User Links for
 bbrence







CURRENT MOON
(North America)
History
205 Entries
04/22/14
04/19/12
08/08/11
08/04/11
08/02/11
07/27/11
07/09/11
07/07/11
07/02/11
05/31/11
05/16/11
05/01/11
04/23/11
04/18/11
04/11/11
02/28/11
02/02/11
01/22/11
01/10/11
09/26/10
09/25/10
09/13/10
09/06/10
09/05/10
09/04/10
09/02/10
08/26/10
08/25/10
08/24/10
08/18/10
08/16/10
08/14/10
08/12/10
08/06/10
07/30/10
07/28/10
07/25/10
07/20/10
07/15/10
07/07/10
07/06/10
07/04/10
06/14/10
06/12/10
05/17/10
05/14/10
04/24/10
04/17/10
04/16/10
04/10/10
04/02/10
04/01/10
03/23/10
03/21/10
03/18/10
03/07/10
03/06/10
02/21/10
02/19/10
02/18/10
02/13/10
02/10/10
01/12/10
01/09/10
12/23/09
12/22/09
12/20/09
12/11/09
12/10/09
12/01/09
11/29/09
11/26/09
11/25/09
11/24/09
11/23/09
11/22/09
11/20/09
11/19/09
11/15/09
11/13/09
11/01/09
09/28/09
09/26/09
09/20/09
09/07/09
09/06/09
09/04/09
09/02/09
08/31/09
08/28/09
08/21/09
08/20/09
08/17/09
08/13/09
08/09/09
07/31/09
07/30/09
07/23/09
07/22/09
07/20/09
07/17/09
07/14/09
07/11/09
07/10/09
07/03/09
07/02/09
06/30/09
06/27/09
06/15/09
06/10/09
05/30/09
05/28/09
05/23/09
05/20/09
05/17/09
05/15/09
• 05/09/09
04/30/09
04/26/09
04/24/09
04/21/09
04/19/09
04/18/09
04/17/09
04/15/09
04/11/09
04/06/09
04/04/09
04/03/09
03/30/09
03/27/09
03/12/09
03/06/09
03/02/09
02/26/09
02/20/09
02/17/09
01/26/09
01/18/09
01/17/09
01/16/09
01/14/09
01/13/09
01/03/09
12/16/08
12/05/08
10/25/08
10/22/08
10/13/08
09/27/08
09/15/08
09/10/08
09/06/08
09/03/08
08/28/08
08/24/08
08/21/08
08/18/08
08/14/08
08/05/08
07/31/08
07/26/08
07/22/08
07/19/08
07/15/08
07/14/08
07/13/08
07/11/08
07/09/08
06/30/08
06/27/08
06/17/08
06/13/08
06/12/08
06/09/08
05/30/08
05/25/08
05/15/08
05/14/08
05/11/08
05/08/08
05/06/08
05/02/08
04/26/08
04/25/08
04/21/08
04/20/08
04/18/08
04/17/08
04/16/08
04/15/08
04/12/08
04/11/08
04/08/08
04/04/08
04/02/08
02/23/08
02/20/08
02/19/08
02/18/08
11/30/-1
11/30/-1
11/30/-1
11/30/-1
11/30/-1
    
Saturday, May 9th, 2009
 First light (deep sky) on my Orion Starshoot II imager, on my new Celestron CG-5 mount.   Back to the drawing board.  I must have done something wrong.   I did a rough polar alignment.....I think I was reasonably close.  The scope found M64 (the Blackeye galaxy) without fanfare.
 
I decided to experiment with a 30 second exposure, and set the camera to record 20 frames.  All seemed to be going well.  The frames were recorded.....although frame #2 doesn't want to open.  And I inadvertently stopped the capture at 19 frames.   Then I tried the same 20x 30seconds on M65/M66.   That also seemed to go well.  
 
I can see that my polar alignment was a bit off, but nothing like the issues I was dealing with, with my old alt-az NexStar mount.
 
As this was the very first night out with the Starshoot, and in the interest of learning, I did not take any darks....nor did I use the cooling function on the camera.  Apparently that was a mistake, but theoretically, I should have been able to get a decent image without either.
 
Here are the results.
 
1. 18 frames aligned and stacked in Maxim DL -No processing
2. From absolute trash to a recognizable image.....not good, but vastly improved.  Paint Shop
    Pro Photo to darken (hide the airbrush strokes) and hide the large smudge, MS Paint
    to airbrush out the hot pixel streaks, Photo Shop Carboni Tools to clean up.
3. Cropped
 
* Where did all those weird artifacts come from in the aligned and stacked image.......obviously I did something very wrong somewhere in the process.   I am not sure if there was a problem in capturing the images or in the aligning and stacking process.   Frustrating!
 
The stars are a bit square, even in the aligned and stacked image, but I think that is my scope and/or my focus.   Don't think it's the camera's fault.
 
* PROBLEM SOLVED.......WELL, MORE TO THE POINT, PROBLEM UNDERSTOOD.  NEIL HEACOCKS FIGURED IT OUT.   BECAUSE I DIDN'T TAKE AND SUBTRACT ANY "DARKS", THE IMAGES CONTAIN 'HOT PIXELS'.   THE MAXIM DL SOFTWARE TRACKED THE 'REAL' STARS TURNING THE HOT PIXELS INTO STREAKS.
 
 
 


Image Gallery For This Session
M64 01 M64 02
M64 03
   

M64_01.jpg
Click picture above for larger version
If the picture seems too bright or too dark, try adjusting the brightness below.
Brightness:
|
  



Comments:
On 05/13/09 at 04:59pm Barry wrote:
Got togther with Neil and figured out the smudge was a dust particle on the camera....on the filter over the chip. The above aligned and stacked image, when processed for color, and cleaned up a bit without the smudge and artifacts, would have been okay. Moral: make sure the camera is clean and Take "darks"

Also this was only 18 useable subs at 30 sec per sub. 50 subs at 60 sec per sub should produce a better result. A night without a full moon wouldn't hurt either.

On 05/11/09 at 02:59pm Neil Heacock wrote:
Dark subtract won't remove the smudge. Flats will though. But it would be even better to find the problem and clean it I think,

-Neil

On 05/11/09 at 02:16pm Barry wrote:
How right you are!!! I finally figured that out.....or rather Neil figured it out. No, it was my first time with this camera, and in the interest of a couple of quick captures, I neglected to take and subtract any darks. I also didn't plug in the electronic cooling on the camera.

The only mystery yet unsolved is the large dark spot left and below the DSO. It is in the same spot in a capture of M65-M66 I shot the same night (also with hot pixels). I hope it's not a smudge or problem with the camera chip. Hoping it's just dust on the scope lens. Wonder if "dark subtract" will remove it?

On 05/11/09 at 11:25am Jeff wrote:
Hi,

Those colored streaks in the stacked version look like hot pixels to me. Did you shoot any dark frames to go with the lights? If you did and used them see if using standard deviation with the darks helps.

Jeff.



Add A Comment:
Your Name (optional):

*Your Comment:



CAPTCHA Image   Reload Image
Enter Code*:


NOTE: Comments are moderated and do not post immediately.



© 2008 Triad Technology Systems | www.triadtechsys.com