[daip] New Client Reply - [!NXD-300275]: MAXFIT no longer working

[Michael Bietenholz]

New Client Reply: MAXFIT no longer working

Never mind - I figured out all I needed was to "RUN NEWPARMS"

However, I've noticed another strange thing:  MAXFI returns a value that is systematically *lower* than the peak pixel brightness.  For example, if I use IMMOD to create an image with a beam-sized (3.8 x 3.7 pixels FWHM in my case) Guassian, with FACTOR=0, and centered on pixel 256,257 then I find:

peak pixel brightness =  1.000 Jy (as expected)
IMVAL (pixxy 256 257) = 1.000
JMFIT   peak                = 1.000
MAXFIT                        = 0.985

Its not a huge difference, but its ~1.4%, far larger than any numerical issues should be.  Since its a nice,
noise-free, beam-shaped Gaussian centered on a pixel, it seems rather odd that MAXFIT returns a value 1.4% lower than either brightness of pixel 256,257 or that returned by JMFIT.   I've noticed before that MAXFIT often returns a value slightly *lower* than the brightest pixel, which seems like it should never, or
at least only rarely happen, so I don't think its to do with this particular image.

Ticket Details
===================
Ticket ID: NXD-300275
Department: AIPS Data Processing
Priority: Default
Status: Open
Link:  https://help.nrao.edu/staff/index.php?_m=tickets&_a=viewticket&ticketid=3119