[at-l] Slides

[gaudet@mediaone.net (Arthur Gaudet)]

This question got me curious enough to do a little research today. 
The following is largely from http://www.photo.net, a site started by 
the legendary Phil Greenspun, founder of ArsDigita. I've been able to 
back up most of what I learned with facts from the Kodak Reference 
Guide and Fuji Professional Dataguides, two books that I own. This 
stuff will help with people who want to do it themselves.

I thought of the general problem and looked for the particular 
details needed by professionals in order to make high quality 
pictures. The general problem is to go from slides, prints or 
negatives, TO slides, prints or negatives. Here are the answers, the 
first part talks about the choice of film for each situation, the 
second part talks about practical camera considerations.

Part I
 From original slides to duplicate slides: The industry uses a variety 
of professional films. The only one recommended for use in a camera 
is Kodak type SO-366. 3 other films are used in lab machines only.

 From original prints or artwork to slides: This is a common need in 
Art circles where slides are needed of oil paintings, watercolors, 
and other flat, well lit artwork in order to qualify for shows. The 
recommended film is Kodak EPN or Fuji Astia. Any other slide films 
will be too contrasty and will exaggerate colors. Both are readily 
available.

 From original slides to prints: This is the project I'm currently 
working on. Kodak 4325 or Fuji IT-N are recommended for 
professionals. Unfortunately both are only available in 100 foot 
rolls so I'm forced to buy enough for about 750 slides! Not sure what 
I'll end up doing.

 From original negatives to slides: As mentioned by another at-l er, 
Dale labs is a good source for this service. The type of film that 
they are probably using, called Kodak Vision stock film, is made for 
the movie industry. This film has some unique qualities that make it 
preferable for shooting over a wide variety of lighting conditions. 
This is the type of film that you buy when you buy from Seattle 
Filmworks. IMHO, the prints and slides that are created using Vision 
film are not very good. They would not be used by professionals, and 
many knowledgeable amateurs are disappointed in the results they get. 
But if you really need BOTH prints and slides, they are the only game 
in town. I don't know if Seattle is offering the same service that 
Dale labs, there might be others also who will take your regular 
negatives and make slides.

A recent post to photo.net talked specifically about the lifetime of 
Vision stock. It's likely that the negs and slides will degrade well 
before any of the other Kodak or Fuji products.

Part II
The second part of the task is to take the pictures (or have them 
shot for you). There are a variety of setups used to copy flatwork, 
one is known as a copy stand. There the artwork, print or slide is 
positioned in front of a stationary camera. For opaque items the 
lighting is brought in from the sides in order to avoid any hotspots. 
Flash can be used, but test shots might be needed. For transparencies 
the lighting is achieved through the material.

Camera optics must be set to have the exact magnification that the 
artwork requires. If you're shooting with a "through the lens" 
viewfinder you know exactly what's in the picture. Rangefinder 
cameras will have a parallax problem that make framing the picture 
more difficult. Point and shoot cameras cannot be used unless the 
artwork is pretty large, and at a distance that allows sharp focus, 
usually a minimum of 3 feet.

For my situation, going from slides to prints, I want the negative 
that I shoot to be exactly the same size as the slide. This means, 
optically, that I position the lens 2 focal lengths away from the 
film AND position the original slide exactly 2 focal lengths away 
from the lens. Since I have a bellows for my camera I can set this 
up, but labs (and some photographers) purchase a "slide duper" so all 
you do is attach the camera back to the device. It also handles 
illuminating the slide nicely.



>Let me start off by saying that the PA RUCK was
>awesome!  It was great to finally meet some of you
>that have been so helpful to us.  We particularly
>liked the slide shows, and JMT is definately in our
>future (2002?)  Anyway, I have a camera/film question.
>  How exactly do you go from film to slides?  Is there
>special film that you purchase?  Or a particular
>vendor that transfers film to slides?  We have an
>advantix camera.
>
-- 
Arthur D. Gaudet         	"Is walking down called hiking, too?"
(RockDancer)  	                 -heard at the top of Mt Washington, NH