More Photography Answers
Question Library
Ask a question about Photography
Volunteer
Experts of the Month
Expert Login
Awards
About Us
Tell friends
Link to Us
Disclaimer
|
| |
|
|
| |
| | | |
About Bob Todrick
Expertise
I can answer questions on most areas of photography. Though fine-art nudes is my main focus, I can, as well answer most questions dealing with darkroom processes (including many alternative processes).
My expertise does not include digital.
Experience
I have photographed since 1975. Among my clients have been a number of major retail department stores (the Bay, Eatons). I photographed for Canada's premier motorsports magazine for a number of years, and have done much portraiture and wedding photography.
In 1990 I gave up shooting professionally to concentrate on my fine-art work and have had numerous group and one person shows since.
Organizations
Co-founder of the Group of Several.
Publications
Numerous newspaper and print ads.
GRAPHIS photo annual.
| | |
| |
You are here: Experts > Arts/Humanities > Visual Arts > Photography > film
Expert: Bob Todrick
Date: 5/17/2006
Subject: film
Question
with film, icreasing development time: does what?
why do we agitate for only oart of the time during development?
the ASA rating means:.....
Answer
Increasing development time increases film density.
Increasing agitation increases contrast and grain.
ASA (American Standards Association) is an internationally agreed upon standard which tells how sensitive to light any given film will be. ASA is actually no longer used...the accepted terminology is ISO (International Standard for Organization)...same numbers, same ratings.
ISO, development time, agitation, etc are all optimized by the film company to ensure that a given emulsion (film) will give the best possible results when used as intended. All of these paramenters can be modified by the photographer (ie: changing the ISO to over or underexpose the image, over or underdevelop to modify the negative, or over or under agitate to change the contrast and grain structure) to obtain photographic effects other than intended for that particular film.
That is where 'the art' of photography takes over from the science.
Hope this helps.
Add to this Answer
Ask a Question
|
|
