I get correct exposed Velvia within 1/3s consistently for the three labs I've been using. People expose Velvia at 40ISO because the 1/3s stop difference make a difference. This differece doesn't dissapear in processing or film variations. Pro labs are extremely accurate. So are pro labs. But it doesn't matter if the errors are consistent. Shutters in modern cameras are 100%. So is metering calibration. Consistency is what it is all about. Even if it wasn't, using metering accuracy that are worse than 1/3s makes the exposure errors larger and make the results even more unpredictable. I don't brackett in order to accidentally hit the right exposure. I bracket to have alternative exposures that might or might not work.
Pål ----- Original Message ----- From: "J. C. O'Connell" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, June 09, 2003 10:54 PM Subject: RE: Exposure (WAS: Re: OK Survey time) > 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 > > >
