Trilogy: FITS image conversion software

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Ada Coda
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Trilogy: FITS image conversion software

Post by Ada Coda » Sun Aug 30, 2015 8:06 pm

Trilogy: FITS image conversion software

Abstract: Trilogy automatically scales and combines FITS images to produce color or grayscale images using Python scripts. The user assigns images to each color channel (RGB) or a single image to grayscale luminosity. Trilogy determines the intensity scaling automatically and independently in each channel to display faint features without saturating bright features. Each channel's scaling is determined based on a sample of the image (or summed images) and two input parameters. One parameter sets the output luminosity of "the noise," currently determined as 1-sigma above the sigma-clipped mean. The other parameter sets what fraction of the data (if any) in the sample region should be allowed to saturate. Default values for these parameters (0.15% and 0.001%, respectively) work well, but the user is able to adjust them. The scaling is accomplished using the logarithmic function y = a log(kx + 1) clipped between 0 and 1, where a and k are constants determined based on the data and desired scaling parameters as described above.

Credit: Coe, Dan


Bibcode: 2015ascl.soft08009C

ID: ascl:1508.009
Last edited by Ada Coda on Sun May 03, 2020 10:22 pm, edited 1 time in total.
Reason: Updated code entry.

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