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Tests have been carried out using three the WFPC images retrieved from the HST
Archive.
Observed with PC6, F555W, on 11 April 1991. This is a
256
256 subimage centered at pixel (253,638) in the original
800800 pixel frame.
Observed with PC6, F547M, on 25 August 1990. This
is a 256256 subimage centered at pixel (319,393) in the original
800800 pixel frame.
Observed with PC6, F547M, on 22 November 1991. The
image is a 256256 subimage which includes the nucleus of M87 as
well as the famous jet.
The Library PSFs, Image PSFs, and Tiny TIM PSFs are used for image
restoration in this experiment.
The PSFs retrieved from the WFPC PSF Library cover regions of 200200
pixels (8
8 square). The available PSFs include one for F547M centered
at position (337,328) and three for F555W centered at positions (138,525),
(338,527), and (336,728). The exposure times for these PSF images may not be
long enough to be totally free of the effect of the finite shutter travel speed
for WFPC camera (Holtzman 1991).
An empirical PSF has been extracted from the R136 PC images at the position
shown in Figs. 2 and 4).
PSFs were computed using Version 2.4 of Tiny TIM. For the PC6 images of
R136 the PSF position coincides with the position of the empirical PSF star
used above. For the M87 image the PSF position coincides with the nucleus
of the galaxy.