Astro Engineering Coll-U-Mates

Astro Engineering Coll-U-Mates

In any telescopic optical system, alignment of the optics is critical in producing a sharp, crisp image.  In order to produce this sharp, crisp image, you need the ability to move the optical components to allow the user to correct the light path.  In a Schmidt Cassegrain system, the secondary mirror is set on three adjustable points to compensate for any irregularities in the primary mirror.

Astro Engineering Coll-U-Mates are replacements for the stock hex key screws in the secondary housing.  There are several manufacturers of this type of accessory, but the Coll-U-Mates are noticeably different. These collimation knobs are larger than other models that I've seen.  This is not necessarily a bad thing, but I was concerned about the possibility that the knobs would get in the way of the corrector plate cover.  As it would turn out, my concern was not founded, and the front cover plate easily fit over the collimation knobs.

Replacement of the hex key machine screws of the stock secondary housing is relatively painless, however, you must make sure that you do several things to keep you from doing damage to your scope if things should go wrong.  You must rotate the OTA so that the secondary housing and corrector plate are tilted slightly towards the ground.  This keeps the secondary mirror from accidentally falling into the OTA and damaging the primary mirror.  Using your hex key, you slightly loosen each of the hex key machine screws, and then take one of the machine screws out.  Take one Coll-U-Mate replacement screw, place the small plastic washer over the screw, then gently start threading replacement into the secondary housing.  Once you feel a tightening, stop with that screw and proceed to the next, doing the same procedure.  These must be done one at a time.  There is no exception to this rule.  Once all three Coll-U-Mate replacement screws have been mounted on the secondary housing, you can proceed with the normal collimation procedures.

These Coll-U-Mate replacement screws are a real plus to any Meade SCT owner.  Besides making it easier to collimate your SCT, it keeps you from getting your hex key dangerously close to your corrector lens.  This alone makes it well worth the minimal cost to add this to your SCT.  Every SCT owner should have a set of these collimation screws on their scope. I did not have an opportunity to try these on an f6.3 scope, but the set of Coll-U-Mate screws that I received state that they are for an f10 scope. If you have a f6.3 scope, you may want to tell the fine people before you place your order.

Mike Overacker

Product is available from Astro Engineering