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ChrisV
26-02-2018, 11:22 PM
3 hours on Eta Carina from 2 weeks ago. 132x (edit: not 192x) 90sec subs on ASI071 80mm F5.9 refractor. Just left it running all night - my scope seemed to keep focus !! A victory.
Captured with APT, processed in PI. I've binned 2x2 and compressed it to get the file size down

Fernando
27-02-2018, 03:46 AM
Hi Chris,

Looks great to me. Congratulations.

Fernando

glend
27-02-2018, 07:53 AM
Chris the 80mm seems to provide good image field of view for Eta C. Is that reduced to f5.9 or the native focal length of that scope?

xelasnave
27-02-2018, 08:00 AM
Nice one Chris.
Alex

PKay
27-02-2018, 08:22 AM
Great image Chris

You may have 3 hours, and now add another 30...

Try 240s exposures.

Well done.

ChrisV
27-02-2018, 11:54 AM
Native F5.9. 472mm focal length. The FIV is just perfect for this beautiful nebula

ChrisV
27-02-2018, 11:59 AM
Thanks Alex & Peter, yes I'd like to get more on it. Maybe get some more next month before it goes too far west for me.

I'm not sure longer subs would help. I used Shiraz's spreadsheet calculator and 60 - 90 sec seems to give near-optimal SNR with this camera, focal ratio etc. Anything above that doesn't improve it much and will just cause more saturation. It does take a long time to register/integrate etc with hundreds of subs though - suppose thats the rub with CMOS cameras ?

PKay
27-02-2018, 02:01 PM
Hi Chris

In an effort to get better star colours, I have been experimenting with really short exposure times (less than 10s) and low gain (50 for the ASI1600).
It does work.

So the plan is:

For the stars: Take 100subs @ 10s. Get the darks and bias at the same setting. Integrate these into one image separately.

For the feint stuff.
Do the same for 120s and then 240s.

So we end up with 3 images for the final integration.

Kiarano
04-03-2018, 03:29 PM
Impressive work Chris.Thanks for sharing.

yoda776
09-03-2018, 11:05 PM
Impressive image Chris. Thank you for sharing from an aspiring astrophotographer :)

LostInSp_ce
10-03-2018, 10:29 AM
That's a beautiful Carina Chris. Well done :thumbsup:

jenchris
10-03-2018, 11:07 AM
Nice take. If you're unhappy with the depth you can soon add more lights or ha lum.