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blueskies123_89
02-09-2009, 02:36 PM
Hi,

I am looking to buy a new mount for astrophotography purposes.
The setup is the following
SN8 10kg
Orion ED80, 2.5kg
Canon 400D, 0.5kg
DSI, 0.2kg
Adds up to ~14kg.

Currently all that is sitting on a LXD75 mount, it is hard to get good results.

So, ive been looking around for a new used mount - what should I get?
The options I've considered:
EQ6, would that be able to carry that load?
Wait for a while, save up for a used G11.

I know they are at two price ranges, so I really need opinions. Also, what should I be on the lookout for for 2nd hand mounts?

Thanks lots,
George

[1ponders]
02-09-2009, 02:44 PM
don't forget to add in the weight of rings, mounting bars, finderscopes, coma correctors, focal reducers, cables (particularly cable drag. ) etc etc. They all add up eventually.

EQ6 would carry it np at all.

blueskies123_89
03-09-2009, 12:57 AM
Thanks Paul.
Do old mounts still work fine? or should I really be looking for new ones.

gbeal
03-09-2009, 05:24 AM
Nah, as long as the "old mount" isn't completely flogged out, then used is good. I do it all the time, although the CGE I have now was new.
Gary

Moon
03-09-2009, 09:40 AM
Things do go wrong with mounts, with the electronics and the mechanical stuff. Before buying, I would perfer to see some evidence that the mount tracks well - for example some pictures taken with the mount (unless of course it's still in the box and has never been used :thumbsup:)

For me it's also important to stay main stream. If something does go wrong, spare parts and repairs are easier (and cheaper) to come by.

pmrid
03-09-2009, 09:57 AM
Hi George. An EQ6 would handle that lot well enough. As a rough rule, the EQ6 has a capacity of 25kg but keeping the actualk load down to 2/3 to 3/4 would be good policy. The EQ6 tracks a lot better. It has a worm gear with about 50% more teeth than the usual 144 found in mounts like the LDX75, CG5 and the like and the motors also operate with a higher number of steps all of wich transpates into higher pointing accuracy.
The EQ6 also has a built-in ST4 port so your guide cam can talk direct to it (if it can). But more than that, the EQ6 works really well in pulse0guide mode with ASCOM and EQMOD. I control mine using a gamepad wirelessly. You can actually throw the Hand Control into the bottom drawer and leave it there.
It is possible to significantly im prove the performamnce of an LXD75 though. You could, for example, install a Warpsdrive kit that will take out a high proportion of the periodic errors in herent in the geared system Meade uses. I have both an EQ6 and an LXD75 and while I prefer the EQ6 for its capacity and features, I have been able to get the LXD75 to run quite well and image acceptably.
Peter

blueskies123_89
03-09-2009, 10:18 AM
thanks guys, that really helps

bmitchell82
03-09-2009, 03:09 PM
to me the EQ6 is almost bulletproof. unless your setup isn't balanced theres not much else that can go skewifff.

blueskies123_89
03-09-2009, 11:01 PM
Thanks guys.

Jus asking for opinions, say I can get a old EQ6 syntrek >4yrs old, with eqmod gamepads, for 1250. Or i can get a new EQ6 standard (without synscan) for 1400 (from U-shop), and put on eqmod myself, which would you go for? Is it worth it to get a new one as it isn't that much more expensive

pmrid
04-09-2009, 03:54 AM
$1250 is a good price for an EQ6 with the full Monty EQMOD rig. That should include the EQDIR dongle and an RS232 cable back to the PC (or a USB-RS232 cable). The wildcard remains the condition of the mount.
At 1400, a bare EQ6 is pretty good also but I'm not sure what the SYnscan add-on entails. If it is just the hand controller, and nothing more, then the mount should be EQMOD capable as-is. Assuming that to be right, then 1400 is a good price for a new mount and all you would need to get the set up your own EQMOD is an EQDIR dongle from Shoestring (or a local equivalent) and the cabling back to your PC/Laptop. Those are cheap. The EQDIR from Shoestring is about US$35-40. That would certainly take out any uncertainty about buying second-hand.
Peter

bmitchell82
04-09-2009, 01:17 PM
You will more than likely find that the one from "U-shop" will be just the basic eq6 with just motors for tracking. the Synscan does add a few differnt features such as the guide port and the ability to read and send pulses.

i guess the easiest way to figure out if the mount will be able to go the EQMOD way is if it has the DB9/RS232 port is look at the side of the mount if you see it there, then happy days, it will accept it.

To be honest there is minimal occasions i actually utilize the hand controller mainly i belive that is due to my astro photography ways. if i was just going to set up to show people. the hand controller would be what i use, it is accurate and easy to setup. and i like this flexibility

Eqmod is the best thing since sliced bread when you want to control your telescope from the computer, there is a bit of alearning curve to overcome but overcomable! the benifits to EQmod - Pulse guiding - Improved pointing and slewing - use of wireless controls.

At 1250 if you can look at the mount things to look for.

-Backlash - grab the mount head see how much it moves on both axis
-noises - if it starts a slew and its just quiet aka you can hear the motors spinning up but no rattles/clunks shes all in reasonable shape

if you have the chance to open it up (4 phillips head screws) try and look at the gear mesh and analyse it.

Good luck and if you hvae any questions let me know:thumbsup: