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tornado33
02-05-2005, 08:28 AM
Hi all
A bit of a learning curve getting used to using my off axis guider/focusser on my 10 inch F5.6 scope.
http://www.aeroquest-machining.com/page9.html
For the most part found guide stars ok, though they are a bit comatic due to they being off axis, like guiding on a short line rather than a dot. I used the 12mm eyepiece and 2.8x barlow. I can guide long with confidence now.
Camera is EOS300D
The Eta carina shot is a 1120sec (18 minute) and 770 sec (12 min)shot (ISO 200) stacked with registax. Ive never taken an 18 minute shot before with the 300d .No dark subtraction. I think it is my deepest ever pic of Eta Carina.
the Omega centauri shot is a 500 and a 570 sec shot stacked.
Guiding not 100% perfect in tonights shots, gotta get used to the way the scope "handles" now, the magnification of the guider is big, the tiniest adjustment sees movement of the guide star now.
ISO 200 gives much less noise, even with shots lasting over 10 minutes.

tornado33
02-05-2005, 08:31 AM
oops I forgot to post the links
Eta Carina
http://www.users.on.net/~josiah/temp/etacarmay05.jpg
Omega Centauri
http://www.users.on.net/~josiah/temp/omega%20may05.jpg

iceman
02-05-2005, 08:47 AM
Holy cow! :eyepop: What great shots!

Excellent work Scott, I love the omega centauri shot. Send that into the mags!

gbeal
02-05-2005, 08:48 AM
Tornado,
WOW, they are spectacular, especially the deep on of ETA. Well done.
I am sure we will see more from you soon. Congratulations.
Gary

ErwinvdVelden
02-05-2005, 09:07 AM
Ah, another digital long exposure devotee!

Nice shots, Scott! You know what the next phase is, the hairy art of uncooled camera dark frame subtraction.

Cheers,

atalas
02-05-2005, 10:25 AM
Good work tornado !


Louie:eyepop:

rumples riot
02-05-2005, 10:43 AM
Those are lovely shots, well done.:eyepop:

[1ponders]
02-05-2005, 11:21 AM
Holy deepsky imaging Batman :eyepop: They are absolutely awesome. :2thumbs::2thumbs::cool2: :clap::clap::clap::clap::clap::bowd own:

tornado33
03-05-2005, 12:55 AM
Thanks
Yes I lack decent dark frame/flatfielding software that will correctly subtract dark frames from 6.3 MP 16 bit TIFF images (what I convert my RAW camera images to work with in Photoshop), without leaving coloured spots on the nebulosity areas, and that doesnt cost the earth. :)
I was expecting more noise for such long exposures, but at ISO 200 the noise suppression built in to the camera must be working at its best. :) Well done Canon

h0ughy
03-05-2005, 07:47 AM
you and that reticle eyepiece! You must be a BORG and have it fully integrated in you eye
!!!!, top work that.

:cool:

Orion
06-05-2005, 03:56 PM
Scott you out did yourself very well done! You can sure see your photos getting better and better as time goes on.

Striker
06-05-2005, 04:00 PM
Awesome....Scott.....you must be happy.

ving
06-05-2005, 04:10 PM
great shots!
:)