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Entropy
15-08-2017, 06:55 PM
Evening All.

I'm trying to capture some PEC data using PHD2. Everywhere I read about capturing PEC data says to make sure Guiding is switched off, yet I can not find an option anywhere to do that.

Am I going insane? What am I doing wrong? What's the best way to capture PEC data for PECPREP using PHD2?

Thanks

Entropy

codemonkey
15-08-2017, 07:11 PM
https://openphdguiding.org/man/Advanced_settings.htm#Guiding_Tab

Click the "brain" icon, then go into the Guiding tab. Down the bottom left there's a checkbox which says "Enable mount guide output" - that's the one you're looking for. Unchecking that disables guiding.

RobF
15-08-2017, 07:13 PM
Best way is to do it inside EQMOD if you can.

Set the two filters up a bit - say about 1/5 and 1/3 across respectively, then record at least 4 worm cycles.

Repeat later if need to adjust further. Works really well in the later versions of EQMOD.

Entropy
15-08-2017, 07:34 PM
Thanks Lee, That's exactly what I was too blind to see, Sorry about the dumb question.
Rob, I will definitely have to try that. Is that using AutoPEC?
Am I right in assuming I can image and capture PEC Data at the same time? And this will be better quality data than PHD Guide Logs?

Entropy

RobF
15-08-2017, 07:57 PM
Yes, autoPEC.

The downsides of doing AutoPEC though:

- you have to make sure PHD keeps guiding indefinitely (e.g. no pausing, or dithering if you're integrating it with something else like Sequence Generator - unless you run very long exposures like say 1 hour)

- I find I have to increase the filter settings a bit to smooth out the resulting PE curve.

Its probably worth going through the PECPrep workflow a couple of times just to understand how the high/low/magnitude filters work and get a feeling for what sort of curve and PE you have to deal with.

Entropy
16-08-2017, 08:49 AM
Thank you for all your help.
I managed to capture something last night. Does this look reasonable?
Am I on the right track?

Side question, anyone here heading up to Astrofest this Friday?

Thanks again

Entropy
BTW Mount is an EQ8

https://www.flickr.com/gp/143524340@N05/n6Zf31

RobF
16-08-2017, 09:07 AM
Wow, if that was done with autoguiding off you have a great EQ8. Almost doesn't need PE correction.

Entropy
16-08-2017, 11:14 AM
That was just the output from AUTOPEC. Does this tell me nothing? I will try the PHD log tonight.

Entropy

RobF
16-08-2017, 11:36 AM
Definitely worth doing it via PHD so you have more confidence in both methods.
My guess is that's PE curve is representative however - the EQ8s seem to be great mounts in general - much larger gears for a start.

Entropy
16-08-2017, 09:01 PM
Just did about 10 cycles of my EQ8 and captured the data using PHD2 (Guiding Off)
This graph looks a lot more realistic - but the resultant PEC says I should have a residual of about 2.3 arcsecs, which sounds pretty good to my uneducated ears.

Here's the graph for the interested

https://www.flickr.com/gp/143524340@N05/Cw57PZ

Thanks for your help. Onwards and upwards... continuing to capture data for my first foray into NB imaging (Eagle Nebula)

Entropy