Login  Register

Re: Calculation of error ?

Posted by karenacollins on May 19, 2021; 8:55pm
URL: http://astroimagej.170.s1.nabble.com/Calculation-of-error-tp1561p1563.html

Hi Pieter,

Yes, AMag error is in magnitude. However, Source_Error is in ADU (or counts), rather than magnitude. The error will always be given in the same units as the value.

Appendix D in the AIJ paper here describes most or all of the data values found in the measurements table.

Regarding your question: "Do I still have to enter values for the readout and dark current noise, when treating them as in Image Sequence in AstroImageJ ? I did enter the e/ADU value for the gain of the camera, and left those two other values at zero."
- AIJ will still work correctly if readout and dark current are set to zero. However, the photometric errors/uncertainties may be underestimated. This will be less of an issue for bright targets, and more of an issue for faint targets. In either case, only the calculated uncertainties will be affected, not the nominal measured values.

Karen



If you reply to this email, your message will be added to the discussion below:
http://astroimagej.1065399.n5.nabble.com/Calculation-of-error-tp1561.html
To start a new topic under AstroImageJ, email [hidden email]
To unsubscribe from AstroImageJ, click here.
NAML