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View Full Version here: : Guiding on a budget (Advise Please)


Nico13
31-07-2010, 08:59 PM
Hi all,

Well here I am still slowly setting up with the eventual aim of doing some photography.

What I think I need is and auto guider and some improved or better quality drive motors that will work with an early Auto Star Goto system.
The current Meade motors while working as a drive will commonly give a motor fault error when trying to slew a long way.

Not having a large budget to work with I'm looking for advice on some updated parts to use with what I already have and an auto guider that will also fit the system.

I have no problems in making parts to adapt things to fit as I have the necessary tools and machinery and don't mind doing electronics mods I'm also quite happy with computer interfacing.

My system as it stands today is as follows.

OTA is an early Meade 8" SCT age unknown but in very good condition.
I had been told when I bought it that it was twenty five years old, after looking at it I think it sat under someone's bed for at least half that time if it's true as the condition belies it's age.

Recently added a focuser and a 2x 2" barlow

Mount is a Vixen Super Polaris EQ also in fairly good condition.

Drive system is a Meade Auto Star adapted to fit the Polaris mount.

This is all on top of a movable pier that I built as the above kit of bits previous owner had it on a concrete pier.

So the guidance I need (excuse the pun) is how to guide this on a budget and what if any motors would work with the Meade system and improve the drive.
Is it worth spending a few dollars on?

Any help would be grateful. :)


Nico.

TrevorW
01-08-2010, 01:22 PM
Neat setup Ken and if you plan to get into astrophotography then I'd start saving

guiding isn't crucial if you have good tracking and spot on polar alignment you can get subs up to 3 minutes easily

however I recently saw a QHY5 advertised for $250 and as far as guiding goes these and the Orion SSAG (basically a QHY5) camera's using PHD are the cheapest and simplest to use that I am aware of

this attached to a good finder even a focusable 10X50 will provided guiding on a bright star but I don't believe your mount comes with a guide port and to modify it to do so is another expense

Nico13
01-08-2010, 07:18 PM
Thanks for the reply Trevor,

Yeh not realy sure what was needed to do the job and more so what will work with what.

I was wondering about it all connecting together and compatibility etc so will just have to do a bit more research as to what's available.

The junction box for the drive motors and hand peice does have a Aux input, is that the port needed for guiding control plugin?

Nico.

tlgerdes
01-08-2010, 09:00 PM
Hi Nico,

As the "Other":eyepop:Trevor said, the Autostar doesnt have direct guide ability.

You can though still autoguide, but you need a computer to act as the mediator. The Autostar AUX port is an RS232 port that accepts LX200 commands. You can google for the pin outs.

You can use something like PHD Guiding as the PC software to accept the picture from a supported camera and then send LX200 guide commands via your computers serial port to the Autostar handcontroller.

multiweb
01-08-2010, 09:57 PM
GSO 9x50 Finder $70.00 + QHY5 $250.00 + PHD (free). That should sort all your guiding needs for a long while.

Nico13
02-08-2010, 01:51 PM
Thanks guys,
A couple of different options here for me to look at.

I have to sort the motor fault when slewing but that's not a problem if I'm not using the goto and just using it as a drive system.
I have managed reasonable tracking with good alignment but I may be asking too much of the drive and mount with the all up weight.
Just need to balance it well I guess, stripped one set of motor drive gears when I forgot to set the counter weights.

I need to look at the big picture and put the whole lot into context to see where the week points are and work from there.

I'm not in a great rush to do this so will take my time and sort through it.

Thanks again for the tips and a few thing for me to look at. :)

Nico.

dugnsuz
02-08-2010, 02:16 PM
Errrr...
http://www.iceinspace.com.au/forum/showthread.php?t=64212
(shameless self promotion, sorry!)
Doug

Nico13
04-08-2010, 01:25 PM
Been looking at PHD Guiding and it looks to be what I need at the right price.

Only problem I see is the connectivity of it all so need a little more advice here if you can help.

The Shoestring GPUSB interface requires a 6 pin socket and my older Autostar junction box only has an 8 pin for the hand piece and a 4 pin Aux port. See the picie attached.

Any ideas, anyone come accross this before and found a solution??? :question:

telemarker
04-08-2010, 02:05 PM
To connect a GPUSB to the mount you need the Meade 909 auxiliary module, which is about as common as rocking horse pooh these days but a clone is available. The cheapest and easiest method is to use a 506 serial cable between the PC and the handbox but the GPUSB gives better pulse guiding. Don't connect the PC or the GPUSB straight to the Aux port.

Nico13
04-08-2010, 02:11 PM
Thanks mate a very handy bit of info, I've just nabbed a GPUSB off the clasifieds so will have to chase the 909 module now.

Nico.

telemarker
04-08-2010, 02:16 PM
Chances are you won't find a 909, Meade stopped making them some time ago. I've a 909 clone and it works perfectly with PhD and a GPUSB. Google should find it.

telemarker
04-08-2010, 02:19 PM
Clones can be found here:

http://www.astrogene1000.com/products/as_909/as_909_clone.htm

hotspur
05-08-2010, 06:39 PM
Been reading this thread,And am also interested in auto guide bit.

