Orion dovetail compatible with cg5-gt mount?

[wx_dan]

Hi,

I have a cg5-gt mount and am looking into getting an orion telescope (http://www.telescope.com/catalog/product.jsp?productId=9895&gclid=COHn88my67gCFcZj7Aod-EkA6A). I was considering buying this dovetail (http://www.telescope.com/8-Orion-Dovetail-Mounting-Plate/p/7383.uts) with the telescope tube rings (http://www.telescope.com/100mm-ID-Orion-Telescope-Tube-Rings/p/7371.uts) to attach my telescope to the mount, but wasn't sure if the orion dovetail was compatible with my cg5-gt mount.

Thanks,

Dan

[Oddsocks]

Hello Dan,

Had a quick look at all your items on the Orion website, the dovetail you have chosen is compatible with the cg5-gt.

There are basically only two types of dovetail in popular use, Losmandy wide and Vixen/CG5/Skywatcher, etc, narrow.

I had to double check the 100mm rings, usually I would have thought 90mm was the right size for an 80mm scope but according to the sizing chart at Orion 100mm is the correct size for the 80ED.

Was a bit confused by the pictures of the scope as they seem to show a mounting block on the optical tube for direct attachment to a Vixen/CG5 rail so the tube rings may not be necessary?

Might be worth a double check with Orion or the dealer, unless you had a particular need for the rings then you could save a few dollars.

William.

[wx_dan]

Thanks for the response William! Now that I look at the tube rings, I'm not so sure either that they are needed... honestly, I was only getting them because I thought they were needed to attach the scope. But if they aren't needed, I won't get them.

[wx_dan]

Ok, I just chatted with some of the Orion folks (via the online help/chat they have), and they told me I would need the following to use the Orion 80ED:

100mm Tube Rings (http://www.telescope.com/100mm-ID-Orion-Telescope-Tube-Rings/p/7371.uts)

Wide universal dovetail (http://www.telescope.com/Orion-Wide-Universal-Dovetail-Plate/p/7954.uts?keyword=wide%20dovetail)

I don't know if they're pulling my leg and trying to get me to spend more money as the universal dovetail is $50 compared to the 8" one that is $20... Does anyone have any experience using the 8" dovetail on a Celestron CG5-GT? Did you have to use the tube rings as well?

[Oddsocks]

Hi Dan,

Dosen't give a lot of confidence does it?

If you measure the width of your tube mounting clamp on the CG5-GT and it opens to just over 3 inches wide then this is a "Losmandy" rail and the expensive wide universal dovetail is the one that fits.

http://www.telescope...d=wide dovetail

But according to the Celestron instruction manual for the CG5-GT it has a VIXEN/CG5 mounting clamp, this will open only to just over an inch and three quarters so your first choice of rail is the right one.

http://www.telescope...late/p/7383.uts

Double check the width of your mount clamp with a ruler then you will know for sure which one to order.

Losmandy dovetail is 3" wide.

VIXEN/CG5 dovetail is 1-3/4" wide.

I' can't say for sure about the tube rings, the instruction manual for the 80ED says it has the mounting block on the optical tube for direct attachment to a rail so I would say you don't need the rings, but possibly the design of the tube has changed since the manual was printed and the block is no longer there in which you will need the rings, can you order the tube and rail first then order the rings separately once you know for sure what is on the tube?

William.

[wx_dan]

Thanks William, the width of my mounting clamp is indeed 1-3/4". Guess they were trying to get me to spend more to meet their quota

I did read over the instruction manual for the 80ED, and the way its worded doesn't explicitly say it needs the tube rings to attach it to a telescope mount. At the same time, though, I wonder if the mounting block is just meant to be used with a tripod, while the tube rings are meant for the telescope mount. In any case, I appreciate all of the help you have offered William with this! It definitely has saved me a little bit of money!