Hello, .
Along with the aperture (f-stop), shutter speed is an
exposure component that deals with time.
Beyond controlling tonality (the brightness of our picture), it also records motion as blurred or static (not blurred).
If we intend to record something moving as static, then we need to use a shutter speed that's fast enough to do that.
Let's imagine making a photograph.
By the way, when we imagine making a photograph like we're about to do, this is an excellent way of studying and practicing photography
without our cameras.
Imagine we're standing on a sidewalk during the day with our backs against a building, facing out toward the street, and we've got the expanse of the sidewalk between us and the street.
The sidewalk has a consistent flow of pedestrians. Still, it's not so crowded that we can't see a steady flow of bicycles and cars moving on the street.
Also, in our picture are things that ain't moving; let's say those things are a mailbox, a fire hydrant, and the lower portion of a street light post.
For this specific photograph, our primary compositional consideration is to record motion as blurred.
Imagine using a 28mm focal length lens; our ISO is 400, and our
exposure is f-8 a 1/30.
We make the picture.
And now, take a few seconds and list the things you imagine blurring from the most blurry to the least blurry.
I imagined cars, bicycles, pedestrians, and things
that weren't moving.
But what if we wanted to make a picture that recorded the motion of the cars as static?
In that case, we'd need a much faster shutter speed and everything moving slower than the cars would record as static.
Using a faster shutter speed means we'd be decreasing exposure, which would make our tonality darker; so, to compensate for the loss of tonality we'd need to achieve an equivalent tonality by increasing the exposure with our aperture or the light sensitivity of our ISO, or both to equal the same number of stops of tonality that we lost by making our shutter speed faster.
Doing that would affect the depth of field (aperture) noise (ISO).
Specifically, we'd effectively have a shallower depth of field with more noise, or if we could use a combination of both aperture and ISO to achieve an equivalent tonality, we'd get both a greater depth of field and more noise.
As a side note, the technique of achieving equivalent tonalities is covered during the Introduction To Photography class or can be taught during Private Lessons.
The question becomes, how much speed do we need to record the motion of something as static?
Well, that depends.
Using the example above.
We don't need to use the same shutter speed we'd use to record the motion of a car moving at 30 to record the motion of a human walking at 5 miles per hour as static.
Doing so would either get us a shallower depth of field than we'd prefer, more noise than we'd prefer, or both visual outcomes if we used each variable.
I hope you're making pictures and you like them.
A lot.
I've got some classes scheduled.
The ways to study and practice photography with me are below.
Call me if you need help determining the best course of study and practice.
I'll help you be a better photographer—study and practice photography with me.
Currently scheduled classes are below.
Smaller classes mean better learning, so class sizes are limited to 5 participants plus me.
But smaller classes also mean spots fill up quicker, so sign up soon.
And what if the timing doesn't work for you in any of my scheduled group classes? Private in-person or online lessons suited to
your schedule are always an option.
And remember, we learn and improve by doing, so practice making at least one picture daily.
That's all for now; thanks for reading!
Sam