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Nikolas
25-03-2013, 09:39 AM
I see it a lot.
A mount is rated to say a payload of 15 kg, Does that include the included balancing weight? If you add a further balancing weight is that included in the payload?
eg a cg5gt is rated to 15 kg payload or thereabouts. The balancing weight is 10 kg and if you add another 5 it goes up to 15 kg.
Add a telescope with guider and camera and it could weigh 14 kg for the rig and the 15 kg for balance. which makes it well balanced. What is the payload etc?
I'm a touch confused.

Merlin66
25-03-2013, 11:39 AM
The payload of a mount is the weight of the telescope and accessories it should be able to handle.
The counterweights are on the opposite side (to balance things) and are not included in the payload figure.

Nikolas
25-03-2013, 12:22 PM
ok thanks for clarifying.
:)

RickS
25-03-2013, 12:34 PM
With most high quality (typically this means expensive!) mounts the payload number in the specs will be conservative and you may even be able to exceed it for imaging, especially if your scope is compact.

With lower quality/cost mounts you may find that tracking performance is OK for visual use but inadequate for imaging unless you stay well below the quoted maximum payload.

Just something to be aware of... It's good to get feedback from owners of the mount you're looking at.

Cheers,
Rick.

ZeroID
27-03-2013, 06:50 AM
Recommended limits for imaging are no more than about 75% of rated payload IIRC. Balance does make a huge difference but I'd still be doing my damndest to keep the rig as light as possible. It also affects vibration and dampening remember.

Logieberra
29-03-2013, 02:10 AM
A mate is considering the metal tube GSO 12" RC for his Skywatcher NEQ6 Pro. I'd appreciate a few comments here, as I am attempting to convince him that it will overload that mount. Yes, planetary and visual with a 12" newt is possible on EQ6, but surely not long guided exposures. The RC is even heavier again, am I right? Happy to be proven wrong here. Cheers.

naskies
29-03-2013, 01:15 PM
I have a GSO RC8 (carbon fibre version) on my EQ6 and find that tracking isn't perfect because the periodic error curve is a bit too jagged. I didn't notice it with my DSLR with the blooming, but it's very noticeable with my CCD. It's quite common among full resolution EQ6/RC8 images I see posted online. (The scaled down versions look great though.)

I think shooting long exposures with a metal RC12 on an EQ6 is going to be frustrating; probably futile. I find that tracking accuracy degrades noticeably even with just a DSLR piggybacked on my RC8.

Perhaps it's worth getting your mate to think about what happens if the RC12 does in fact overload the mount. If it's a new RC12, then they'll take a big hit to resell it. The next step up from an EQ6 is quite expensive, so mount upgrading will be costly. Adaptive optics might work, but they can be very expensive too. If it's a second hand RC12, then there might not be too much harm in trying, and moving it on if it's not acceptable.

Logieberra
29-03-2013, 02:30 PM
Dave, thanks for taking the time to share. I will pass this on. When I raised the question of running RC12 on G11 some time ago I got shot down fast. An expensive mismatch on a NEQ6 Pro imho...