ISIS bug - predefined dispersion used with reference line

ISIS bug - predefined dispersion used with reference line

Postby Robin Leadbeater » Sat May 09, 2020 3:04 pm

ISIS has a useful feature where the predefined dispersion equation mode can be used with a single reference line which uses the same dispersion equation but recalculates the offset coefficent A0 based on a single reference line (Normally you enter 0,0 for the reference line which forces ISIS to use the full predefined dispersion equation. If you enter the wavelength of a line and the approximate position in pixels in the calibration image it uses this instead.)

This correctly shifts the calibrated spectrum as expected but it calculates the spectrum over the original wavelength range. This produces incorrect constant values on one edge and crops the other edge of the spectrum.

ISIS V5.9.3

ISIS_predifined_dispersion_bug.png (18.28 KiB) Viewed 346 times
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Re: ISIS bug - predefined dispersion used with reference li

Postby Ken Harrison » Mon May 11, 2020 8:45 am

I thought it was only me......
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