Mounting an 8" dob?

[pcool2 (Patrick)]

I am getting a HEQ5 pro mount soon and i was just wondering what dovetail Plate and rings will i need and any suggestions where i can get them from for as cheaps as possible.

Thanks

[[1ponders] (Paul)]

The tricky part Patrick will be getting rings to fit. From memory, dob diameters are slightly bigger than newts that come standard on EQ mounts. I'm not familiar with the "pro" mount, does it come with a Losmandy D type saddle or the standard narrow Vixen style saddle?


Either way you will need the suitable dovetail, a nice long one, and the appropriate rings. AND sufficient weights.

[mldee (Mike)]

8" dobs are normally f6 and 1200mm long. They tend to be a little more clumsy on an EQ mount due to their extra length.

If you are getting the HEQ5 for AP work, have you considered selling the dob, (very easy to do) and getting an f5 1000mm newt OTA and eventually a nice big-sensor CCD such as a QHY9?

I just make the comment as I went through the same experience and the f5 is just physically a better choice on the EQ mount. If you later decide you want longer FL for galaxy imaging, keep your eye out for a used GSO 8" RC. My 2c.

[pcool2 (Patrick)]

Hey mike i have considered that but im going to do that later on. But for now im going to stick with the dob. Im thinking of buying 235mm rings and a 30cm dovetail from york optical. Will this do for the dob.

cheers guys.

[mldee (Mike)]

I'm by no means an expert on this, but my experience was that it's probably a good starting point. You'l find out if you have any flexure soon enough!

My experience, although based on trying to get an SBS setup to work well, was that the Losmandy-stype wide dovetail was far superior to the narrower vixen. YMMV.

Vixens are OK for piggyback mount of a 80mm guidescope on the newt, etc, but perhaps due to more money than sense, (and I'm not at all rich ), I'd go with the wider dovetail eqpt whenever possible for scope mounts.

Start with the vixen, you can always use it later on top if you change.

As to rings, I seem to recall that the 235's worked OK with my SW 8" dob.

Cheers,

[pcool2 (Patrick)]

Hey mike thanks for all the advise. I appreciate it. Hopefully i will have my mount soon ready for mars next months.

Cheers