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SimmoW
04-07-2014, 12:32 PM
My most technically challenging shot yet.

I updated the Synscan firmware to 3.35, that seems to have fixed the way-off goto accuracy of the scope. So finally, I can just plug in an object and it slews to dead-on, amazing.

I also got the polar alignment fairly accurate at lower altitudes, but when the scope slewed right up towards the zenith, it lost a lot of its accuracy & I could only take 20-30 sec subs. Is that expected? should I have done another polar alignment of a star higher up?

Anyway, I took 120 (one hundred and twenty!!) subs at only 20 secs, as a fun test to see how much I could extract. not too bad I think, though longer subs appear much more effective, from the other shots I've seen here.

Reduced the ISO to 400 from 800. Think I'll go bak to 800!

For first time I rotated the focuser to get a better composition. Risky/scary due to moving the image around, but think it was worth it.

A disaster happened though, somehow the camera got into a weird Jpeg resolution mode, without my knowledge, so I ended up with 120 pretty small jpegs, not raw files. Grrr. It was a beyatch to stack, and had horrid artefacts and gradients. But that was good in a way, as it forced me to try using Pixinsight to stack instead of DSS. Wow, it was very effective at fixing the gradients, so here is the result of the PI process. Wide enough for you?!

https://www.flickr.com/photos/48232585@N00/14382589049

cometcatcher
04-07-2014, 12:51 PM
Some nice colours coming through Simon. Yeah if the exposure time is shortened the ISO needs to go up to compensate. Don't be afraid to stack lots of frames. 120 is nothing! Though it keeps the computer busy for a while.

doppler
04-07-2014, 01:20 PM
That sure is a wide field, must be a short focal length/fast f ratio. Looks great.

Retrograde
04-07-2014, 01:51 PM
Very nice Simon!

SimmoW
04-07-2014, 02:55 PM
thanks, yes it's a fast scope, F3.3, only 430mm F/L. I prefer the wider fields myself, since i'm just a beginner & find it powerful enough for me! It'll take me years to image most of what I'd like, before I dare upgrade.

cometcatcher
04-07-2014, 03:26 PM
Wow f3.3. No wonder the scope sucks in the nebula well. You have an excellent scope there. Like you say that will keep you busy for ages. And a tip, that scope would be excellent for closer comets. C/2013 A1 Siding Spring is coming in the next couple of months. It passes through 47 Tuc / SMC and other DSO's for potentially some awesome shots.

SimmoW
04-07-2014, 03:30 PM
thanks for that Kevin, keep us posted as to its progress and appearance, and yes by then I might be able to capture some of its beauty. It is known as an ideal 'comet catcher', like you.

Busting for my guide cam to be delivered, I better follow up next week..

cometcatcher
04-07-2014, 08:07 PM
I usually post it's progress in the Solar System forum. Here's my latest.

http://www.iceinspace.com.au/forum/showthread.php?p=1096173#post109617 3

raymo
04-07-2014, 08:14 PM
Yes, very nice Simon. Thankfully, the camera disaster can't happen to
me as I don't use raw.
raymo