your M83 is in a different orientation to mine, it must be rotating
at a hell of a rate of knots.
raymo
I think its just cos of the odd angle i had my camera at. I stopped imaging right at the meridian. BTY i like your colour M83 looking good.
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Try 15x4min subs Luminance and 15 darks same temp you can take your RGB another night only take flats if you have got to try without and see if needed make it easy for your self.
yeah your right shorter subs would have been better at f4 i only just workied out the whole SNR formula. Now that i know i should be aiming for around 2900 background ill take shorter subs.
At 600 sec for this m83 it was sitting at around 7500 average twice what i needed.
I'm having tracking issues for some reason now so might be a while before i can add some colour detail in there. For some reason i cant get round stars past 8 minutes any more.
The way to avoid rings when deconvolving is to use an inverse mask.
The concept of using stars in a different layer is mostly with narrowband images where we remove the narrowband stars and add RGB Stars to give it a more natural look.
but if its a standard RGB, just create a mask of the stars, "grow" or increase the mask by a few pixels to make sure the star is fully covered by the mask, then inverse it.
That way deconvolve will only act on the area between stars and your stars won't have rings any more.
Cheers
Alistair
Alistair im a little confused do you mean to make and mask before deconvolve in CCD stacker?
Ive only just worked out how to make inverted masks in Photo shop for the purposes of stretching fainter parts without blowing out the bright parts.
Is that similar to what you mean?
im left with some odd vignetting issues when stretching leveling.
. For some reason i cant get round stars past 8 minutes any more.
