HEQ5 pro synscan guiding

[LouisJB]

Hi,

I'm a complete novice. I've got a 130P (EQ2) and after failed attempts to take any pictures other than of the Moon (using DSLR for now) I've ordered an HEQ5 pro synscan. I'd like to get guiding working with the 130P and do some imaging then finally I'll upgrade the tube.

My question is this.

I have a macbook pro. I thought I'd probably use PHD guiding software. I'll get a USB webcam and some sort of small guider-scope.

Initially I thought I needed the USB ST-4 adapter (shoestring GPUSB) and plug the laptop direct to the ST-4 on the mount.

However, I might like to use software like Stellarium to goto the mount from time to time.

I don't think this can be done (slewing/goto) over the ST-4 port?

In which case, should I use a USB to serial adapter and connect the laptop to the handset. I think that allows goto positioning from software (right?) and alternative guiding control from say PHD. Am I correct here? Can I goto from the laptop and then guide or will I get software conflicts etc.

Is the guiding the same over ST-4 vs. serial (accuracy etc) - the USB-serial option seems cheaper as I think USB to serials are £10-20 and the GPUSB more like £75-80.

Can someone tell me exactly what I need to order in each case and the pros/cons of each, please?

Many thanks,

Louis

[Steve Ward]

Welcome to the forum Louis .... 

I'm not up to speed with PHD myself and have no idea regarding Macs but I'm sure someone will be along soon to point you in the right direction.

I use the Synguider stand-alone guider myself , that plugs into the mount directly bypassing the laptop , good for 30 minute exposures which is more than plenty for DSLR use I find.

[Merlin66]

Louis,

The mount can be controlled via the handcontroller using any planetarium program ( I use CdC) - this gives GOTO etc etc.

The guiding, through the ST-4 port is completely independent and has no real conflict with your planetarium program.

(I use a Lodestar/ PHD for guiding)

HTH

[Russe]

PHD works with Mac's or Windows PC's.

You need to differentiate tracking from guiding.

For tracking you need a motorised mount - like the HEQ5. But many other will do.

For guiding you don't need an ST4 port - that's only for guide cameras that have an inbuilt chip to send "push here" commands themselves - like the QHY cams for example.

For moon pictures you don't need guiding.

With the HEQ5 you could track successfully for approx. 60 to 120s without guiding, if your polar alignment is good.

Does that make any sense?

[LouisJB]

Hi, thanks for the replies so far. I'm starting to get the idea now I think.

To clarify, this is not for pics of the moon but for some long exposures of galaxies and nebula etc. I realise I can get unguided tracking from the mount (which I'll try for sure), but my ability to get accurate polar alignment every time is not certain and accurate drift alignment would eat into my available time for capturing images. In any case I might want to take long 5minute shots etc of really faint things, so hence the specific guiding (not tracking) questions.

So from what has been said already, I can guide using either port. Since PHD + webcam is cheaper than a dedicated auto-guider then this seems a good way to get started. This can control the mount over USB-Serial or GPUSB-ST-4, but again if there's nothing in it guiding control-wise then a USB-serial converter and serial lead is the cheaper way to get started.

This would also allow planetarium software to goto my mount if I wanted. However, whether I can use both bits of software or have to shut one down I guess I'll just have to try it out and see.

Anyone else got this sort of setup? I'd like to get relatively reasonable guiding for a reasonable price and that way I can put more into the tube upgrade when I'm ready, but conversely I don't want to get the wrong equipment because it's cheaper initially only to realise it won't do what I want longer term.

thanks again for the advice.

Louis