PEMPro Data gathering

Mike Shade

Have a few questions on best practices for PemPro data gathering.


1600GTO, early model (just had bearings replaced in RA/DEC gear boxes), Planewave CDK 17/unbinned image scale .631"/pixel/permanent setup


Is it best to gather data at 0 dec (about 55 degrees elevation), or higher (80 degrees) to minimize seeing effects?


If higher data gathering, calibrate here as well?


To minimize seeing effects, better to use a shorter exposure, say .25" and a longer delay between exposures, say 3" OR a longer exposure and longer delay (1" exposure/3" delay)?


When gathering data, I can watch the star in Maxim move quite a bit off of centroid in random directions.  Some is of course real PE, the rest noise.  I know the program can account for this to some extent, but this is a lot of noise and wonder if it is being represented in the final curve.


Generally get about 400 points for a PEC curve, more or less.




Mike J. Shade

Mike J. Shade Photography:


In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights


International Dark Sky Association:



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