P3D Re: Classic Light Meter

[Eric Goldstein <egoldste@xxxxxx>]

Andrea Blair wrote:

> Meters are easily tested, so if an older model is
> accurate, why not use it?

Andrea:

I wish this were true. Meters are not easily tested without calibrated
equipment. Simply pointing your meter at an 18% grey card on a sunny day
to confirm a reading of f/16 does not tell you anything about linearity
or memory effects or the low light performance of the meter. Even
testing good modern meters in this crude way will often yield one to two
stop variations in indication. Further, selenium meters can be irratic -
seemingly accurate one day and not the next. Often, pushing in on the
front cell can change the reading substantially! 

Why not use such a meter? Because you could easily achieve better
results from exposure tables. For interiors especially where most folks
really need there meters, old selenium meters are usually so non-linear
as to be several stops off; again, you could easily be better off with
exposure tables.

If budget is an issue, perhaps a more prudent course would be to invest
the eight bucks in film and processing and run some test exposures with
common setups and take notes. Ultimately this is what pros do, shoot
polariods and judge exposure and contrast from the film and not from the
meter.

We have discussed metering at length on the list and it may be worth
your time to search the archives... it is a fascinating and complex
subject which unfortunately cannot be distilled down to a few sentences.
Photographers such as A. Adams developed entire systems of exposure and
development to work along side of specific metering techniques to
achieve their photographic objectives. He believed exclusively in spot
metering for reflectance, others use different methods. The only way to
discover which method is best for you is to read, experiment and learn
with reliable, consistent, accurate equipment.


Eric G.


------------------------------