NUMBER: 308 MODULE: artdata.mkobjects SYSTEM: V2.9-V2.10.4 DATE: Mon Aug 14 09:55:27 MST 1995 FROM: valdes BUG: When using an image either as a PSF model or as an object model the result is very subtly wrong in the fluxes. The problem showed up when using a symmetrical PSF model and the resulting star or galaxy profile was not symmetric at a low level. The measured centroid was off by 0-0.05 pixels. This is caused by a numerical precision error that occasionally adds an extra subpixel to the flux computed for an output pixel. There is no workaround though the effect can be minimized by using a larger number of subpixels. However, the effect is very small and simulations with added noise would likely swamp the error. STATUS: Fixed in later versions. NUMBER: 393 MODULE: rv.fxcor SYSTEM: V2.11.1 DATE: Tue Feb 17 14:57:11 MST 1998 FROM: fitz BUG: When computing a deblended fit to the correlation peak the task may trigger a 'floating overflow' exception when quitting the deblending routine. STATUS: The bug occurs only when the velocities for each component cannot be computes and are returned as INDEF values. Starting with V2.11 the double-precision value of INDEF was changed to 10e308 and will cause an overflow when it's converted to real when saving values in the task structure. A code change is required to fix this. As a workaround be sure that all necessary keywords are in the image header prior to the correlation so velocities can be computed. A list of missing keywords is printed in the verbose output listing generated by the 'v' keystroke when the 'verbose' parameter is 'long' or 'txtonly', use the initial fit of a single function to get these keywords prior to deblending. Fixed for the next release.
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