Allan Leader Posted March 3, 2005 Share Posted March 3, 2005 Hi everyone, What type of asa ratings are operators using for their SDX 900 cameras in 24P and 60i ? Thanks very much. al leader Link to comment Share on other sites More sharing options...
Premium Member Laurent Andrieux Posted March 7, 2005 Premium Member Share Posted March 7, 2005 Sorry I don't esp know this camera, but if you have the camera specifications, it's easy to determine. They give you a recommend f-stop at a certain illumination, for instance (and it may be the figure for this one) 2000 lux (or 200 fc) f 11. If you have a meter that displays either fc or lux, it's possible to determine experimentally from this figure. Otherwise, do this calculation : S(asa) = f²X250/tXI where f is the f stop, t the exposure time (1/60, 1/50 and mind that deviding by t is then multiplying by either 60 or 50) and I the required illumination in lux . For instance you'll get S = 11²X250X50/2000 that comes close to 800 If you don't have the camera user's guide, do you have a wafeform monitor ? A luxmeter ? Link to comment Share on other sites More sharing options...
Premium Member John Ealer Posted March 23, 2005 Premium Member Share Posted March 23, 2005 Sorry I don't esp know this camera, but if you have the camera specifications, it's easy to determine. They give you a recommend f-stop at a certain illumination, for instance (and it may be the figure for this one) 2000 lux (or 200 fc) f 11. If you have a meter that displays either fc or lux, it's possible to determine experimentally from this figure. Otherwise, do this calculation : S(asa) = f²X250/tXI where f is the f stop, t the exposure time (1/60, 1/50 and mind that deviding by t is then multiplying by either 60 or 50) and I the required illumination in lux . For instance you'll get S = 11²X250X50/2000 that comes close to 800 If you don't have the camera user's guide, do you have a wafeform monitor ? A luxmeter ? <{POST_SNAPBACK}> Depending on how the camera is setup (gamma mode, slope, etc.) I usually find the effective ASA of the 900 is between 640 and 1000 ASA. J Link to comment Share on other sites More sharing options...
Premium Member Laurent Andrieux Posted March 23, 2005 Premium Member Share Posted March 23, 2005 And the value beetween 640 and 1000 is 800... Link to comment Share on other sites More sharing options...
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