AstroTrac PS-10 Polar Scope
ITEM # PS-01-KIT
Using a very accurate mount like the AstroTrac TT320X isn't a guarantee in itself that your shots will be perfectly tracked. You need to ensure that your mount is correctly aligned with the sky, or "polar aligned" to unleash its full potential. The AstroTrac polar scope makes polar alignment a quick and easy process.The polar scope's precision glass reticule is marked for alignment with stars in the northern and southern hemisphere. In the northern hemisphere, the polar scope is aligned on Polaris and an optional additional two stars. In the southern hemisphere, the polar scope is aligned on Epsilon Hydri and an optional additional two stars in Octans - Sigma and Chi Octantis. The TT320X-AG Instruction Manual gives full details of the polar alignment procedure.
If you are shooting large, relatively bright objects, such as the Milky Way, aurorae of constellations, you don't need to polar align as precisely as you do for smaller, dimmer targets, which you would shoot with a telephoto lenses or a telescope. As a general rule, the polar scope allows you to polar align sufficiently for up to 5 minute exposures at 200 mm focal length. For longer focal lengths, it's advisable to drift align or use the TT320X-AG's built in autoguiding functionality.