My Equipment
The essential equipment needed for astrophotography includes:
Telescope - there are several types of scopes, the longer the focal length, the "tighter" the shot
Mount - the mount is extremely important. It must be able to track objects as they travel across the sky with a very high level of precision, during individual exposures that may last for 30 min or more.
Camera - Images here were shot with CCD cameras specially designed for this purpose. DSLR cameras can also be used, with some limitations.
Filters - Unlike terrestrial photography the light associated with astronomical objects is very faint. It may have traveled 37,000 years or more to reach us! As a result, images are captured using multiple exposures through filters to capture the RGB (Red, Green and Blue) spectra. The RGB frames are then "stacked" to represent a full color image. Many times several hours of exposures are "stacked" to resolve the fine details you can see in some of these pictures.
If you are interested in learning more, there is some great information here
Business End of RC Optical 10" Telescope
Wait a minute....whats all that stuff?
Down inside the scope you can see the primary mirror which is 10" in diameter.
From this view you see the back of the secondary mirror. The round device with the
wires is the servo which controls the focus of the system by adjusting the secondary
mirror in and out.
As you would guess, focusing is a big deal in astro imaging, and in most cases is handled
by computer. Special software evaluates a sub-image for the clarity of the stars in a picture
and automatically adjusts the focus to an optimal point.
Camera - SBIG STL 6303 with large filter wheel
The imaging train (Light Path) from the left to right is:
Telescope (Black), then
Rotator (Red), then
Off Axis Guider (Black), then
Camera Filter Wheel (Silver), then
The Camera (Silver)
AstroPhysics Mount and ATS Pier
ATS Pier, Scope Roller and all of the Electronic do-dads that it takes to power and control everything! All that is missing is the laptop computer that is usually connected to automate the controls.