Here are the images of DCM spot measurements from the XRCF. For these measurements, the background rates are very high; normal background rates are < 0.5 evts/sec. This problem had been occuring with the HRI MCP for several weeks, and wasn't corrected until about a week later when Murray and Chappell brought a new MCP from SAO and installed it.
There were "anti-gaps" in the raw images likely due to incorrect gain settings for the preamps. To create a gap map for these data, all the background images from May 14 and May 15 were added together and the gaps adjusted to make the resulting image smooth. The gap parameters were not constrained and this allows a simple correction to be made for the antigaps. The resulting gap file was called bk96may.gap.
The HRIFIT screen output was changed slightly. It now always reports the number of "overflow" events. This was done to see if overflow events accounted for a large part of the background (they don't). There were no other changes to the software and the output FITS files should not have changed.
The overlay grid has a spacing of 500 microns (0.5 mm). The GIF images only show part of the total FITS image.
Magnification = 1.06 +/- 0.01 Data taken = 1996-05-13/1996-05-15 Pinhole size = 40 micron VHRIFIT = 1999-03-01 GAPFIL = bk96may.gap VLEXTRCT = 1999-01-20To get a compressed tar file of all the FITS images in this sequence click here: FITS data.