DUP-S Comparison..Losmandy & Socal Astro Assys

[ARTICLEIMGR="1"]The photo shows DUP-S plates as sold by Losmandy (top) and Socal Astro Accessories

You will notice the two plates have a different bolt pattern. A notable difference is that Socal has larger holes that enable a heavier telescope to be mounted. If one were to follow the installation configuration such that the DUP-S is used as a mounting platform for cameras and such, some other method of "goof proofing" would need to be incorporated in the event you don't lock the DAs properly (notice the thumb screw in the Losmandy plate).

I found the Socal interface is wider (2.985) than a variety of Losmandy plates I own which range between 2.935 to 2.950. This isn't a problem (to me) as the Dovetail Adapters are adjustable over this range.

The surface smoothness shows no comparison, as the photo shows.

How you intend to use the plate will determine if these differences are a problem. Clearly, the two plates are not interchangeable with each other due to the different bolt patterns, although in form and function they are. Therefore it is important that you verify that whatever you plan on mating these plates to have the correct bolt pattern or spacing. The roughly $15 cost difference may also encourage others to try the Socal version. I'm happy with mine and plan on installing it in such a way that no one would notice the surface roughness.

Tom
Tucson, AZ

Click here for more about the Losmandy DUP-S. -Ed.