New PHD2 Development Snapshot

[Drac0]

Hi All,

A new development snapshot of PHD2 has been released, v2.6.12. Hopefully it remains as stable as v2.6.11 proved to be.

https://openphdguiding.org/downloads/

Cheers,
Mark

[Startrek]

Hi Mark,
Thanks for the alert
This latest version should be a game changer for beginners ( and for folk who have calibration issues )
The new Calibration Assistant will probably eliminate a large volume of the posts on the PHD2 forum where folk have issues with guide camera connections, calibration and guiding in general.
Unfortunately the CA will not work directly through imaging software, so folk will have to calibrate separately in PHD2 using the CA and then open their imaging software to guide , dither , capture and so on …..
Bruce Waddington and Brian Valente will be pleased as it should reduce the number of posts they receive.

Cheers
Martin

[TrevorW]

Unfortunately the latest version no longer supports my SSAG - can someone advise best settings when using Predictive PEC algorithm :)

[Startrek]

I’ve been using the PHD2 predictive PEC algorithm on 3 different mounts over the last 6 years

You can either manually enter your worm cycle period of your particular mount by calculating the value yourself ( see below for the 3 different mounts I’ve owned ) or let PHD2 calculate it after tracking for a couple of worm periods by ticking auto adjust box in PPEC algorithm tab
When PHD2 calculates the value it’s always slightly different than mathematically calculating it , but only by a second or two .

Worm Cycle Periods

Earth Sidereal Day = 86,164.1 sec

Worm Cycle Period
Sidereal Day (sec) divided by number of main worm drive ring teeth

HEQ5
86,164.1 / 150 = 574 sec or 9.6 min

EQ6-R
86,164.1 / 180 = 479 sec or 8min

EQ8-R
86,164.1 / 435 = 198 sec or 3.3min

NB: The above worm cycle periods do not factor in any periodic error or inefficient worm gear meshing

Is the above what you’re looking for ??

Cheers
Martin

[TrevorW]

Thanks Martin, do you adjust RA and DEC weight aggression

[Startrek]

No do not fiddle with Ra and Dec weightings

Let the PHD2 PPEC algorithm work it all out

Just remember the algorithm is looking and trying to predict for periodic error on the worm and other spurious harmonic disturbances in your mechanical drive system , not things like wind gusts , bad seeing , or even backlash which are detected by the hysteresis part of the same algorithm.

In order to maximise the algorithm’s performance, your mount should be in reasonable mechanical condition, tuned for backlash, balanced correctly in Ra and Dec , no stiction and so on ……

PHD2 PPEC is not a miracle cure for a bad mount

Worth reading the PHD2 PPEC notes

https://openphdguiding.org/man/Guide_algorithms.htm

I found after using PPEC for a few months it definitely improved my guiding , so I’ve stuck with it ever since , long time now

Martin

[ChrisV]

+1 for ppec. Try it, watch the guiding yourself. Your can eyeball the decrease in worm cycle (and/or other) periodic errors over the first few cycles. I find it calming and reassuring - as there's always some other bug-duggey going on !!!

[TrevorW]

Since the upgrade then reinstall of old version I am now getting an 18s camera time out error for some reason but at the same time another error window pops up saying command not found, either way it doesn't seem to be affecting the guiding. I've also noticed that auto star detect is now choosing the brightest star for some reason whereas previosly would choose a very dim star :)

[Startrek]

Trevor,
I recommend you join the PHD2 forum in Google groups
Post your issue including uploading your guide logs etc… ( the latest manual shows you how to do this )
Bruce or Brian will reply in a timely manner and hopefully resolve your problem
When I started using PHD2 this forum helped me iron out all the errors, mostly self induced in the drivers seat.
These days PHD2 is pretty darn easy to get going , Important for both beginner and experienced “Read the Manual” , get the right guide camera for your rig ( guide scope or OAG ) , use good quality USB cables and test them for connectivity, download all the latest drivers , connect up direct to laptop for Ascom pulse guiding ( not ST4 ) , run and follow the PHD2 Wizard including creating a Dark library, using the Calibration Assistant and Guide Assistant and your on your way !!!

Forgot to mention, I’ve never ran PHD2 through my acquisition software APT , I always launch it separately , run it separately. The only functionality between PHD2 and APT are the dither commands. APT sees PHD2 running but does not control its destiny. I’ve lost count how many times folk post issues on the PHD2 forum with connection issues , drop out issues , meridian flip issues when running PHd2 through their acquisition software like NINA , APT , SGP , ASIair and many others. Some resolve their issues , others don’t .
I like to keep things simple , less room for gremlins and error.

Martin

[TrevorW]

Thanks Martin