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JMI MiniMax

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#1 Joe Cepleur

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Posted 12 March 2013 - 08:18 PM

I respected source has advised me to add a JMI MiniMax to my orange tube C8. I know what digital setting circles are in general, but have never used them (or, to be honest, even seen them). I could get the system complete with encoders and all hardware for $275.

It has been hard to get information about this on the Web. I suspect it is an older system. Perhaps someone here could help? Any ideas about price? performance? reliability? Maybe post pictures?

How much of a revelation would this be over using just the C8's built-in mechanical setting circles and a wide-angle eyepiece?

#2 Billydee

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Posted 12 March 2013 - 08:38 PM

Joe,

Google "JMI G-11 encoders". He is still in business JMI = Jim's Moble Inc. You will get enough reading material and a phone listing for the company.

Bill

#3 Joe Cepleur

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Posted 12 March 2013 - 09:08 PM

Yes; lots of pages referring to JMI encoders for the Losmandy G-11 mount. You're saying the same beast, or one similar, will also fit my C8?

#4 Falcon-

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Posted 13 March 2013 - 02:04 AM

I have the JMI NGC-MAX - I use it on a Celestron CI-700 mount.

I suspect it is an older system.


Yes, the NGC-miniMAX seems to have been replaced with the NGC-microMAX. Looking at the NGC system manual (covers the MAX, miniMAX and microMAX) it seems the miniMAX is actually more capable then the microMAX - nearly as much as the full sized NGC-MAX (but lacking the IDENTIFY command and with a smaller screen).

Check out page 13 (Appendix A) of this manual: http://www.optcorp.c.../max_manual.pdf


There is of course a second way to answer that question. Yes, having first used the Nexstar system on my CG-5 before I got my hands on the NGC-MAX yes it *feels* like an older less sophisticated system.

Perhaps someone here could help? Any ideas about price?



Price is easy, check out JMI's web page for all the various versions as well as the encoders needed. http://www.jmitelesc...com/buy_ngc.htm

performance?


Again, having been used to the Celestron Nexstar go-to system with it's *amazingly* good go-to performance I was a bit spoiled but I found the performance to be simply adequate. Once I got the hand of doing the 2-star calibration at startup it would indeed generally place the scope at or near the target.

I admit I am trying to use the setup for photography though, so most of the time the targets I am trying to shoot are not visible to the eye and require a several-minute exposure to be sure I am on the spot, so being even slightly becomes frustrating quickly for me. I think if I was just doing visual and starting out with a wide eyepiece I would be much happier with the accuracy.

reliability?


Well mine has not broken yet. :p Worst "reliability" problem I have had is that I forgot to turn the thing off and drained the 9v battery dead by the time I went to use it the next night! (not exactly something one could blame the system for...)

How much of a revelation would this be over using just the C8's built-in mechanical setting circles and a wide-angle eyepiece?


For *me* having never mastered the fine art of star-hopping it would make a huge difference in finding smaller and fainter visual targets.

Perhaps the final thing I should say is that I hope to upgrade my CI-700 to true go-to, but instead of selling my NGC-max my plan is instead to adapt it to use on my own orange-tube C8 fork! I mostly bring out visual scopes when I want to show other people targets and having the DSC push-to will get me on those targets faster and avoid my guests loosing intrest while I hunt for that target I was SURE must be here some place..... ;)

#5 Joe Cepleur

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Posted 15 March 2013 - 06:47 PM

Thank you! The thoroughness of help found on Cloudy Nights continues to delight and astound me.

Not surprisingly, while learning about the MiniMax, this one was sold to someone else. There will be others, and I'll be ready.

It strikes me as far better than GoTo. It allows fast manual slewing whenever desired, without losing alignment. No noisy motors. No interfering with star hopping. Better durability. Retains a sense of astronomy as a tactile activity. We must be blindly in love with technology for GoTo to replace this!

#6 ASTERON

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Posted 16 March 2013 - 04:02 AM

Joe,
While not directly comparable, I have been using a DM4 with encoders and sky commander with a 4.5" refractor and the operation is simply flawless.
I can set up with two star alignment and very accurate push to in less than 3 minutes. These DSC systems are simplicity incarnate and are a pleasure to use and will enable you to triple the number of observable objects.
Get one and never look back.

#7 orion61

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Posted 24 July 2013 - 11:00 AM

I know this is an old post but I have been using MiniMax computers since the 90's, Make sure it has Ver 2.88 in it.
that has the Planets and is y2k compatable.
If I use a cross hair eyepiece when aligning, it is very accurate.
Biggest issue is you cannot get a copy of the Database for it.
another tip is have the tripod level and your scope adjusted for cone error IE set dec to 90, center Polaris and spin the forks, Polaris should stay centered. if it doesnt you optical axis is off. This makes a big deal with mechanical setting circles as well.






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