Serial DB9 cable to autoguide Losmandy Gemini?

[Omaroo]

Hi all

I'm a tad new to autoguiding, even newer to the Gemini, and have a question in reference to using a standard USB ToUcam on laptop with serial port running PHD or GuideDog. I want to connect the webcam to the lappy with a standard USB cable. This gives me visual star input, so all fine there. Now the only port free on my laptop is a serial DB9 port. I'd like to run autoguider software that takes the input from the USB camera and outputs guide control via the serial port to the Gemini's autoguider port.

Can it be done, or are ST-4 compatible autoguider ports and serial ports basically mutually exclusive? My guess is that they are as RS-232 is a comms standard for transmission of data, while ST-4 is probably a switch interface of some sort. The Gemini also has an RJ-12 6-pin RS-232 port. Can I talk to it using the serial port on my laptop (which is otherwise free and USB ports aren't) and use it to guide through? If planetarium software can move the mount through this port i assume that it could work for guiding?

Much obliged for any help!

[Omaroo]

It's all OK - I've just heard that Shoestring also have a parallel port to ST-4 adapter. Situation solved! There's one thing my old "field lappy" DOES have - a spare and very un-loved parallel port. This way I don't have to share my single USB port with anything or run a hub. Yay!

[JohnG]

Hi

Just remember, if you are guiding through the ST-4 Autoguiding Port, change the Gemini to Photo or All Speeds Mode otherwise nothing will happen.

Cheers

JohnG

[Omaroo]

Yep - I read that. Thanks John!

Going to give it a go tonight. One of my fellow club members (Asterisk) had a spare GPUSB cable he was willing to sell me - and he only lives a couple of suburbs away. I'll use that on my good lappie tonight and get the parallel version for my field laptop. Woohoo!

[JohnG]

Cheers Chris.

A lot of people forget that step, have fun imaging tonight, bit of cloud coming up from the South here at Coota.

Cheers

JohnG

[asterisk]

Now how does the Shoestring GPUSB connection that Jen just picked up fit into the above scenarios? Sorry - missed your later edited post

Cheers

[JohnG]

Hi Chris

Did you say you had a Serial to RS-232 cable.....if not you can get them from OPT or a couple of other places.

http://www.optcorp.com/product.aspx?pid=9166&kw=gemini&st=2

Cheers

JohnG

[Omaroo]

Excellent Geoff :) !!

I'll use the USB one for now on my tablet PC - which has far more grunt than my old IBM Thinkpad - which is the machine I eventually want to run just guiding duties on. I'll use it to guide and the Fujitsu tablet PC to do the photography via ImagesPlus. Having both the USB and parallel versions gives me the flexibility I'll want later on.

Great to have the USB now though!!! Thanks to you Geoff :thumbsup:

[asterisk]

Chris

How did last night go? Everything work?

I noticed that as soon as Jen picked up the GPUSB unit that clouds started forming - mandatory upon receipt of all new equipment!

Cheers

[Omaroo]

Hey there Geoff - and thanks for the GPUSB - it works a treat.

Well - as per usual and right on queue - clouds.

I did manage to set up quickly as I'd not torn down the tripod from the night before so was still in reasonable alignment.

During a break in the cover I had guiding going in no time. So - all happy for this weekend!

I took a couple of shots (10 minutes exposure) whilst I could, and ended up with stars that were rubber stamped 4 times in each others' close proximity. I put it down to cloud rolling by and PHD losing the star several times during the exposure. No matter - we'll give it right-royal thrashing over the weekend down at the forest.