Hello, So that I may know what to expect when trying to record flashing satellites etc. I did some starlight magnitude tests with my Sony digital video camera [DCR TRV 340]. Following are the results. The lens setting was 50 mm, F 2.4 at 20X magnification. The imaging device is a 1/6", 460K gross pixels CCD. The video was actually 290K Pixels. The minimum illumination capable of being perceived is 4 Lux Using the so-called "NightShot" mode I could barely see a star that was mag. +3. Using the "Super NightShot" mode I could barely see a star that was mag. +6. I have not yet tried the "Color Slow Shutter." At least I don't think I did. :~) I'm just learning how to use the camera. Using the Super NightShot mode the shutter speed must have been the slowest the camera can shoot at, that is 1/4 second. In this mode any movement of the camera made the bright stars streak momentarily. The image appeared to be stepped at 1/4 second intervals and was very noisy indeed. According to Sony the Super NightShot mode is about 16 times brighter than straight NightShot. Now can someone tell me how 16 times correlates to 3 magnitudes in brightness? Thanks! Tom Iowa USA ..... P.S. I recently drilled holes in a board and mounted my digital video camera, next to my binoculars, next to my night vision scope, next to my Coolpix digital camera. On the board I also have an angle finder to approximate the altitude so as to zero in on flashing geosyncs with minimal star-hopping needed in my light polluted skies. I will use it on a tripod and aim it at Superbird A (and others). When I see the satellite flashing in the 2X night vision scope I will look for it in the 7X binoculars. When I center it in those I will know that it is centered in my video camera, even at 20X. I will then try to video tape the flashes. I may be able to use the Coolpix for in some way too. I sometimes have a difficult time spotting Superbird A in my binoculars but find it easy to spot with the 2X night vision scope. Now I can find it first in one then in the other. Without this setup I do not believe I could find the intermittent flashes of Superbird A at 20X using my video camera. Now if the clouds would go away I would be all set! ----------------------------------------------------------------- To unsubscribe from SeeSat-L, send a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@satobs.org List archived at http://www.satobs.org/seesat/seesatindex.html
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