MODULE: apphot package
SYSTEM: V2.9
NUMBER:	126
MODULE:	apphot package 
SYSTEM:	V2.9
DATE:	Wed Jun 27 16:47:34 MST 1990
FROM:	davis

BUG:	Due to fractional pixel effects the sky fitting routines in apphot
	can fail to preallocate enough space to hold the sky pixels, resulting
	in a memory corruption error or a segmentation violation on exit
	from a task. This condition occurs rarely most often when the sky
	fitting annulus is very narrow. All the apphot tasks which do
	sky fitting are affected.

STATUS:	The bug is fixed in 2.10. There is no workaround although increasing
	the width of the sky fitting annulus slightly may bypass the
	problem. Contact the IRAF group for a fix.

NUMBER:	226
MODULE:	artdata.mkobjects
SYSTEM:	V2.9-V2.10.2
DATE:	Fri Sep 17 14:13:24 MST 1993
FROM:	valdes

BUG:	The scales of the 'expdisk' and 'devauc' images are incorrect due
	to an integer truncation error.  The error is such that the actual
	output radius for a given input radius is given by the formulas:

	expdisk:  rout = rin * int(ln(D)/1.6783) / ln(D)/1.6783
	devauc:   rout = rin * int(ln(D)/7.67)**4) / (ln(D)/7.67)**4

	where D is the dynamic range parameter in the ARTDATA package
	parameters, ln() is the natural logarithm, int() is the integer
	truncation function, and ** is the exponentiation operator.
	From this one can, fudge the input radii to give the
	desired output radii, select a dynamic range where the correction
	factor is 1, or account for this as needed when the artificial
	image is analyzed.  The simplest thing is to adjust the dynamic
	range; for example, a dynamic range of 126514 for the 'expdisk'
	model is the closest to the default value of 10000 which will give
	correct output scales.

STATUS:	Fixed in V2.10.3

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