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davidpretorius
17-08-2005, 09:20 AM
Hi guys, my first attempt at dso prior to tracking (fingers crossed) and prior to a stable platform for my toucam in afocal setup and in the longer exposure settings.

I am building one of these to attach the toucam to the eyepiece but to both 1.25" and 2", so please excuse the hand held 2 second exposures

http://www.astronomyonline.com.au/images/ph047m-0.jpg (javascript:help('../images/ph047l-0.jpg');)

No black screen done, but will have to get rid of those coloured pixels
12mm ep, aprox 100X mag

Gee this is fun!

h0ughy
17-08-2005, 11:07 AM
you have a bit of camera noise there david

ving
17-08-2005, 11:30 AM
how does one reduce noise... less exposure time i think... or lower iso...cant remember.
well done tho :)

davidpretorius
17-08-2005, 11:53 AM
a long road ahead, and lots of improvements to be made, but (a big but), lots of fun with the journey!

iceman
17-08-2005, 12:13 PM
Reduce noise by:

- Stacking lots of shots, increases the signal to noise ratio.

Reduce noise and hot pixels by:

- Taking a dark frame and subtracting it from your image

Good first effort David!

davidpretorius
17-08-2005, 12:17 PM
thanks mike, yes i need to have a steady mount and a few images to stack. registax kept losing the reference, as my hand was not steady enough.

how do you take a dark frame?

asimov
17-08-2005, 05:11 PM
Nice first DSO shot David. I have no capability to take shots like that, only planets. I'm asuming it's omega centauri?

seeker372011
17-08-2005, 05:22 PM
There is another way to get rid of hot pixels if you didnt take a dark frame, but ist time consuming -simply use the clone stamp tool in Photoshop and stamp out all the hot pixels..you do seem to have a few though

(dark frame is one or better a median stack of an odd number of images with essentially the camera lid on)

BTW why not try prime focus photography instead of eyepiece projection-prime focus is easier.You wont need the holder gizmo then

davidpretorius
17-08-2005, 05:52 PM
tuc 47, asimov, purchase a toucam, hold it up to the eyepiece and take a video! come to snake valley, and we will plug this sucker into your 12.5 big boy!

seeker, prime focus is working very well, except for taking wide shots like this at 100X, mr toucam in prime focus works at 208X (1250mm / 6mm ).

does anyone know how to use prime focus and get less than 200X?????

asimov
17-08-2005, 08:33 PM
I can already take video with my Kodak. Just never tried a DSO yet. Jupiter works ok, sort of....usually seeing conditions stuff the video up so I dropped the idea.

seeker372011
17-08-2005, 09:01 PM
you will need a focal reducer for that..still I would have thought you would be able to frame a globular like Tuc 47 with the TouCam even otherwise