MarkBarbieri
Semi-retired
- Joined
- Aug 20, 2006
- Messages
- 6,172
I'm working on a project and I need something that moves at a relatively constant rate that isn't too fast or too slow.
Here's my project. I want to set up a scene. I want to photograph it with ISO 100, 200, 400, 800, 1600, 3200, with shutter speeds of 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1, and with apertures f/22, f/16, f/11, f/8, f/5.6, f/4, f/2.8, and f/2. That's 6 ISOs, 10 shutter speeds, and 8 apertures, for a total of 480 different photos (one for each combination of settings).
Why? To help people understand exposure better. I'll post all the pictures online and have a web page that makes it easy to compare two pictures with different settings. To show people the effect of aperture on DOF, I'll have near, middle, and far objects along with a ruler. To show people the limits of dynamic range, I'll have a white textured paper towel and a black textured strap. They'll be able to see the how noise increases with ISO. Most importantly, they'll be able to see how changing one setting requires them to change another to keep the same exposure level.
The one thing that I want to demonstrate that I haven't got a subject for is motion. I want something that moves fast enough to be extremely blurry in a 1 second shot and frozen in a 1/500 second shot. I tried a fan, but it moves too fast. What's small and cheap and moves quickly enough but not too quickly?
Any other ideas on the subject are also welcome, but that's the big one that I'm struggling with.
Here's my project. I want to set up a scene. I want to photograph it with ISO 100, 200, 400, 800, 1600, 3200, with shutter speeds of 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1, and with apertures f/22, f/16, f/11, f/8, f/5.6, f/4, f/2.8, and f/2. That's 6 ISOs, 10 shutter speeds, and 8 apertures, for a total of 480 different photos (one for each combination of settings).
Why? To help people understand exposure better. I'll post all the pictures online and have a web page that makes it easy to compare two pictures with different settings. To show people the effect of aperture on DOF, I'll have near, middle, and far objects along with a ruler. To show people the limits of dynamic range, I'll have a white textured paper towel and a black textured strap. They'll be able to see the how noise increases with ISO. Most importantly, they'll be able to see how changing one setting requires them to change another to keep the same exposure level.
The one thing that I want to demonstrate that I haven't got a subject for is motion. I want something that moves fast enough to be extremely blurry in a 1 second shot and frozen in a 1/500 second shot. I tried a fan, but it moves too fast. What's small and cheap and moves quickly enough but not too quickly?
Any other ideas on the subject are also welcome, but that's the big one that I'm struggling with.

Newton's cradle, huh? I'm going to put that one in the memory bank for next time.
I didn't know what it was called either. So I googled "five metal ball on a string" you should have seen some of the responses I got
So I reworded it and google gave me Newton's Cradle.