AboutSara Bella Expertise I can answer questions about most anything photographic. From film to darkroom to digital photography, from lighting to Photoshop techniques to digital work flow. I also know a great deal about the historical and theoretical context of photography.
Experience I have been shooting photographs since I was 12. I have a BFA in photography and and I am currently working on my MFA. I am a photography teacher.
Education/Credentials BFA-photography
In residency to receive MFA in photography in 2008.
Expert: Sara Bella Date: 7/17/2007 Subject: Quick Question
Question Hello,
In order for me to produce a sharp image when I hand hold a camera with 100 mm lens, what shutter speed would you recommend?
Last question; When using an SLR what is the function of the automatic diaphragm? Any help with these questions would be greatly appreciated. Regards-Skyler
Answer Hello Skylar,
To produce a sharp image, I recommend that you use the fastest shutter speed that the light in the environment will allow. Also using a very small aperture will help you produce a very sharply focused image. You should take a light meter reading and then use the smallest aperture and fastest shutter speed possible that the light will allow in order to produce the sharpest image possible, regardless of the size of your lens.
What do you mean by "automatic diaphragm"? Do you mean the aperture? The aperture is not always automatic, and its purpose is to control the amount of light the film is exposed to, similarly to what shutter speed does. The larger the aperture is set (f/3.5 or f/2)the more light will hit the film. The smaller the aperture is set (f/22), the less light will hit the film.
In addition to controlling the amount of light hitting the film, the aperture helps you control the depth of field and focus in your image. The smallest possible aperture will help you produce a very very sharp image...where the foreground and background and midground are all in complete focus. Using the largest aperture will create an image where the subject is in fine focus, but everything in front of, and behind the subject is fuzzy. And I bet you can guess what a mid-size aperture does! It creates a mix between the super sharp, fine focus of f/22 and the fuzzy hazy depth of fieldy focus of f/2.
I really hope you meant aperture when you said automatic diaphragm...otherwise, please let me know what you were referring to.
