First of all, you will rarely if ever get "perfect" exposures with any TTL metering system due to the way they only measure reflected light.
Secondly, there are exposure errors that occur in shutters both from speed to speed as well as from exposure to exposure even when set on same speed. Thirdly, there are exposure errors in the aperture when changed from fstop to stop. This throws off the TTL metering when using open-aperture metering as it assumes perfectly accurate stopping down. Even if you use a hand held meter, the error will still occur due to aperture variations from perfect. Fourth, there are speed inconsistancies in a given film from batch to batch. Fifth, many times with slide film there is no "perfect" exposure, variations around what is theoretically perfect just give slightly different interpretations of the same scene. This is another reason why some people bracket, to make sure they get just what they want. I think your quest for "perfect" exposures on all rolls of slide film is unrealististic, impossible, and thankfully unnecessary with the prudent use of bracketing techniques.... JCO > -----Original Message----- > From: Pål Jensen [mailto:[EMAIL PROTECTED] > Sent: Monday, June 09, 2003 4:24 PM > To: [EMAIL PROTECTED] > Subject: Exposure (WAS: Re: OK Survey time) > > > Caveman wrote: > > > > Ahhgad. Here we have a measurbator. > > I haven't met single photographer who don't want to nail the > exposure dead on. I want consistent exposure and I want it > without wasting film. > It is OK to like the LX meter. It is OK to prefer it. But have > you actually extensive experience with matrix meters calibrated > for slide film? Or spotmetering for the tonality of various > colors? I've used the LX 22 years and know everything about it. > It cannot give the same precision the 645n or the MZ-S gives and > this is important for 99% of all serious amateurs and > professionals alike. > > > If I'm not too pushy: > > - how do you define what a perfectly accurate exposure is > > A perfect exposure is what I define as a perfect exposure. I want > that exposure within 1/3 of a stop so that I can get what I > define as perfect exposure every time. . > > > - how do you describe the effect of a 1/3 deviation from the above > > 1/3 stop deviation is clearly visible on film like Velvia. 1/2s > off on Velvia may ruin a shot. Thats why I want to have 1/3s accuracy. > You have obviously never received a roll of film with all > exposures wuthin 1/3s of the correct one. Neither have I with the > LX. The thing is about consistency. Not what exactly is correct > exposure. You may not want that precision. Thats fine by me. > > > Pål >
