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A Galaxy White Balance Test With

AstroDon E-Series & Baader Filters

 The "mouse-over" view is with Baader filters.

 
 

 The "mouse-over" view is with Baader filters.

Instrument

Takahashi FSQ-106ED @ f/5.0 (530 mm F.L.) Captured at 2.1 arcsec/pixel.  Shown at 8.46 arcsec/pixel.

Mount

Paramount MyT

Camera

SBIG STF-8300M Self Guiding Package w/ mono ST-i, using AstroDon E-Series and Baader RGB filters.

Exposure AstroDon

RGB

 147 min. (7 x 7 min. each)  binned 1x1

 RGB combine ratios are 1.00, 0.95, 0.95

Exposure   Baader

RGB

 147 min. (7 x 7 min. each)  binned 1x1

 RGB combine ratios are 1.00, 1.19 1.53

Software

  • CCDSoft, PixInsight & Photoshop CS6.

  • eXcalibrator v5.0 for (g:r) white balancing, using 206 stars from the SDSS-DR9 database.

  • CCDStack for calibration, normalization, data rejection, stacking and creating the two RGB images.

  • PixInsight processing includes gradient removal and non-linear stretching with HistogramTransformation.

Comment

The processing for the two images is identical. They were processed together... step by step.

We can clearly see that different filters can produce noticeably different results, even when the images are white-balanced with an identical process.

The AstroDon E-Series filters are designed for use with "full frame" sensors, like the one used in this test. The Baader filters are designed for Interline sensors, such as the KAI-110002.

The normal image train RGB calibration ratios, for the Baader filters, are 1.00, 1.20 & 1.42. For the AstroDon filters, the RGB calibration numbers are 1.00, 0.92 & 0.90. The final eXcalibrator RGB ratios will very from image to image.