56 • Celestial Photography
Planetary or Lunar--
f/20 is a great way to image the planets and features on the moon. With the
PixCel CCD camera and optional Color Filter Wheel, it is easy to take tri-color
images of planets also. When imaging the planets, very short exposures are
needed. Many cameras have trouble taking images under .1 seconds. The
PixCel camera can image at .01 seconds exposures due to the design of the
CCD array. The exposure lengths range from .03 to .1 seconds on planetary
images. Focus is critical as is good atmospheric conditions. Generally you
will take one image after another until one looks good (see AutoGrab feature in
the PixCel Operating Manual). This is due to the atmospheric “seeing” condi-
tions. For every 10 exposures you might save 1. To image at f/20 you need to
purchase a 2x Barlow and a T-adapter or Radial Guider.
Imaging at f/20
1
Optical Tube Assembly
12
Pulstar Illuminator
2
Secondary Mirror
13
Illuminator (Microguide Eyepiece only)
3
Secondary Mirror Retaining Ring
14
Reducer/Corrector f/6.3
4
Fastar Lens Assembly
15
T-Adapter
5
Tricolor Spacer Ring
16
Cross Hair Eyepiece
6
T-1 ¼” Adapter
17
Visual Back 1 ¼”
7
IR Cutoff Filter
(for use with Color Filter Wheel)
18
Star Diagonal
8
PixCel CCD Camera
19
26mm Plossl Eyepiece
9
Rear Cell Counterweight
20
T-Ring (for 35mm SLR Camera)
10
Radial Guider
21
35mm SLR Camera
11
Microguide Eyepiece
22
2X Barlow Lens
For more information about the above accessories refer to the Optional Accessories section at the end of this
manual
Figure 7-6 -- This figure shows the many accessories that can be used with the Fastar compatible G-8N telescope in its
various optical configurations.
