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View Full Version here: : Dual Mount/Piggy Back Mount - refractor + 350D


iceman
11-07-2007, 05:42 PM
Hi guys

I'm after ideas on how to mount my 350D and the widefield refractor I bought, on top of my EQ6.

I ultimately want to do widefield photography with my 350D + lenses, and guide through the refractor hooked up to a ToUcam/DMK (for either manual or auto guiding).

The refractor + rings can be seen in this thread (http://www.iceinspace.com.au/forum/showthread.php?t=21584).

Should I somehow mount the 350D piggyback on top of that scope? If so, how do I mount the camera?

Should I get a side by side dovetail bar and put the camera on one and the scope on the other? If so, where do I obtain such a beast?

Appreciate any thoughts. I'm looking to get this setup soon so I can take it to BSG. I won't be taking my scope but wouldn't mind being able to do some widefield photography.

Thanks

[1ponders]
11-07-2007, 06:41 PM
Mike do you have a standard set of scope rings to fit the 80? That would be the easiest way.

See soon to be attached image.

Omaroo
11-07-2007, 06:47 PM
Mike - I'd be looking at a wide dovetail plate - like the WO Vixen-style. Mount your scope on one side and the camera on the other - side by side. With this you'd have your main dovetail at 90 degrees to how you have it now. It'd be nice to have a Losmandy camera mount, but certainly not necessary.

[1ponders]
11-07-2007, 06:48 PM
I like to use the aluminium bar for a bit of added stability. It's cheap and it's effective. Just put a Manfrotto (which I think you have.....yes?? ) on top. I also like to mount the PST on top of here as well ;)



Edit: This is if I am using my EQ3 mount. See comment below re losmandy

Dennis
11-07-2007, 08:12 PM
Hi Mike

In a limited way, I've tried both options and have come to prefer side by side mounting. I have found it is easier and more convenient to fit, adjust, balance and point the two units when in a side by side configuration, rather than piggy back.

I say 2 units as my experience has been with the C9.25 or Mewlon 180 as the main unit and the WO 80mm refractor as the guiding unit, so I haven’t tried your intended configuration of small refractor and camera/lens combo.

I used WO Saddles for the imaging OTA and WO 80mm rings for the guide scope, which is an expensive and weighty option unfortunately, although considerably cheaper than the Losmandy system.

Cheers

Dennis

ballaratdragons
11-07-2007, 08:21 PM
2 votes for side-by-side so far. But may I suggest that as your camera is probably fairly light, piggy-back it on top of the refractor. Simple, effective, and you only have to rebalance one axis if you take the camera off.

Either way will work, but as the camera will be much lighter than the refractor I recommend piggy-back. Less axis to balance too.

[1ponders]
11-07-2007, 08:24 PM
However if you have the money, as Dennis and Chris have vouched for I do like the side by side mount. which I am using right this minute. :D But for cheapability, the over under with standard rings and a length of aluminium bar with the manfrotto takes some beating.

iceman
12-07-2007, 06:37 AM
Thanks so far.

However, I don't have standard rings as you can see by the photos. So there's nothing to piggyback the camera on.

Side by side might be my best option, and i'll fit the camera tripod ball mount head onto it in some way.

Where do I find good value side by side mounting options? How much are they?

Dennis
12-07-2007, 06:52 AM
Hi Mike

I assume the EQ6 has a Vixen style dovetail?

All you need is an aluminium mounting plate, similar to this example (http://www.scopestuff.com/ss_dmp6.htm)at Scopestuff which has dimensions of 3/8" thick, 6" x 16" (9.5mm thick x 15cm x 40cm).

You can then attach a dovetail adapter to the underside of this plate; Bintel sells an Orion Dovetail Mounting Plate 08" (https://www.bintelshop.com.au/Images/Stock/6921X.jpg) for $39.00. Just make sure you can fasten the lock knob on the EQ6 that clamps the dovetail, without fouling the aluminium mounting plate.

In the good old days, I made various mounting plates from 12mm plywood to hold side-by-side cameras on my Vixen GPDX mount and this worked fine. Wood is much easier to work with and when varnished to protect it against the elements, proved stable enough for camera/lens photography. The longest focal length lens I used was 400mm and I could get 5 mins unguided. 200mm gave me 20mins unguided. All 35mm film of course!

Cheers

Dennis

iceman
12-07-2007, 06:58 AM
Thanks Dennis, I'll give the boys at Bintel a call today.

Omaroo
12-07-2007, 08:17 AM
Andrews: William Optics C-VP Vixen-style dovetail plate (fits EZT, Vixen, Orion, Synta, etc.) and is 9cm x 19.5cm x 3cm in dimension. $79.00

Garyh
12-07-2007, 08:40 AM
I agree with the side by side arangement. with mine, Tv on one side of the dovetail plate and a heavy duty tripod head affixed on the other side. dovetail is 14" long and made from solid aluminium machined at a local engineers for about $55..
cheers

iceman
12-07-2007, 08:55 AM
Thanks Chris and Gary, gives me a few options. Of course you don't take that extra cost into consideration when buying a bargain refractor ;)

bloodhound31
12-07-2007, 09:11 AM
Mike is something like this any good to you?

Baz.

http://www.aussiepeople.com.au/asignobservatory/PiggybackMount.aspx