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AZ-EQ6 GT Periodical error and guiding performance

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Hello,

I need the the help of you guys in analysing my mount's PE and maybe tuning my guiding performance. So far I've been using the PHD settings almost on default but I've now decided it's time to make the jump and learn if and how to fine tune them.

My setup consists of a AZ-EQ6 GT used with EQMOD, the scope is a SW ED80 with a 0.8 focal reducer (so my imaging FL is 480mm), the imaging camera is an Atik 460ex mono. Im guiding through a TS 60mm f4 guidescope (240mm FL) with a QHY5 camera piggybacked on the ED80. So, I'm imaging at 1.95"/px for bin 1x1 and at 3.9"/px at bin 2x2 and my guiding resolution is 4.47"/px. The whole setup is a mobile one, so I set-up and take everything apart after each session.

Last weekend I decided to give Periodical Error Correction a try and used the automatic tool included with the EQMOD. Just by visually analyzing the PHD guide log I see there's a slight improvement (see "guiding_session_overview.jpg" printscreen from PHD2 Log Viewer): to my eyes there's a change (in good) after second half of the graph). I loaded the PERecorder file into PECPrep for analysis and this is what I got ("PECPrep_overview.jpg"). I'm having a bit of a hard time understanding the numbers as I don't have what to compare against. Are those numbers good or does the mount require some tweeking? What is the PE of my mount (I'm curious to see how it compares to figures from other mounts)? Should I look at the RMS PE, or Peak PE?

Zooming in on the PHD log I noticed that there's some "bounce" on both RA and DEC when making corrections (see "DEC_bounce_example.jpg" and "RA_bounce_example.jpg"). I belive the "official" term is that PHD is overcorrecting. From what I've read I should decrease the aggression and/or hysteresis parameters. Am I right or the "bounce" is not that bad? Should I also alter some other parameters? I've also attached the PHD guide log form that evening. My "target" is to try and reach the 30min subs mark. 

Thanks and clear skies,
Andrei

DEC_bounce_example.jpg

guiding_session_overview.jpg

pecapture_07022016234934_EQMOD.txt

PECPrep_overview.jpg

PHD2_GuideLog_2016-07-02_221125.txt

RA_bounce_example.jpg

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I'm also looking at PEC and PECprep for the 1st time.

Have you had any further information from anyone on your questions?

How are your images coming out?

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