Re: PEMPro Data gathering


Hi Mike

generally you want the intersection of celestial equator and meridian. you want to avoid low altitude and near the poles

exposure time doesn't matter as much - a few seconds is fine

regarding noise, PEMPro does a great job of filtering that kind of stuff out. i'd say more cycles would help that. i typically aim for 12-15 cycles

On Sun, Nov 15, 2020 at 7:28 AM Mike Shade <> wrote:

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:


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