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I know the stated capacity of the g11t (75lbs imaging 90lbs visual) but having this mount for a few months I think that's overrated.
I think a 16" SCT (67lbs) for planet imaging is definitely pushing it. I'm looking for some feedback from anyone who has their g11t loaded, over 70lbs.?

Gee I don’t have a 16” ….we’re they not the Meade ACF…..that thing is huge. I cannot imagine many mounts could manage it. ?I wouldn’t even think a Titan is in the range maybe one of the HGM200s is something that might manage it.?

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FWIW

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Brendan

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I know people imaging with a 70+ pound Newtonian payload on a G11G and FHD no problems.? I can't imagine the a 16" SCT would be a bad payload being a lot shorter tube with a much lower polar moment, it should be fine.? I don't think the G11GT has much more payload headroom than the G11G but it should be fine.?

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The payload weight rating and inertial moment are only two of many considerations. In this case, with a focal length a bit over 4 meters and very narrow FOV, mounting method and flexure are two more considerations that immediatly come to mind.??

The 16" Meade SCT comes on a massive dual arm fork mount. I have to start with asking why not use this as it comes??

The second question is what's your intended use??

The third question is what else are you mounting/using with it??

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The simplistic way the question is asked does not reflect the complexity of the answer.?

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The simplistic way to answer your question is,? yes,? the G11T can handle it.? The mount is not "overrated" as is typical for mounts made in China. If anything it's underrated.

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How "good" your results will be is entirely a different question. That answer depends on both technical issues and skills of the user.?

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Since neither specific technical questions or issues were asked or raised, the circumstances in which the opinion proffered are unknown and the skills of the OP are also not known,? little can be said regarding obtaining or improving the OPs results other than obtaining optimum results from a 16" SCT with a 4 meter FL is an immense challenge in all circumstances.

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Perhaps if the OP is willing to start over with specific issues or questions with the intent in solving their current challenges the responses would be more useful.?

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The level of expertise by those that participate in this group is truely humbling.

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On Fri, Oct 25, 2024 at 02:05 PM, Brian Maynard wrote:

I know the stated capacity of the g11t (75lbs imaging 90lbs visual) but having this mount for a few months I think that's overrated.
I think a 16" SCT (67lbs) for planet imaging is definitely pushing it. I'm looking for some feedback from anyone who has their g11t loaded, over 70lbs.?

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Do you already own the M16" SCT?? ?If not the classic planetary SCT for portable use is a C11 or with a second person to help load it a C14.? At some point the return in resolution vs weight vs cost tips and it seems like a C14 is just past that point.? Some of the best planetary images captured here on Earth were with C11 and C14 SCTs.? If this is a dedicated planetary imaging OTA the wider FOV corrected optics of an EdgeHD or Meade ACF are a waste of money as only the optical sweet spot is used for planetary imaging.? You could use this money to chase the best weather conditions at the highest altitude to get the best? planetary images that no amount of additional aperture can capture.? ??

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On Fri, Oct 25, 2024 at 05:05 PM, Brian Maynard wrote:

I'm looking for some feedback from anyone who has their g11t loaded, over 70lbs.?

There may be few examples because the capacity of a GEM is based on the expected distance from the RA to the Center of Mass.? Observing the 16" OTA, it requires an additional 3 inches of distance to the center mass compared to the assumed capacity distance for the G11T.? Using the typical adjustments from the RA provides a reliable estimate of how the limits change with the counterweights required at the maximum limit at the standard OTA to RA axis distance.? If standard, the declination needs four 21-pound counterweights (84 pounds) to balance 90 pounds at 14.5 inches.? This becomes 75 pounds at 17.5 inches (90 pounds * 14.5/17.5), which is the new maximum allowed for visual observation.? This increase in RA axis spacing reduces capacity by 20%, positioning the mount not at the upper recommendation for photography but at or above the limit recommended for visual use.? Actual examples of this should be rare.

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As you might expect, we cannot increase capacity by adding more counterweight due to the role of inertia.? Shifting the OTA outward to this extent, while lowering the limit, also slightly alters the inertia.? However, adding weight exacerbates the issue for the mount, which is already at its maximum recommended load (torque on the RA).

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Not sure where you got your C11 from but even the lightest carbon fiber tubed USA made NS11 GPS SCT weighs more than 40 pounds when fully dressed for visual use. Granted this included Losmandy sourced V upper and D lower dovetails, Stellarvue 50mm f/4.2 RACI finder, large 3.25" mount Moonlite 2.5" focuser, 2" Baader BBHS Sitall diagonal and long 2" TeleVue eyepieces but they are not that much heavier than other similar items.?

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Because Losmandy mounts are not commodity mounts there is no need to estimate their imaging payload capacity using old wives tails for guidance.? Like AP, Losmandy has specified the maximum imaging payload for their mounts.? These payload limits are for commonly available optical tubes and they seem to work well as imaging payload guidelines.?

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As usual there are going to be some odd payloads that may prove difficult to manage but these optics will be on the periphery of the commonly available and used optics.??

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