The International Space Station (ISS) flies overhead every day. Not all passes are visible because some occur during the day and others occur while the ISS is in the Earth’s shadow. The most interesting passes are those that occur low to the horizon and then enter the Earth shadow.
During the evening of 21 April, the ISS rose in the northwest just below the constellation Cassiopeia then moved above the San Francisco Peaks. Finally, as it moved to the northeast it faded in brightness as it entered Earth’s shadow.
Well, it seems you CAN shoot the ISS through some cluods.Note that this shot used a which is more naturally white but NOT suitable for visual observing. The texture of the cluods is pretty obvious but the sunspots are also nonetheless visible. Because the cluods were rolling by, I elected to shoot the images in AV mode to handle the abrupt changes in brightness. The shot with the ISS was taken at 1/2000s of a second at ISO 100. The equipment consisted of: a 600mm Orion ED80 refractor telescope, a Canon 1.4x Tele-extender, a Canon 50D all on an Orion Astroview equatorial mount (though the mount was only used as a glorified tripod).The effective focal length of the shot is therefore 1344mm and the effective f/stop is 16.8.