I have a Vixen SS2K on GP mount,I want to keep the weight to a minimum

Marc,mentions a 7 by finder scope-How do you attach camera part to it?

Anyone with any pics of this budget set up??

I notice a few 'Orion pro shoot-auto guiders' popping up for $300 second hand,

Also Notice a MKII version for $495 that has LPI,so I could afford one of them in the future.

thanks for any advice,C

tlgerdes
06-08-2010, 09:31 PM
Here is a link to info on making a serial cable to connect to the AUX port of your Autostar 497.

With this cable you can then guide from PHD, (you will also need a serial port on your PC)

http://www.weasner.com/etx/autostar/as_cable505.html

So it goes like this.

Camera -> PC with PHD -> Serial Port -> Above Cable -> Autostar

Camera captures picture, PHD follows star, PHD issues LX200 guide commands through serial port to Autostar.

You have to connect the cable/computer/autostar up before turning on autostar. Autostar only looks for AUX connection on bootup (looks for electrical signals).

Shiraz
06-08-2010, 11:42 PM
Hi Ken

Nice system, but a note of caution - your scope has a 2m focal length and your class of mount is highly unlikley to guide/image properly at that focal length unless you add an adaptive optics unit. Even with a 6.3 reducer, I would think that you will have trouble. Maybe someone out there with SCT or Vixen mount experience could comment?

If you want to get into imaging with your existing system, why not just get a QHY5 camera or similar and use it for solar system imaging, where you don't need pixel level guiding - your scope/mount/Barlow would be fine for producing good quality images of the moon and larger planets without any further additions/modifications. Then, if you want to get into DSO imaging with a heavier mount and/or possibly a shorter focal length scope, you will be able to use the QHY5 as a guider. Also, your mount may just possibly be suitable for guiding with a shorter, lighter scope.

Sorry to be so negative, but my experience has been that good quality long period guiding is pretty difficult without a good quality, lightly loaded mount.

Nico13
07-08-2010, 07:56 PM
Thanks Trevor and Ray.

Trevor, that lead looks good unfortunately I've just picked up a GPUSB adaptor from the forum here to use with PHD guiding software, it was fifty bucks so not too bad as they are over 100 new.

I then found out I needed another adaptor, :screwy: a 909 to go from GPUSB 6 pin output to the 4 pin Meade Autostar Aux input.
Meade no longer makes them :question: but a clone is available, another fifty bucks from the US.

I already have a suitable webcam to use with PHD it tested well.
So already spent the money for all the bits I need but it would be interesting to make up the other lead as I do have a USB to serial adaptor, no serial on the laptop. (seems this world runs on adaptors) :help:

Ray,
Thanks for the input and advice. As the seriousness hasn't set in yet it will be interesting to see what I get with this setup and at this stage it's all been sanctioned by the finance department but it's a bit like any hobby/passtime we choose.

Photography is an integral part of this and so your camera is never good enough or your computer isn't fast enough.
I unfortunately also fly Radio Control Helicopters and of course they are never big enough or fast enough.

It all boils down to the wallet not being full enough. :eyepop:

Oh well there's always lotto tonight. :thumbsup:

Thanks all, will report back when it's all up and running.

Nico.

Nico13
07-08-2010, 08:21 PM
You wouldn't credit this, I was just going through my box of bits and guess what I found in the bottom, the exact lead you have refered to here in the link below. :rolleyes:

Turns out when I first bought the scope and mount I did a bit of hunting around and found this info so I made up the lead thinking it could be used for a firmware update on Autostar.
Put it to one side and forgot about it, so guess what I'm going to be doing tomorrow. Got everything I need to try it out.

Nico. :thanx:

telemarker
09-08-2010, 09:38 AM
Well.... How'd it go?

Nico13
09-08-2010, 10:14 PM
Sorry Keith a few other things popped up so I should get a go at tomorrow as I have the day off.

Will get back after I give it a try.
As I don't have a camera setup fully I will be using the test mode in PHD, at least I think I should be able to test it that way.

Ken.

Nico13
10-08-2010, 03:42 PM
Sorry Keith, cant test it as yet, turns out the std connectoer is too wide to fit the 4 pin socket on the Aux input so will have to chase up one to fit before I go any further.

Ken

Nico13
12-08-2010, 08:50 PM
No go with the direct serial connections, the software didn't want to know.Possibly some other software may do the job but as the parts I've purchased have started to turn up I'm not going to bother persisting with the serial side of things and just wait for the 909 clone to go with the GPUSB and just run with the PHD guiding software.

The supplier of the 909 clone has said I may still have issues with the 497's firmware level and may need to flash it to a later version.

For some reason the 497 hand peice I have appears to have a French firmware in it and as that's what it had when purchased second hand I have no idea of its origins. it's got V33f4 so I'm guessing the f is the French designation, don't know?

Will report back later.

Ken.