Digital film speed plays a mighty important role in achieving professional looking photographs.
The wrong digital film speed can totally ruin an otherwise perfectly good shot.
There are three interdependent variables in digital photography.
Throughout the pages of this site I talk about how these three interrelate. For now just remember each will affect the other two. When you understand and find the correct balance of your shutter speed, aperture and digital film speed, your snapshots will transform into photographs.
Most teachers of photography start by explaining shutter speed and aperture.
I choose not. I start with digital film speed.
In the olden days of the 20th century when everyone shot with film cameras, film speed was unadjustable as you shoot. Once loaded into your camera it was no longer a variable to be considered.
When you load your camera with film of a given speed you are stuck with that speed until you either run out of film or waste the remainder and put in a new roll.
All you had to know about film speed is fast film equals fast subject, slow film equals slow subject. And that the faster the film the more noise in your photos. So, you load film according to what you intend to shoot. Then you shoot.
I love film photography. It is beautiful. It is art. It is very worthwhile. Yet I choose digital.
Digital film speed is to be considered with each and every picture you take. It can change with each shot.
When you are shooting with digital
film speed is a much more integral part of your basic camera settings. For example let’s say you’re sitting there minding your own business, shooting a pretty little flower.
Well, odds are you are using a wide open aperture and a film speed of 100 ISO for absolute clarity of a 16”X20” framed photograph. (Just for the record, that is a slow digital film speed)
Suddenly you look and see a Great Blue Heron. He is a little figedy and you just know he is about to take flight. Well 100 ISO film speed will never do!
You know full well that if you bother to shoot him at that film speed he’ll be all over the frame and just be one big blur. “Oh, My!” You exclaim. “What ever shall I do?”
Well, lucky for you, you are a regular reader of my site. So, you are very familiar with the quick change digital film speed built into your camera and in less than a second you are set to 600 ISO and pointing directly toward this majestic creature.
As he takes flight you click away at 5 frames per second. Because in that same split instant you knew enough to also set your camera to “Continuous” mode for both your shutter and your focus.
Lucky you, you end up with a whole series of Great Blue Heron flight shots from which to choose!
Now you happily go back to your flowers who have been ever so patiently awaiting your sweet return.
Digital film speed is important and…
it is pretty easy to remember. Fast film speed for fast moving subjects. Slow film speed for - - - well I think you get it.
One thing to keep in mind is that as you increase film speed the quality of your prints decreases. That's why you don't permanently leave your camera set on a high film speed.
You can change your digital film speed before each time you press the shutter release button. This means you can get a wide variety of types of photographs just by changing a setting or two. Isn’t digital great!?
Shutter speed is important because…
a fast shutter speed allows you to shoot a moving subject and get a crisp picture. Film speed, at crucial times, allows you to use a higher shutter speed.
I am starting with film speed because once I have my basic camera settings I find I change film speed more frequently than the other two. (Aperture & Shutter Speed)
Take a look at these two pictures.
I went to the extreme with these two pictures to make my point. Notice the first picture has bright color and nice tone quality. The second picture is very grainy and lacks bright colors and clarity.
The first picture was taken at a film speed of 100 ISO. For our purposes, ASA is the same thing as ISO. The second picture was taken at about 1600 ISO. Both pictures are drastically enlarged to show the difference.
The purpose of this demonstration is to say that if all your pictures are going to be printed at 4”X6” your film speed will make very little, if any, difference.
However, if you ever want to enlarge your shots or if you choose to crop a picture you will see a difference in the finish picture depending upon the film speed you use.
"Digital Film Speed" is 2 pages.