Atik Cameras Forum

Images => Solar System Images => Topic started by: riklaunim on April 28, 2012, 06:56:31 pm

Title: Titan Testing
Post by: riklaunim on April 28, 2012, 06:56:31 pm
I'm testing a lot of equipment lately for my "planetary" book. Among cameras I have Atik Titan mono. It's not a typical "planetary" camera but it's also advertised as such. It seems that DS cam makers don't get the requirements for "planetary" cameras. A guider is not equal to planetary camera.

So at start something very bright, Sun in H-alpha from a 35 mm Lunt:

(http://www.rkastrofoto.appspot.com/site_media/astro/orig/sun-24-04-2012/titan1.jpg)

(http://www.rkastrofoto.appspot.com/site_media/astro/orig/sun-24-04-2012/titan3.jpg)

Now that works very well. It's very bright so the histogram is easily filled.


Now planets, a hard target, Saturn at f/20 with C11. ORGB image (Orange longpass as luminance) to make it look decent:
(http://www.rkastrofoto.appspot.com/site_media/astro/orig/saturn-27-04-2012/atik-orgb.png)

The orange channel:
(http://i45.tinypic.com/2z7o1vt.jpg)

That was all captured in Nebulosity. In Artemis Capture with the "fast" 15 FPS mode frame quality ended up very bad: http://i50.tinypic.com/ie2tfd.jpg (and it's underexposed as we can't use long exposures for planetary imaging).

It may look like Saturn but the actual efficiency of that camera was/is very low. 16-bit low gain cameras aren't good for planetary imaging as there is no exposure time to fill the histogram, and the framerate is limited by sending overgrown numbers. I was using 0,1 - 0,2 sec exposures with Atik Titan, and 0,03 sec exposures with DMK21AU618 operating at 8-bit + with higher gain (and better sensitivity of ICX618).

To overexpose red channel in Titan I would have to use more than 1 sec exposures: http://i47.tinypic.com/vx2s9l.jpg which is insanity ;) while for a DMK it looks like so (orange channel, lower gain in this case): http://i47.tinypic.com/2ldhxy9.jpg

Just after Titan recording I made some f/20 and even f/30 Saturn images using DMK21AU618. Here are f/30 examples (captured at 30 FPS, 30 ms exp. Orange and ORGB):
(http://www.rkastrofoto.appspot.com/site_media/astro/orig/saturn-27-04-2012/f30-orange-2149.png) (http://www.rkastrofoto.appspot.com/site_media/astro/orig/saturn-27-04-2012/dmk-big-q7-orgb.png)

The seeing was very good in both cases. So if you want a real planetary camera you need to... think different  ;D
Title: Re: Titan Testing
Post by: riklaunim on April 29, 2012, 05:20:32 pm
And a guide star finding comparison (http://www.rkblog.rk.edu.pl/w/p/qhy5-and-atik-titan-guide-star-finding-comparison/) - for that it works nicely :)
Title: Re: Titan Testing
Post by: bwa on April 29, 2012, 10:46:31 pm
Nice Saturn images!  I'd be happy with even the top two images.  You must have a fairly stable atmosphere?

bwa
Title: Re: Titan Testing
Post by: riklaunim on April 30, 2012, 11:05:14 am
At that night it was very good. DMK allowed to do even f/30 images (which is very rare for Saturn). All those 16-bit low gain cams aren't good for such imaging ;)