# TIme Lapse Photography

This week’s math walk post got me thinking about taking pictures of math things that I encounter everyday, but don’t really think about.

You already know that I work at the Belin-Blank Center on The University of Iowa campus.  But, you probably didn’t know that my office is on the top floor of the Blank Honors Center and that I have a straight shot at the Chemistry Building right out my window.

The other morning I was looking out my window, thinking about my math walk, and feeling inspired about taking pictures when I saw a student rushing into the Chemistry Building at about 9:03 (probably late for a 9am class).

That got me thinking. . . .I wonder how many students walk into the Chemistry Building on any given day?  And, I wonder what the ebb and flow of students looks like?

So, I took my first stab at time lapse photography (TLP).  Now, the primary purpose of this TLP project wasn’t to be artistic.  In fact, if you’re looking for an artistic TLP project you should go here.  The point of this project was to answer my second question; What’s the ebb and flow of students like outside my window everyday?

I set up a camera (and by “I”, I mean I asked someone I work with to help . . .she ended up doing while I stood in her office and watched!)  and programmed it to start snapping photos at 7:45 am and stop taking photos 12 hours later.  The camera took a picture every 15 minutes.  And, this is what I got:

Next, I graphed the flow of student traffic, based on the pictures I had.  The graph looked like this:

Now, I’m wondering about quite a few things:

1. I wonder if I missed the busiest time of the day with my every 15 minute photo-shot?  It seems to me that at some point more than 18 students should be entering the Chemistry Building at one time.

2. What’s a good model for the data I collected?  Should I divide the graph into two (or more) separate parts . . .like day classes and evening classes?  Do I think these two times of day need to be modeled using two different equations?

3. Look at the shadows!  I wonder if I could try to plot the position of the sun or length of shadow vs. the time of day.

4. Given the structure of college courses I wonder how different the data would look if I collected data on a Monday or Wednesday?  Why might Friday not be a good data collection day?

What are some of the things you notice as you watch this TLP video?

Interested in creating your own?  I’d start here (actually, I did start there!).