[condebob (Bob)]

Colleagues

I've recently started using a Losmandy Titan mount and have found that the default worm period in PEMPro does not give the best results for my mount.

This is my first Losmandy, so I don't have a great deal of experience with these mounts, but I've been pretty happy with the PE, which is around 8 arcsec peak to peak. Not bad given that it will be used with a self guided slit spectrometer.

But my asperger's will never let good enough go unchallenged, so I started messing about with PEMPro in order to reduce the PE to as little as possible.

The default worm period in PEMPro was 319.13sec, which was about what I had read on the web. Ive also seen a number of PEMPro uploads with the period at 319. After running PEMPro for a while a PEC curve was built to fit to fit. Once uploaded the curve ran the mount at between 2 and 4 arcsec most of the time with spots going back to around 7 arcsec, so not much of an improvement at all...

Attachment 1 shows the plotted data from PEMPro with the 319 second worm period. Kinda curvy, but with lots of noise. The seeing here has been rubbish this last week, so I assumed that had something to do with it.

There is a function in PEMPro which allows you to view each cycle, so I flicked through and noticed that every second cycle showed real similarities, so I change the worm period from 319 to 638 seconds and WHAM, all the noise vanished and a distinct set of curves appeared with less than 1 arcsec var. for the curves. Attachment 2 has the 638sec curves.

The PEC is ready to upload whenever the damn clouds vanish.

Grateful for any advice or comment on these curves please

Cheers!

Bob Lester
Canberra