Focusing Your Camera - Celestron Nightscape 8300 Manual

once nightscape is attached to your telescope and powered on, you are ready to use
AstroFX software to control the camera and begin taking images.

foCusing your Camera

Before you begin taking images, it is important to take time to carefully focus the
camera. to focus nightscape from AstroFX's snAP screen (see Figure 7):
1. set the Exposure duration to a short interval (e.g., 1 second to start). You want
the star to appear bright enough to effectively focus, but not so bright that pixels
are saturated. remember, the longer the exposure duration, the longer it takes to
see the result of a change in focal position.
2. set the Resolution to Half or Quarter to reduce download time.
note: resolution of Half (or 2x2 binning) will combine two adjacent pixels to effectively
increasing the pixel size by four times. likewise Quarter resolution increases the
pixel size by 16 times. while this will increase light sensitivity it will also reduce the
resolution of the image. so "binning" is a good method for focusing, because image
acquisition speeds up greatly and gives you greater sensitivity to see faint out-of-
focus stars. Binning can also be used to increase light sensitivity when imaging at
long focal lengths such as f/10. Go to the nightscape web page on the celestron web
site for more information on focal length and binning for celestron telescopes.
3. set the Exposure type to Focus and press the Start Imaging button.
4. now center a moderately bright star in the frame and slowly adjust focus until it
is visibly sharp in the downloaded image. Hit Abort once the star is centered.
5. set Subframe to Set with Mouse and use the cursor to draw a box around the star.
(see Figure 5).
11.
www.celestron.coM