Setup Questions

[Herzy]

Alright I'm seriously debating purchasing an Advanced VX mount. I already have a 5" aperture scope that is around 10lbs, a 1lb Nikon D3200 camera, and I want to get an auto-guider and auto-guider scope soon after. I assume the final weight will be around 15lbs - half the maximum payload of the AVX mount. The AVX is notorious for having motor drive failures and the culprit is most likely setups that are too heavy. Anyways, I'm basically asking what results i can expect and what accessories I should get to make my setup better. If my 5" scope (10lbs) is too heavy, I also have a 3.5" MAK that is 6.7lbs. However the focal length for the MAK is unfortunately 1250mm rather than the 1000mm of the 5".

Thanks, and please suggest some auto-guider options that I can take a look at!

-Herzy

[Nejim]

You can get a focal reducer

[wuthton]

woops, misread.

[SonnyE]

On 3/5/2016 at 16:22, Herzy said:

Alright I'm seriously debating purchasing an Advanced VX mount. I already have a 5" aperture scope that is around 10lbs, a 1lb Nikon D3200 camera, and I want to get an auto-guider and auto-guider scope soon after. I assume the final weight will be around 15lbs - half the maximum payload of the AVX mount. The AVX is notorious for having motor drive failures and the culprit is most likely setups that are too heavy. Anyways, I'm basically asking what results i can expect and what accessories I should get to make my setup better. If my 5" scope (10lbs) is too heavy, I also have a 3.5" MAK that is 6.7lbs. However the focal length for the MAK is unfortunately 1250mm rather than the 1000mm of the 5".

Thanks, and please suggest some auto-guider options that I can take a look at!

-Herzy

The motor drive failures are due to the move to China, and using China's questionable quality components in the boards.

It lends to making sure you get a warranty (the warranty is non-transferable), and I recommend the mount only be powered with a battery source, based on my experiance.

The AVX is rated for up to a 30 pound payload. I have friends who are up to 28 pounds and no problems. My refractor and all is a bounding baby boy at ~13 pounds. (Telescope, Guide scope & Camera, Imaging flip mirror, eyepiece, et al)

As a rule of thumb, usually it is sound advice to have your payload at 1/2 the rated weight. ~15 pounds. But I know of several who push the payload to near the top figure.

When in doubt, browse the Celestron website for the combinations they sell with the AVX as the mount. Including this monster. ;^)

(I'd suggest a bib to catch any drooling.) 

[sagramore]

Can I ask what scope your 5" scope is? My biggest worry would be lots of imaging with a f/7.7 scope unless you plan to get a reducer in there as well - mostly because you will need some pretty long exposures with that focal ratio. That being said, it sounds like from a weight-perspective you should be fine!

[Herzy]

I've decided instead to get the VX6 (just the AVX mount with a 6" Newtonian for an extra 100$) http://www.amazon.com/Celestron-Advanced-VX-6-Newtonian/dp/B00AZCHF6U

It is f/5 so I don't think that's too bad. I could get a reducer if it helps by a significant amount. As you said weight is most likely not a big issue for a scope this size, so I'm good there!

[sagramore]

With a f/5 reflector like that you will likely benefit from a coma corrector (I know I do with my 5" reflector!) so take a look at one of those. It's almost the reflector equivalent of a field flattener on a refractor.

I hope you enjoy your purchase!

[Thalestris24]

Hi

I think the AVX 6" newt version only accepts 1.25" eyepieces so probably can't be fitted with a coma corrector.

Louise