Here is the place to talk about all those equipment(Telescope, Mounts, Eyepieces, etc...) you have. Not sure which scope/eyepiece is best for you? Trash it out here!
firstly, any idea where i can get a pier for a vixen GP mount and how much it'll cost?
secondly, any idea if this set of motor drives : http://www.optcorp.com/product.aspx?pid ... -209-11306 will fit the vixen GP mount? are the GP mounts the same as the SP mounts? cause i was thinking if the synscan can fit the skyview pros which are essentially clones of the CG5, and mooey has fitted the synscan to his SP, which are the older generation of the GP, maybe this set of motors drives from celestron will be able to fit the GP mounts...since mooey fitted a drive meant for the skyview pro (aka CG5) to his SP (aka GP)...hmm..logical deduction???
thirdly, anyone using the LXD75 in SG? if there are, pls pls do provide me with some feedback on those mounts! thank you!!!!!!
1.It is ok for a SN-6 or 4 inch refractor. Not for SN 10 or AR5,6 etc.
2.Do not expect it to be 100 % perfect out of box. It will require some checking/tightening of fixing screws of motors worm shaft etc.
3. You will have to fix an additional grub screw on the boss of drive gears , other wise the gear will slip on the shaft sooner or later especially, the RA gear.
4. The plastic covers for the motors are badly designed. .At our Latitude, some interference while slewing can be expected , unless you are careful.
firstly, any idea where i can get a pier for a vixen GP mount and how much it'll cost?
You mean full pier or half-pier?? I think someone is selling a full pier quite sometime ago... you need to check the buy and sell. Also, I think Vixen half-pier will cost around S$150 to S$200... you can check with Robin.
secondly, any idea if this set of motor drives : http://www.optcorp.com/product.aspx?pid ... -209-11306 will fit the vixen GP mount? are the GP mounts the same as the SP mounts? cause i was thinking if the synscan can fit the skyview pros which are essentially clones of the CG5, and mooey has fitted the synscan to his SP, which are the older generation of the GP, maybe this set of motors drives from celestron will be able to fit the GP mounts...since mooey fitted a drive meant for the skyview pro (aka CG5) to his SP (aka GP)...hmm..logical deduction???
Should be able to fit as someone already install and use the Sky-Watcher dual axis motor drive on GP mount successfully which is basically same as the celestron motor drive.
Have a nice day.
Yang Weixing "The universe is composed mainly of hydrogen and ignorance."
starbook S la, robin was selling 1.2k. if got budget go for the real thing mah. lesser stuff to struggle with. got more budget go for the ss2k, astro scientific got a set, 2.4k sgd nia :x
gp2 and gp basically the same, i think only change is the motor covers. nice blue colour. there's a big change btw sp and gp. the worm looks different from the outside. setting circle and length of ra axis oso different.
optron like still very infancy leh, no real reviews of it. do tell me if u have luck with it. synscan on the other hand has a large user base. lots of people playing with the eq-6. eqmod is quite well developed. quality of motor is oso quite gd, much quieter than the meade and celestron. of course, like i mention earlier, if got budget, or got the luck, ss2k still the ultimate.
anyway, the synscan fits for me after some minor mod(6cm m5 screw since sp mount ra axis is longer), it doesn't mean it confirm will fit every gp mount wor. there's may be some risk and figuring involved. dun later jump on me say cannot fit hor. i innocent one. but if u need any help, feel free to call me.
Yes. I do a research on it and seem quite good from the yahoo user group... only problem is that the ASCOM driver doesn't work properly from the last time I check. I initially also plan to get one, but figure out I would prefer a "push to"... hope that someone will come out a neat DSC for Vixen GP mount.
This of couse will work la... it for GP mount ma... You can check with Robin on the price. This is the more safe option compare to the Nova GOTO kit.
By the way, the motors are included for the Nova GOTO upgrade kit and Vixen StarBook S... the motors are different from those use by the dual motor drive.
Have a nice day.
Yang Weixing "The universe is composed mainly of hydrogen and ignorance."
yes, motors provided by the cg5 dual drive kit and the motors provided by those in goto kits are vastly different. there are usually 2 different kind of motors, servos and steppers.
the vixen mt-1 motors are steppers. most china dual axis drives are dc. synscan uses steppers too, but these are capable of 1/64 microsteps. thus allowing much lower gear reduction ratio and higher slew speeds than normal non goto steppers.
lxd75 and the celestron asgt are using servos. it works by putting an encoder in the motor. typically they have lesser torque, but makes up for the difference by having a high reduction ratio and high rpm.
Here are some thoughts about the Vixen GEM mounts:
Whether it is an SP/SPD/GP/GPD/GP2/GPD2 variant, both the DEC and RA axes can be adjusted until it is close to perfect. However, do this only if you feel comfortable taking apart the mount (partially) or let someone else more experienced do it for you. And again, regardless of the mount variants listed above, one has to take care (in particular) the mount head. I have seen these Vixen mounts transported (naked), with no storage bags, or whatsoever, and they are consistently knocked around in the transporting vehicle (as it goes through humps, and undulating road during expedition trips. You should never allow your poor mount to go through this undue torture. Why? This will worsen the periodic error of the mount over time. Note that both the worms and gears are made of brass and if you knock the mount hard enough, with the RA or/and DEC axes in their locked positions, the worm will get the force of impact against the gear. As brass is a soft metal, it will bend the worm splines. You just need a couple of microns of 'damage' to worsen the mount's inherent periodic error. If you have a SP/SPD mount, or even an old GP/GPD(2), you could improve your periodic error performance by installing new (unworn) worms. You should get around 10-16 arc seconds normally, but I have seen a GPD that has something closer to 8". These are generally decent and good mounts, and especially more so if you get them in the second hand market. The periodic error profile of these mounts are have generally gentle diffential errors rather than errors coming in spurts when one evaluates the PE profile. This would spell good news since it would be easy to autoguide out errors when retrofitting with kits that enable autoguiding. Another way to further improve the performance of the periodic error would be to do regreasing. This will not lower the periodic error, but further make the periodic error performance more gently changing. Another important point once you get the motors, you have to make sure that the gears are always flushed with each other (the one connected to the motor itself, to the one that is connected on the mount gear axes). The meshing should not be too tight, otherwise this will wear the gear and damage the mount. One rule of thumb is to be able to put a small piece of paper through the teeth. This will give you an idea of the ideal separation distance of the gears.
As for motor retrofitting, you could try getting the "traditional" DD2 controller system for the mount (assuming it is Vixen), together with MT1 motors (and they are backward compatible to SP/SPD mounts now), or go with the monochrome LCD display-based STARBOOK S GOTO kit. If you have a tight budget, you can try putting LXD55/75 motors on it. Full goto retrofit with Meade Autostar capability will set you back about $200-450 american dollars (which is low now). Installation is not difficult (requiring two screws and some adjustments and maybe shimming to optimize the spur gear mesh on both axes). And as you are probably aware, you could consult Mooey on his Synscan retrofit experience onto the SP mount.
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"The universe is composed mainly of hydrogen and ignorance." 
