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Meade LX-50 EMC 10"

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#1 Clumpybug

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Posted 19 September 2013 - 08:24 PM

Howdy folks,

Found a 10" LX-50 for about $750, including the mount. Is this a good price? Right now I have a 8" LXD75 Newtonian, but I don't know much about CS scopes. I'd like to use it with my Canon T3 for astrophotography. What do you think?

Thanks!

#2 orlyandico

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Posted 19 September 2013 - 09:07 PM

That is a good price, but it is f/10. Hence astrophotography is going to be really difficult due to the slow focal ratio and long focal length.

#3 Clumpybug

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Posted 19 September 2013 - 11:07 PM

Really? Hmmm. How do people do AP of small objects? Just really expensive cameras and autoguiders?

#4 SeattleScott

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Posted 19 September 2013 - 11:15 PM

The camera has nothing to do with focal ratio. If you want to take pictures with a SCT other than the moon and planets, you need a focal reducer.

#5 orlyandico

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Posted 19 September 2013 - 11:23 PM

1) if you want to take pictures with an SCT, you need a corrector, not necessarily a reducer. But most SCT correctors are also modest reducers. The 6.3 reducers are mediocre at best, so you would be looking at something like the ASA or Starizona reducers, which aren't cheap. Alternatively, you could use a refractor reducer, which work surprisingly better than the 6.3 SCT reducers and don't cost much more.

2) people do AP of small objects with a long focal length like an SCT or RC - but they use very good mounts to meet the stability requirements of the long focal length and long exposures forced by the slow focal ratio. That LX-50 fork mount is the exact opposite of "very good mount."

http://uncle-rods.bl...d-and-ugly.html

Warts? The LX50 had plenty. To begin, it “featured” aluminum drive gears which tended to land astrophotographers in PE hell. Meade soon replaced the initial components with better ones, but the bloom was off the rose by then.


Successful AP is much more about the mount than the scope or camera.

Translation.. if you want to do AP of deep sky objects with an SCT, particularly the heavy Meade SCT (which weighs more than the Celestron equivalent), prepare to spend at least 5 grand on the mount if you don't want blurry and trailed images.

#6 Clumpybug

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Posted 19 September 2013 - 11:52 PM

Interesting. . . even with an autoguider, I'd end up with blurry images?

#7 orlyandico

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Posted 20 September 2013 - 01:10 AM

Yes. An autoguider can't compensate for substandard gears, slop in the mechanicals, unresponsive motors, backlash, etc. etc. etc. But you should already know that, given your problems autoguiding your LXD75...?

The thing is short exposures might work on that mount, but the SCT is so long (2500mm focal length) that all errors would be magnified. And it's so slow (f/10) that you'd need very long exposures.

This is why Astro-Physics and Software Bisque remain in business, unlike Meade which has been bought out by the Chinese. Mechanical precision costs money, and precision is needed that people will pay the money to get it.

Bottom line, imaging with an SCT, particularly a heavy one like the Meade 10" is going to be a challenge unless you have a very good mount.

That said $750 is not a bad price. You could defork it, sell off the fork mount, and apply the proceeds to a better mount. You could also sell off your LXD75 while you're at it. Between the fork and the LXD75 you're halfway to a used Atlas.

I know someone local who uses a Meade 10" on an Atlas. Results are.. not too bad. I wouldn't want to do it though, but it is possible.

#8 Clumpybug

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Posted 20 September 2013 - 11:07 AM

Cool, thanks for the info! Oorlyandico, you're quite perceptive! I do indeed have guiding problems with my LXD75, I think b/c of some nasty backlash. If I'm likely to have the same problems with any cheapish mount, then no reason to get another cheapish mount.






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