Here is one of my first attempts at astrophotography with stacking and processing - before this I was just taking single shots and playing around with focus, exposure, and ISO, etc. I'm pretty happy as a first serious attempt.
Stack of 17 1 minute subs @ iso1600 with master dark processed in nebulosity and photoshop. Unmodded canon 70d, 10" CF Newt on NEQ6 pro, synguider on Orion 80x400.
Just curious as I'm fairly new to all this - how come you're using short subs at ISO 1600? Not that noise seems to be a major issue, but would have thought that because you're guided you'd go longer subs at a lower ISO...?
Asking because I eventually want to upgrade to a guided 10" f/4 Newt myself. Not anytime soon, but eventually.
That's a great effort Rod.
Chris, the reason behind the shot subs is because Eta is a very bright DSO (second only to M42), so shorter subs will help to prevent the core from being overexposed, esp when you are shooting at f4/f5.
Cheers
Bo
That's very punchy Rod, love it!
I think you may have your green and blue channels mixed as the nebulosity in the central region should have some blue but not visual green
Thanks
Still learning about photoshop so my have got the colour balance a bit off. I might have another go at it and see.
Regarding length of sub that seemed about right and I was not 100% sure of the guiding. I did manage to get one exposure that night guiding off what I think was noise which produced a really weird result. I've got a shot of Orion which I'll post shortly which was using PS HDR option to reduce core blowout.
Cheers
Rod
No no, I get that - I was wondering why you'd use ISO 1600 for 60 seconds instead of ISO 800 for 2 mins or ISO 400 for 4 mins. Perhaps because it's first light and you just wanted enough for a decent test...? I'd love to use lower ISOs and longer subs but I'm shooting unguided, so not an option.
Quote:
Originally Posted by traveller
That's a great effort Rod.
Chris, the reason behind the shot subs is because Eta is a very bright DSO (second only to M42), so shorter subs will help to prevent the core from being overexposed, esp when you are shooting at f4/f5.
Cheers
Bo
No no, I get that - I was wondering why you'd use ISO 1600 for 60 seconds instead of ISO 800 for 2 mins or ISO 400 for 4 mins. Perhaps because it's first light and you just wanted enough for a decent test...? I'd love to use lower ISOs and longer subs but I'm shooting unguided, so not an option.
You're shooting with a Nikon so using a lower ISO is fine, but they are using a Canon with a large read noise, so shooting at 800-1600 is helpful to overcome the read noise and get the best image possible.
