Orion 52083 - Manual (Page 4)

Figure 2b. If your telescope has T-threads, remove the nosepiece from the SSDSMI-
2 and thread the camera directly onto the telescope. This provides the most secure
connection.
T-threads
4
In order to reach focus, the telescope must have approximately 0.6" (15mm)
of inward focus travel relative to where a standard eyepiece focuses. If your
telescope does not have enough inward focus travel, you will need to use
and optional 1.25" barlow lens to extend the telescope’s focal plane to the
camera’s imaging plane.
For most types of astro-imaging with the SSDSMI-2 (except planetary imag-
ing), using a telescope with a focal length of under 1000mm is recommended.
Otherwise, the field of view may be too small to capture the entire deep sky
object. To decrease the effective focal length of your telescope, use a focal
reducer lens (available from Orion). If you are imaging planets, however, you
will benefit from using a telescope with a long (over 1000mm) focal length. Or
you can use a barlow lens to extend the effective focal length of your telescope
to increase planetary image scale.
Mount
An equatorial mount with right ascension motor drive is required for deep sky
imaging with the SSDSMI-2. Otherwise, objects will drift in the field of view as
the image is being captured. It is also very important that the mount tracks
very accurately with little periodic error. If not, stars will not appear round in the
final image. Use a sturdy mount that is appropriately sized for the telescope
tube being used. Accurate polar alignment will also be required.