Current webmaster: Shamim Pakzad (shamimp@ce.berkeley.edu).
CS 39J: The Art and Science of Photography is a freshman seminar taught
by Professor Brian A.
Barsky.
Site design by Steven Chan.
| CS 39J > Schedule & Notes > Session 3 Detailed Notes |
http://inst.eecs.berkeley.edu/~cs39j/fa04/session03.html
Notes from September 17:
Slide Film
Why use slides?
•Slides tend to be used a lot for photojournalism. They are useful because
you can look at them on a light table and project them up for everyone to see.
Being able to project your pictures in large format makes slides a great way
to show off your work.
Slides work differently than negative film, requiring different steps:
•One downside of using slide reversal film as opposed to negative film
is that you lose a step in the developing process and thus have one less opportunity
to correct mistakes. With negative film, you have to make a print from your
negative, during which time you can alter contrast, adjust exposure, and burn
and dodge problem areas.
•However, it is possible to make a print from a slide, but it requires
an intermediary step. You must make a negative from the slide called an intermediary
negative and then make your print from this. An important thing to keep in mind
is that anytime you add an extra step, you lose a bit of quality.
B&W and Color Slides use opposite rules of thumb for exposure:
•With black and white film, it is best to error on the side of overexposing
because then you know that the details are on the negative, you just have to
lighten the print. It is harder to correct the reverse problem of underexposing.
When you underexpose and then try to expose your print longer in the darkroom,
this can make your print grainier.
•With color slide film, you want to error on the side of underexposing.
This can actually deepen the colors and make them more rich. Overexposing can
lead to a whitened, washed out look.
Bracketing:
•Bracketing is when you take a series of the same photograph with a range
of different exposures, by either changing the aperture or shutter speed. This
is what you will be doing for your sunset assignment this week.
General Rule of Thumb for Exposure in Black & White Photography:
•Expose for the shadows, develop for the highlights.
General Rule of Thumb for Exposure of Slides
•Expose for the highlights (meaning underexpose slightly).
Practicality/Selecting Film
•Kodochrome is the original slide film, made by Kodak. It produces very
warm, rich colors and thus was the leading slide film for some time. The problem
with Kodochrome is that it’s not very convenient. Labs have to ship it
off to Kodak to be developed, which can be expensive.
•Other slide films use a process called E6 that is available even at 1-hour
places. The original film that could be processed using E6 was Ectochrome, also
a Kodak film, but the color was different. It had a much more blue tone than
the Kodochrome.
•Fuji then came into the market on slide film and noticed that people
like colors that are even more vivid than life. They created Velvia (ISO 50
and 100) and Provia (ISO 400). These are so-called professional slide films
with rich colors without the hassle of Kodochrome. Velvia is usually $6-$8 retail
and Provia is approximately $12 retail, though they can be bought much less
expensively from bulk retailers. Check out Photography magazines for ads.
•Kodak then stepped up their market to be competitive with Fuji and improved
their Ectochrome line. Ectochrome now comes in a variety of saturations like
Warm Saturated and Very Saturated for example.
Pushing Film:
•Pushing film is when you set your camera to shoot film at a faster ISO
that it really is and have the film developed as if it is that ISO. You lose
some quality and increase contrast by doing this, but it allows you to shoot
at higher ISO’s.
This week’s assignment:
•For this week’s assignment, you can use color slide film, Black
& White film, or even a digital camera. Post 4-5 pictures on your Unix account
for us to add to the website.
*If you have access to a darkroom, Professor Barsky highly recommends doing
some Black and White photography. Even sunsets can be great in Black and White.
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