EQMOD VS-PEC plus PHD guiding - Question

[mldee]

Having completed my EQ6 Hypertune, I've now moved on to the next stage of measuring PE and using PEC on the mount with EQMOD.

I'm using PERecorder and PecPrep to prepare the EQ VS-PEC files, and all seems to be going OK.

My question is; What sort of numbers should I be looking at for PERecorder raw PE, and after using VS-PEC but no guiding?

Of course the next question then is; what PE should I expect when I use VS-PEC plus PHD/finderguider as well?

I'm not after "lab quality" numbers, just a general feel for what should be my target numbers, as one can spend an awful lot of time fiddling with filter parameters in PECPrep, potentially for little gain.

Cheers,

[mldee]

Hmm, let's try again....

Does anybody actually use VS-PEC with EQMOD?

[RobF]

I am on my Heq5 Mike. Probably won't compare at all nicely to your smooth new hypertuned 6 though! I've still never conclusively proved how much it helps, but is SHOULD. Some pics that have come out particularly tight were during PEC runs, but tthat was also at a dark sky site with very good seeing.

For my Newt on the heq5, I think 80-90% of what matters is good alignment and balance (and cable management, and luck, and no wind, and tracking on the east side, and not having the object too low, and tweaking the guide settings, and good seeing, and .........) :P

[mldee]

Thanks Rob, I was beginning to think I was using the wrong deodorant!

I might go ahead and post my question on the EQMOD Yahoo forum, I was looking there this morning and seems to be some others using PEC, as there are lots of tools for measuring PE, etc, there.

As a side comment, where I'm coming from is trying to work out what needs to be done PEC-file wise when I swap out scopes on the mount. I use an 8" f5 newt, C8, and f6 Megrez. (My "Goldilocks" FL combinations :))

They can all balance well just by adjusting the two weights etc, I'd like to determine how much need for change of the PEC file with that.

With my obs, I find wind isn't much of a factor, PHD settings and Mount balance, certainly are!

I'll post any info here that I find.

Cheers,

[RobF]

Will be fascinating to see if the different scopes give you different curves Mike. In a perfect world I guess there should be almost no difference, but will be interesting to see.

I wish the EQ mounts encoded their positions. I always find myself wondering how long will it take for the encoders to gradually get unsync'd with the PEC even if I religously park/unpark. I guess there are options to PEC adjust your current curve so perhaps its a given you need to somewhat regularly check/update.

[mldee]

Of course rain and clouds have now arrived....

I wanted to see the effect of PEC and PHD, but I found that it was just too much for my eeePC to handle EQMOD, PECRec + Webcam and PHD + DSI II all at the same time. It worked, but started to get seriously slow.

I've now moved the mount-eqpt USB-hub cable over to my Dell Inspiron imaging PC, which at least is a dual core CPU, and all works well in a dry run. No need to image while I'm doing this, so no Neb + QHY8 needed to run on the Dell.

When the sky clears, I'll see what I can find.

Cheers,