On 6 Jan 2001, at 14:53, PAUL STENQUIST wrote: I mounted a 200mm > lens on the LX, loaded it with Ektachrome 100VS, and positioned a gray > card in a dim room. With the asa set at 100, and the lens stopped down > to f11, the LX exposed the film for 21 seconds. The ambient light > reading on the spotmeter indicated an exposure of 6 seconds, about 1 1/2 > stops less. This is in keeping with the values on the Adams chart. Of > course the spotmeter cannot be calibrated to correct for reciprocity, > because it doesn't know what aperture I'm going to choose. After writing > down these values, I moved the gray card to an area with more light, > changed the LX meter to 1600asa and made another exposure. The LX meter > indicated 1/30 second at f11, and the audible results of an aperture > priority exposure seemed to confirm it (although I obviously can't be > certain that it was exactly 1/30 second). The spotmeter indicated > exactly the same exposure f11 at 1/30 second for 1600 asa. Based on this > single experiment, I suspect that the LX meter is programmed to correct > for reciprocity failure when making long exposures in aperture priority mode. Very interesting, I will try to replicate the experiment. After learning to leave lengthy exposure timing to the LX auto metering (ie leaning not to fiddle and to trust the force) I have had few failures over many years using many very different film stocks, so I can't help not being surprised about your results :-) Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 Fax +61-2-9554-9259 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://www.ozemail.com.au/~distudio/publications.html This message is from the Pentax-Discuss Mail List. To unsubscribe, visit http://www.pdml.net and follow the directions. Don't forget to visit the PUG at http://pug.komkon.org
