ST4 or pulseguiding

[Robfal]

Just been reading the EQmod manual (I know, I'm sad) and realised that I can guide using either of these methods. However which is the best. Up to now I've used the ST4 connection from my QHY5 direct to the mount and that works well. However I could pulse guide from PHD through Eqmod to the mount using pulse guiding

Which, though, is better?

I understand that if I pulse guide then I can also use Pec training (never done that either)

Comments please

Rob

[SteveL]

Apart from being able to use PEC with pulseguide via EQMOD, I am not sure there is all that much between the two.

Purists and longer term imagers will say the ST4 is the way to go because the signal gets to the mount quicker, but even with your QHY5, the decision to move the mount for guiding is still done by the PC, and the signal is sent to the QHY5 and then on to the mount, which cant be any (or much) faster than the PC sending a signal to the handset via serial which then sends the commands to the mount.

If you already have a cable going to the handset for goto control, then not using ST4 save you one cable, but try both one night and see...

[blinky]

I use Pulse guiding, I think 'in theory' ST4 is slightly better as there is 'in theory' less latency. I would use whatever works for you!

[Robfal]

I must say, my current set-up works so I'm a little loathe to change for the sake of it, unless there is a big improvement

Rob

[SteveL]

If it aint broke, dont fix it. If you get an evening where you have managed to set up early and waiting for real astro dark, might be worth trying pulseguide in twilight, then swap back to ST4 for the real image.

You`ll never know unless you try, but I wouldnt waste real imaging time on it if your current setup works.

[George]

I've only ever used pulseguiding with eqmod and never had any issues.

just my experience

[chrisshillito]

For EQMOD I wrote some supplementary notes on guiding and PEC considerations that includes ST4 v. Pulseguiding. http://eq-mod.sourceforge.net/docs/PEC_and_guiding.pdf

The speed of reponse of ST4 v.PulseGuide is typicaly insignificant when considered in the context of the lags introduced by image capture and the guiding alogorithm itself (which may stack or average several frames) .

Chris.

[George]

Thanks for the clarification Chris