Fig. 4.11-II : example of an exposure taken on the ground (MPE Panter facility) with optics (source at 5.7 arcmin off-axis) This particular exposure is in Al light (1.5 keV) and contains 470,000 photons.

sax.iasf-milano.inaf.it/Sax/Mecs/figmuoff.html :: original creation 1998 Sep 18 18:51:24 CEST :: last edit 1998 Sep 18 18:51:24 CEST