Imaging, guiding and observing

[LAW (Murphy)]

Hey everyone, I've been reading about autoguiders all day, ST-4, EQMOD, standalone and PC driven but I think I know less now than I did this morning.

I have an EQ6 without a guide port, an 8" F/5 newt. I have a 60mm guidescope but I also have an Orion off-axis guider. I don't have a guide camera yet but I'm leaning towards the QHY-5.

The Shoestring Astronomy GPUSB with hand controller mod looks like a good setup for a good price, combined with PHD software. But I've heard a lot of talk about EQMOD too, but I don't really understand what it does or whether it'll even work with my mount?

[billdan (Bill)]

Good day Murphy,

If you want to keep things simple only use the ST4 port, direct from guide camera to EQ6 mount.

The ST4 port signals are fed directly (controlled by PHD) to the RA/DEC motors.

If you guide via the DB9 ports (on the mount or through the handset) then there is a delay for the microprocessor (about 250mSec) in the mount to respond to the PHD command.

Disadvantage of the ST4 port is that it cannot do RA and DEC simultaneously must be one command followed by another, whereas EQASCOM through the DB9 port can do both at the same time.

With good polar alignment there shouldn’t be that many DEC commands issued anyway, so in practical terms it doesn’t matter.

Regards
Bill

[LAW (Murphy)]

Thanks Bill, that's exactly what I was after. ST-4 into the controller mod sounds good to start with, nice and simple.

Thanks.

[Moon (James)]

I have an EQ6 without a guide port

I think you have one of the older black EQ6s - it's not an EQ6 Pro. You can get an upgrade kit that will add a guide port, like this:
LINK
James

[LAW (Murphy)]

Yeah, It's an older model but she can still learn a few new tricks
I was going to do this mod to give it ST-4 capability >>> http://www.store.shoestringastronomy.com/eq_mod.pdf
And use this USB>RJ12 adapter because my laptop doesn't have a serial port.
http://www.store.shoestringastronomy.com/gpusb.htm

I don't really need the extra features of the 'pro' and the mod only costs around $100 so at this stage I'd rather keep it simple.

Am I right in thinking that this setup will allow me to use the modded hand controller directly from PHD as an ST4 and EQMOD through ASCOM?