Jump to content


Photo

goto options for non-Gemini G11

  • Please log in to reply
14 replies to this topic

#1 10KL

10KL

    Vostok 1

  • ****-
  • Posts: 127
  • Joined: 10 Nov 2005

Posted 11 March 2011 - 09:28 PM

I performed some quick Google searches on this topic but only got results involving argo navis or servocat. is it possible to use only a laptop (with appropriate software, of course) without additional hardware in order to perform goto on G11?

#2 Rossmon

Rossmon

    Messenger

  • *****
  • Posts: 404
  • Joined: 09 Jul 2010
  • Loc: Marin County, CA

Posted 11 March 2011 - 10:06 PM

I think you could buy an encoder kit. I think I've seen them for losmany mounts.still 300-500 I think but a lot cheaper than the Gemini upgrade unless u happen to find a used one. I ve seen 1 or 2 used ones but they are still pricey.

#3 D_talley

D_talley

    Vanguard

  • *****
  • Posts: 2053
  • Joined: 07 Jul 2005
  • Loc: Richmond VA

Posted 11 March 2011 - 11:06 PM

You would still need the correct motors to do the slew. The non Gemini G11 does not have them.

#4 10KL

10KL

    Vostok 1

  • ****-
  • Posts: 127
  • Joined: 10 Nov 2005

Posted 12 March 2011 - 12:49 AM

You would still need the correct motors to do the slew. The non Gemini G11 does not have them.


argh! bottom line, what is my best bang for the $ option?

#5 gnowellsct

gnowellsct

    Fly Me to the Moon

  • *****
  • Posts: 6748
  • Joined: 24 Jun 2009

Posted 12 March 2011 - 10:31 PM

You should go to the Losmandy group which is in my signature. In the LINKS section are some links to some alternative drive systems, there are several.

As a rule servo motors are preferred to the stepper motors for go-to, but there are some stepper based systems. They don't slew as fast.

regards
Greg N

#6 orlyandico

orlyandico

    Fly Me to the Moon

  • *****
  • Posts: 5448
  • Joined: 10 Aug 2009
  • Loc: Singapore

Posted 12 March 2011 - 10:40 PM

the German FS2 system will work with a stepper G11.

but it won't goto very fast unless the motors are replaced with ones that have a lower gear ratio.

trouble is with the Euro / dollar exchange rate, that FS2 isn't exactly cheap...

#7 scopeman

scopeman

    Lift Off

  • *****
  • Posts: 7
  • Joined: 17 Mar 2007
  • Loc: California

Posted 14 March 2011 - 10:02 PM

If your handy and into tinkering, check out Sidereal Tech by Dan Gray. He sells 2 servo controllers one is about 350.00 or so and the other is more costly but has a bunch of features. Of course you will still need motors and encoders but they can be had on ebay pretty cheaply. I have built two complete mounts from scratch using his cheaper controller and am very happy with the results. There on Yahoo and there is a fellow who converted his G11 to this system. Might want to check em out if your into this kind of thing.
Barry

#8 Phil Cowell

Phil Cowell

    Surveyor 1

  • *****
  • Posts: 1566
  • Joined: 24 May 2007
  • Loc: Southern Tier NY

Posted 15 March 2011 - 04:23 AM

There are quite a few folks who have gone to the SiTech. The Losmandy Servo motors can be used as well. Spare parts for the SiTech are readily available as well.

#9 Eddgie

Eddgie

    Voyager 1

  • *****
  • Posts: 12646
  • Joined: 01 Feb 2006

Posted 15 March 2011 - 08:20 AM

It is not what you asked for, but here is my advice.

Sell your current mount and replace it with a Gemini, or just upgrade to the Gemini.

Hacking together a system will probably cost you just as much as this option, and by the time you get it done, it probably will not be as integrated as the Gemini mount.

Also, if you ever resell, you may find it much easier to resell the Gemini than to sell a kit mount.

No offense against these aftermarket suppliears is intended, but sometimes, getting replacement parts or support if something goes wrong can be tedious.

If you go from Losmandy, parts and support are more assured, as is resale value.

#10 Phil Cowell

Phil Cowell

    Surveyor 1

  • *****
  • Posts: 1566
  • Joined: 24 May 2007
  • Loc: Southern Tier NY

Posted 15 March 2011 - 05:12 PM

It is not what you asked for, but here is my advice.

Sell your current mount and replace it with a Gemini, or just upgrade to the Gemini.

Hacking together a system will probably cost you just as much as this option, and by the time you get it done, it probably will not be as integrated as the Gemini mount.

Also, if you ever resell, you may find it much easier to resell the Gemini than to sell a kit mount.

