This was taken using a SW120 ED refractor and celestron nightscape . 16 x 5min exposures, 2x2 binning( about 2.6Mp res) stacked and some processing in astrofx then final processing in PS. had to filter out some of the noise . I think I will have to up the exposure and get more subs to get a better picture. I think this subject needs more aperture at about this focal length to gather more light in a shorter time. Maybe a fast newt might be the next purchase?
regards philip
Did you bin only your chromiance data (RGB), or your Lum as well? Don't bin the latter - you will lose your resolution. Or are you using a OSC and software binning?
Only the other day another member said he needed a fast Newt. APOs
may well produce great images, but sometimes that extra aperture can
be invaluable. Anyway, good job 5ash. I've been longing to image The Helix, but the weather still won't allow it.
raymo
Did you bin only your chromiance data (RGB), or your Lum as well? Don't bin the latter - you will lose your resolution. Or are you using a OSC and software binning?
Hi Barry ,
It's a one shot colour , I tried 10 minutes at full resolution and stretching brought the inevitable noise of two few photons. That's why I tried 5 minutes at 2x2 binning to get more signal at the expense of resolution. Perhaps I should have tried 10 minutes at 2x2 with more subs at the expense of less sleep!
Regards philip
Only the other day another member said he needed a fast Newt. APOs
may well produce great images, but sometimes that extra aperture can
be invaluable. Anyway, good job 5ash. I've been longing to image The Helix, but the weather still won't allow it.
raymo
Thanks Raymo,
Have followed your imaging and expect your capture of the helix will be much better than my attempt
Regards philip
My contribution:
a) the image is very nice, with good color
b) to enhance the nebula, it seems you clip the black and white.
c) to filter noise I am using the Fitswork 4.0 option blur - wavelet noise filter that is similar to wavelet of Registax. Its performance is better than PS. Try it, it is free.
In PS I am having a good result in filter the noise channel by channel, with differrent intensity.
d) perhaps a larger number of subs can improve the ratio signal/noise.
My contribution:
a) the image is very nice, with good color
b) to enhance the nebula, it seems you clip the black and white.
c) to filter noise I am using the Fitswork 4.0 option blur - wavelet noise filter that is similar to wavelet of Registax. Its performance is better than PS. Try it, it is free.
In PS I am having a good result in filter the noise channel by channel, with differrent intensity.
d) perhaps a larger number of subs can improve the ratio signal/noise.
Thanks for the tips Jorge, in fact I did use the PS filter by channel. First time I've tried it . Came apon it by chance.
Regards philip
The same in sharp. After apply the noise filter in one channel, I apply a little sharp and a small reduction of brightness.
Those actions enhance the color and the shape of stars. For shape, the green channel is more active.
As for noise, Richard did over 20 hours and his was still noisy. I haven't had a chance to have a decent crack at it yet but my 1 hour test was absolutely terrible with noise using the ED100.
