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Omaroo
06-04-2008, 05:14 PM
At last I've managed to:

a) get the time

b) avoid the clouds and rain

c) had skies good enough to bother with

d) get proper polar alignment on my little Tak SkyPatrol-II

I used StarTarg and a webcam to drift align, and managed to take single images with the clock drive keeping stars round for up to 8 minutes. Not bad. No guiding. RA motor only. This mount has been hard to align mainly because the 355mm focal length of the FS60-C scope makes it a long-winded task if you use a 12mm illum. reticle. Painful. Webcamming it made all the difference :)

Anyway - here are my first attempts with it and the even littler FS60-C. The camera is a Nikon D40 that desperately needs to have the IR filter ripped out - happening soon. Typically these are 4 minute single-frame images with a dark subtracted. ISO800-1600.

Now that I have the polar alignment kinda sorted with this mount, and its really short focal length, (355mm) I'll take multiple images and stack next time around.

1) Eta Carinae

2) Triffid & Lagoon

3) Omega Centaurus

4) a 490-second exposure (8 minutes) unguided and unprocessed - I just let the RA motor run to see what happened. Pretty yukky - but should process-up OK.

dugnsuz
06-04-2008, 05:22 PM
Lovely sharp images Chris, and nice FOV from the Tak.
Doug

iceman
06-04-2008, 05:50 PM
Nice work chris. Is the mount sturdy enough to have guiding via a guidescope? Does it even have a guide port?

Omaroo
06-04-2008, 05:58 PM
Thanks Doug! :)

Thanks too Mike. No - it's a very basic (but well-built) unit. You plug it in and turn it on - and the RA motor moves at sidereal rate - that's it. I have to say that I'm impressed with the 8-minute exercise - though not perfect by any means it ain't bad & especially being so small.

peter_4059
06-04-2008, 06:11 PM
Nice collection of images Chris. It sure is satisfying when you nail the polar alignment. I would love to have a permanent setup to avoid the drift alignment step.

Peter

gbeal
06-04-2008, 07:17 PM
And to be fair, 8 minute subs is plenty long enough anyway. Great stuff Chris.

Omaroo
06-04-2008, 07:23 PM
Thanks Peter!! :)

Gary - you're right. 5-6 mins is all I need once I sensitise the camera and take multiple subs. 8 mins still gives near-acceptable widefield tracking - which is as good as I've gotten on a G-11 and EM-200 before. Neither of those two gave me any better unless they were guided.

It's so nice to have the little Tak working like it should.:thumbsup: As always - thanks for your help!!!