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[OM] 1-hour vs pro photo processing; film reflectance

Subject: [OM] 1-hour vs pro photo processing; film reflectance
From: William Sommerwerck <williams@xxxxxxxxxx>
Date: Thu, 18 Feb 1999 06:46:22 -0800
"I was then recommended to a one hour processor in a nearby strip mall? and my
heart leapt to the skies never to return to the pro lab I used previously. I
specify the two day or three service and have not been disappointed yet.

"Am I alone or are the so called professional labs which charge premium prices
something of a con job? The young man who oversees the place I now frequent
tells me that the game is all in the printer person, the state of the art
equipment, the cleanliness of the chemicals, and whether the printer person can
imagine standing in the shoes of the photographer at the time the photo was
taken."


My prints are done by the one-hour lab at Costco in Kirkland, WA. The quality is
excellent, generally better than Kodak Premium. (By "quality," I mean whether
they get the density and color balance correct. Kodak Premium used to be
exceptional, but has badly declined in this part of the country.) Errors are
rare and slight, and are hardly ever bad enough to require a reprint (less than
1%).

The quality of their reprints, though, isn't excellent -- it's superb. I have
the manager do my reprints, and he consistently gets the density and color
balance absolutely dead-on. (In other words, his taste/judgement exactly matches
mine. This is important, too!)

When I first started using the Costco lab, I asked about their quality and the
manager told me how they did things, gave me a little "tour," showed me the
replenishment charts, etc. He told me in so many words that they cared about the
quality of their work. This is what you need to look for -- because (assuming
the lab has good equipment), "attitude" is all that matters.

By the way, Costco uses Fuji printers and Fuji print paper. Because I use Fuji
print film, it's possible I get somewhat better results than I would if I used
Kodak film. However, the Fuji printers seem to deliver sharper prints than even
the Kodak Premium printers.

Given the low price and high absolute quality of this Costco's work, I can't
imagine ever going to a "pro" lab.

>>>>>

"It is time there was a standard created regarding film reflectance!"

When OTF metering first appeared, Olympus said that films weren't identical, but
they were close to each other. (Note that the film's reflectance doesn't have to
be 18%, just that the camera be properly calibrated.) If most films used to be
18% reflective, it was a coincidence, because there is no theoretical or
practical reason why film reflectance should match average scene reflectance.

Gary Reese has measured film reflectance, and I have a question for him. As film
is exposed to light, the silver halide slowly breaks down into metallic silver
(or undergoes other chemical changes). (You can see the darkening this produces
by exposing the "tongue" to light for a while before loading the film.) This
change doesn't occur rapidly, but I was wondering whether Gary measures
reflectance "promptly" after pulling the film from the canister.

As for a "standard" -- it would be nice if film manufacturers spec'd the
reflectance relative to the Olympus calibration, but given the relatively small
percentage of OM cameras out there, it's unlikely they would ever see a need to
do so.


"Doesn't this also mean that when using a film that isn't 18% reflectance,
normal picture-taking speeds (which mostly use the shutter curtain pattern) will
meter accurately with available light, but long exposures (which are more
dominated by film reflectance) will have to be adjusted with the exposure
compensation dial? At what shutter speed does this start to become significant?"

Basically, yes. Let's "think, people." The shutter curtain opens fully in a bit
less than 1/60. When it is "half" open, the film reflectance will start to
dominate the exposure. Therefore, we can assume variations in reflectance will
start to have some effect at speeds below 1/125.

However, I think you're worrying too much about this. If correct exposure is
critical to you, you need to run a series of exposure tests regardless of the
make or model of camera you own. Very few cameras (if any) produce perfectly
accurate exposures for any and every film, over the full brightness range the
camera can meter. Only a series of exposures under widely varying lighting
conditions can show you how your camera behaves with that particular film. Film
reflectance is only one of the variables. There's little point in worrying about
it to the exclusion of all the other factors affecting exposure.



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