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View Full Version here: : First light 16" ASA f3.6


alocky
17-04-2017, 01:18 PM
You'd think changing OTA on a well tuned mount would be relatively painless, but Murphy's law and O'Flaherty's corollary definitely define one of the fundamental truths of the universe.
The balance point of the OTA is about 2" away from where I need it to clear the dome shutter motor, the new ASA focuser won't sit still long enough for the SGPro autofocus routine to work, the mount doesn't like slewing at a speed over 1 deg/sec with the larger load, and of course it's cloudy.
So without autofocus, and with slightly dodgy tracking I managed to get 80 minutes worth of 2 min Luminance subs on M83.
I need to re-do the flats - as this lot haven't done a great job and I've had to clip a lot of the fainter parts of the image, but the scope shows a lot of promise. Damn, it sucks the light in - in 40 minutes it went considerably deeper than my older 10" at f8 managed over a couple of nights, and the initial sub length of 5 minutes was far too long.
Anyway - if it was easy I suppose it would be boring!
Higher res at astrobin:
http://www.astrobin.com/292123/
cheers,
Andrew.

RickS
17-04-2017, 02:26 PM
That must be quite a beast, Andrew! Look forward to what it can do. The M83 data is a good start.

Cheers,
Rick.

alpal
17-04-2017, 02:39 PM
A nice start Andrew,
The DDM85 should be able to track without the Lodestar
especially if you shorten the subframes to say 2 or 3 minutes.

cheers
Allan

gregbradley
17-04-2017, 06:30 PM
A great start. It sounds like a wonderful setup. There is always a learning curve with a new scope and mount.

Greg.

topheart
17-04-2017, 06:53 PM
Hi Andrew,
Great to see the first light!!
Congratulations....I reckon it will be a killer combo!!

All the very best.
Cheers,
Tim

Slawomir
17-04-2017, 07:07 PM
Awesome telescope (and the mount)!

A great start and we all look forward to seeing your astro images taken with your new scope:thumbsup:

Mighty_oz
17-04-2017, 09:04 PM
Great start there.

markas
17-04-2017, 10:34 PM
When you get it all sorted out, the DDM85 should easily be good for 10-20min subs unguided - but balance is absolutely critical.

f/3.6 certainly speeds things up.
Great start.

Mark

Peter Ward
18-04-2017, 09:44 AM
16" F3.6? Seriously?

Very impressive piece of kit! I look forward to the results when you have tamed the calibration issues.

clive milne
19-04-2017, 10:41 PM
:thumbsup: Congrat's mate...

strongmanmike
20-04-2017, 05:23 PM
Congrats on you first light Andrew! :) A formidable scope, you should be creating some great images in no time :thumbsup:

Mike