Description:
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When creating 16-bit FITS file, a value of BZERO header is set literaly to "3.276750E+04", what is 32767.5
In this case it is impossible to store correct pixel value in 16-bits, as it's calculated as follows:
true_pixel_value = array_value * BSCALE + BZERO


Test script:
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$im= new Imagick();
$im->newImage(1,1,'none','FITS');
$im->setImageDepth(16);
$im->writeImage('file.fit');
$im->destroy();


Expected result:
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Value 32768 is used instead for BZERO.

Actual result:
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BZERO is 3.276750E+04