Paramount MX Mount Testing

Software Bisque Paramount-MX Mount Testing

March 2nd, 2013

Telescope and CCD camera used for mount testing: Planewave Instruments CDK 12.5 Corrected Dall-Kirkham OTA, and SBIG STL-11000M camera

Mount analysis software used during testing: PEMPro V 2.7

See full-resolution photo of above setup here

PEMPro Mount Analysis:

Uncorrected Periodic Error and Secondary Gear Harmonics:

Secondary Gear Harmonics-Uncorrected:

The largest secondary gear error has an amplitude of approx. 1/3 arc-second. This will be very unlikely to show up by affecting star shapes in high-resolution imaging (see test image below). The Freq. 1: 1.428 arc-sec error is a drift-fitting PEMPro artifact and can be ignored for the purposes of PE analysis.

Corrected Periodic Error and Secondary Gear Harmonics:
The PE was reduced from 3.42 arc-sec down to 1.19 arc-sec by PEMPro V.2.7, using a data sample of 6 full uncorrected worm cycles programmed back into the mount by PEMPro.
Playback data sample was 3 complete worm cycles.

Secondary gear harmonics with PEC activated on mount:

Largest secondary gear error is now 0.203 arc-sec with PEC activated on mount.

Test Photo of M38, using autoguiding on Paramount-MX mount with PEC enabled on mount:

Test photo shows excellent tracking and autoguiding capability. Star shapes are concentric and consistent field wide, indicating no tracking or autoguiding problems with this mount. Image resolution is 1.6 arc-seconds/pixel and was reduced from original 0.73 arc-sec scale and 4008 pixel size to fit on-screen better. High res. versions of this image also showed the same concentric and symmetrical star shapes field-wide before processing. Note, due to the presence of heavy moonlight pollution and severe light gradients in the image stack, it was necessary to clip major portions of the black point and apply heavy light gradient removal tools. This resulted in washed-out star color and sky background. It also caused background stars to be overly dim in order to remove most of the light pollution artifacts. But the image is still useful for mount tracking and autoguiding analysis.

Image Details:

Instrument: Planewave CDK 12.5 @ f/8 (2544mm)
Mount: Software Bisque Paramount-MX
Image Scale: 1.6 arc-seconds per pixel after processing
Camera: SBIG STL-11000 with Internal Color Filter Carousel and Astrodon Gen. II LRGB filters
Filters & Exposure Times:
- L: 4 x 5 minutes binned 1 x 1
- R: 2 x 5 minutes binned 2 x 2
  G: 2 x 5 minutes binned 2 x 2
  B: 2 x 5 minutes binned 2 x 2
- Total equivalent unbinned exposure time of 80 minutes
Software: Maxim DL/CCD, Adobe Photoshop CS2, RC Astro Gradient X-Terminator
Location: Little Rock, AR., El. 300ft
Date: February 24th-March 2nd, 2013

Wade Van Arsdale
Little Rock, AR., USA
March 8th, 2013