No other telescope design offers the combination of features and portability as a Schmidt-Cassegrain telescope (SCT). You may not consider it the best for any one application, but it does everything pretty well. One thing it’s not so great at, though, is holding optical alignment, i.e., collimation. Good collimation is a critical step to ensure that you get the best image possible.
Until fairly recently, the best way to collimate an SCT was the star test — checking optical alignment by using a star at night. This can be a frustrating process, especially if the user is unaware of specifics that can affect the test, like poor seeing, an uncooled telescope, differences between mechanical and optical alignment, and other issues. But worst of all for me, star collimation eats into my rather limited observing time.
Wouldn’t it be nice to have an easy way to collimate an SCT during the day? Well, HOTECH has developed the Advanced CT Laser Collimator for just this purpose.
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