No offense against these aftermarket suppliears is intended, but sometimes, getting replacement parts or support if something goes wrong can be tedious.

If you go from Losmandy, parts and support are more assured, as is resale value.


Sorry but the SiTech uses the same servo's the Gemini does, no cludge here. You can get parts for the SiTech, can't say that for the Original Gemini (why buy obsolete now tht would be tedious) so unless it's a Gemini 2 your better spending your money on a current product.

#11 10KL

10KL

    Vostok 1

  • ****-
  • Posts: 127
  • Joined: 10 Nov 2005

Posted 19 March 2011 - 12:43 AM

first off, thank you everyone for your feedback.

It is not what you asked for, but here is my advice.

Sell your current mount and replace it with a Gemini, or just upgrade to the Gemini.

Hacking together a system will probably cost you just as much as this option, and by the time you get it done, it probably will not be as integrated as the Gemini mount.

Also, if you ever resell, you may find it much easier to resell the Gemini than to sell a kit mount.

No offense against these aftermarket suppliears is intended, but sometimes, getting replacement parts or support if something goes wrong can be tedious.

If you go from Losmandy, parts and support are more assured, as is resale value.


Sorry but the SiTech uses the same servo's the Gemini does, no cludge here. You can get parts for the SiTech, can't say that for the Original Gemini (why buy obsolete now tht would be tedious) so unless it's a Gemini 2 your better spending your money on a current product.


Phil, i was hoping if you could elaborate a bit more. SiTech uses Pittman motors. are you saying that Losmandy is using Pittman brand or the exact Pittman model that SiTech uses? the reason for me asking is because SiTech motors are much larger than Losmandy's. at least according to the images found on both sites.

#12 Phil Cowell

Phil Cowell

    Surveyor 1

  • *****
  • Posts: 1566
  • Joined: 24 May 2007
  • Loc: Southern Tier NY

Posted 19 March 2011 - 05:09 AM

Phil, i was hoping if you could elaborate a bit more. SiTech uses Pittman motors. are you saying that Losmandy is using Pittman brand or the exact Pittman model that SiTech uses? the reason for me asking is because SiTech motors are much larger than Losmandy's. at least according to the images found on both sites.


I recommend you join the SiTech yahoo group. Several folks there used the servos on their Losmandy mounts with the SiTech controller. You can get advice there from folks who have done the conversion.

Phil

#13 Startraffic

Startraffic

    Viking 1

  • *****
  • Posts: 755
  • Joined: 12 Feb 2006
  • Loc: Lat. 39.143345, Long. -77.174802

Posted 26 March 2011 - 09:16 PM

10KL,
I have an older G11 non-Gemini ('92) & have just gone through what you're going through now. I had upgraded with the DSCs, motor & gear covers, & added in a Sky Commander4. I have looked at Si system, & the Fs. I also considered selling the mount as is (& it is a good one wi a PEC 2-3 before correcting :grin:) It made more sense to get the G2, GPS, 1-OPW, & Maxon motors for ~$2300 IIRC. Once I get that in & set up I'll sell off the digital drive system, DSC' cans, covers, & the Sky Commander. (I haven't quite figured out for how much yet, but it will be a while before I do anything with them folx so relax they are for sale yet.)

Star-T :cool:

#14 netwolf

netwolf

    Vostok 1

  • *****
  • Posts: 160
  • Joined: 03 Sep 2005
  • Loc: NSW, Australia

Posted 27 March 2011 - 01:33 AM

You can use gemini or maxon servo motors with sitech controller. I bought gemini motors frm another usr who upgraded to maxon motors and got the motor mounting kit from losmandy. Works with my sitech controller. Any servo motor would work but u need to mount them. Others have made or had brackets made for pittman motors. You can.also find pitmann motors frm surplus sources and some times they come up on ebay. Using gemini or maxon motors is an easier path. Suggest you join the group and see what others have setup.

Also look here
www.sitechservo.info
And here for sitech pitmann conversion
https://sites.google...o-sitech-servos

Further using hires encoder you can vastly improve mount performance.
https://sites.google...gurley-mounting

But sitech for goto needs a computer or dsc argonavis or skycommander. Some have even got it going with skyfi and ipad. If you are like me and always have a laptop then this option for control is best.

#15 netwolf

netwolf

    Vostok 1

  • *****
  • Posts: 160
  • Joined: 03 Sep 2005
  • Loc: NSW, Australia

Posted 27 March 2011 - 01:39 AM

A good stepper alternative is the littlefoot elegance photo.
elegance.photo.rajiva.de
Like fs2 this will work with the losmandy steppers but your slew speed is limited to 16x.
But this system does not need a laptop, it can operate standalone.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics