Santa Barbara Instrument Group ST-8300C, Operating Manual

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SBIG ST-8300 Manual
automatically. Use the Focus command in the Camera menu and set it up
in the Focus Setup dialog as shown below:
Click OK and the camera will go into Focus mode. You’ll see image after
image appear in a single window with a new image about every second.
The images will vary slightly from image to image, mostly in the random
background noise but in general they’ll all look a lot like
Image 1 . You’ll
also notice a new Focus Mode dialog appeared.
Here’s a brief description of the key items in the
Focus Setup and Focus
Mode dialogs.
Exposure Time – You’ll be able to see most objects in a 1 second
exposure. Use shorter exposures (down to 0.10 seconds) for faster
rep rates when focusing on bright stars or longer exposures when
trying to center dim objects.
Frame Size – Planet mode allows you to select a portion of the CCD’s
field of view ( FOV ) for faster rep rates due to smaller downloads.
It’s great for focusing the telescope on a star. The other three Full
settings all show the FOV of the CCD but are slower than Planet
mode because there’s more data to download.
Full-High uses high-resolution mode to show you all 3326 x
2504 pixels. Full-Low uses low resolution (3x3 binning) which is
faster and more sensitive since there are fewer pixels to download
and the pixels are larger. Finally
Full works in conjunction with
Planet mode and the Camera Setup such that when the camera is
set to Auto resolution mode Full uses the low-resolution mode for
faster downloads then switches to high-resolution for Planet mode.
Dark Frames – For most objects you won’t need to take dark frames in
Focus mode to frame and focus the object because the exposures
tend to be short and the build up of dark current minimal. On
some dim objects though, checking this item, which uses
dark
subtracted images for Focus mode can help to pull the object out
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