Does anyone know the Guide Speed for the Planewave L mounts?

[E M]

I am going through the Wizard to set up a new guide camera for PHD2, and came to a point where it is asking for the guide-speed of the mount.  I have a Planewave L-500 mount but I have no idea what it's guide-speed is.  Does anyone know what the guide speed is for the Planewave L-500 mount?  Or any of the Planewave L mounts?  Thanks.

Ed

[mj.w...@gmail.com]

Hi Ed

I couldn't find any info online for guide rates, the Planewave instructions only describe autoguiding with The Sky.

You could Calibrate with PHD2 using an ASCOM connection.

Then make a short guided session.

Then open the PHD2 GuideLog, and in the settings preamble for the guided section, look for the guide rates read from the mount, and the guide rates calculated during the Cal.

Michael

Wiltshire UK

[E M]

Thanks Michael.  That may be necessary.  I opened a ticket with Planewave today and asked them what their guide rate is for the L series mounts, but they did not know off hand.  It kind of surprised me, as many people use PHD2 software and Planewave hardware.  Is this the first time anyone has asked this question??  Perhaps..  In any case the support rep said he would look into it this coming week and get back to me with an answer.  The method you suggest sounds like the best way to find the true guide rate, so if Planewave cannot provide a confident answer, that is the method I will use.

Ed

Vail, Arizona

[Bruce Waddington]

Hi Ed.  I don’t know how familiar you are with these mounts, so forgive me if I’m telling you things you already know.  Once properly tuned for your setup, these mounts are extremely accurate and can run unguided for quite a while.  If you’re using a small-pixel CMOS camera or are imaging from a suburban location, you may be able to image un-guided.  If you do need to guide, the best approach will be to do so very conservatively, the idea being to only correct for low-period drift.  For example, you may want to issue guide commands only every 10 seconds or so.  There are a couple of ways to do that in the current release of PHD2.  You can simply use long guide camera exposure times – say 8-10 seconds – or you can use shorter exposure times and set the PHD2 time-lapse property to make up the difference between the exposure time and the desired guiding interval.  In an upcoming release, we are adding a variable-delay mechanism that will make this more convenient.  The thing you want is to avoid having the guiding influenced by seeing effects because rapid guide pulses could interfere with the built-in encoder corrections in the mount. That probably translates into using 4+ second guide camera exposure times and being careful to set the MinMove parameters conservatively.  You should also use the LowPass2 algorithm on both axes.

 

With regard to the guide speed, the mount has an ASCOM driver and it probably supports a number of guide speeds.  In that case, it’s up to you to select an appropriate value.  We suggest using high guide speeds, up to 1x sidereal, in order to get quick response from the mount.

 

Good luck,

Bruce

--
You received this message because you are subscribed to the Google Groups "Open PHD Guiding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to open-phd-guidi...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/open-phd-guiding/9624a4ee-913c-46e4-a7c5-f10444917395n%40googlegroups.com.

[E M]

Thanks Bruce,  I set the exposure time to 10 seconds, and I set the algorithm on both axes to Lowpass2.  The driver for the mount (PWI4) does not appear to have a setting for Guide Speed.  I opened a ticket with Planewave, and after looking into it with their programmers they suggested that I use 0.5.  Would you recommend that I use 1.0 instead of 0.5?

[Bruce Waddington]

The mount guide speed is what it is, you can’t change it in PHD2.  PW has probably set it to 0.5x so that’s what you should specify in the new-profile-wizard.  It’s used to set an appropriate value for the calibration step-size, it won’t have any effect on guiding after the calibration is completed.

To view this discussion on the web visit https://groups.google.com/d/msgid/open-phd-guiding/9dd86050-122c-4eac-9028-0ce0262b545dn%40googlegroups.com.

[E M]

Ok, I see.  I will leave it where it is then.  Thank you for your help.

Ed