Shifting Sands

My photographic record of the changing sands of Back Beach

(Most recent updates)

My father and I regularly walk the dog on one of New Plymouth's great beaches. I especially like Back Beach. It's just out of the city and a little more rugged than the beaches to the north. New Plymouth is situated right under Mt Taranaki, a dormant volcano, and along the beach cliffs you can see how the land is made up of layers of old ash falls, sedimentary rocks and debris flows. All along the coastal cliffs, the surf is actively eroding these old volcanic rocks and while the beach is predominantly sandy (most of the time), you can observe a steady supply of rocks and coarse sand coming off the cliffs. We started making a point of noticing the changes on the beach each day and quickly realised that the changes were much quicker and more extensive than you might assume. Even if you're at the beach every day, you don't quite notice how much it changes over time unless you really look. Last year, I started taking a set of photos from the same spots on the beach each time we walked there. Unfortunately, before I could organise the photos I lost them all in a disk crash (yes, I make better backups now). As the weather has started to improve this year, I've restarted the project.

We choose a number of sites on the beach which we could reliably return to each time we visited. This is not an easy task as so much changes. Basically, we had to select rocks near the top of the beach which wouldn't move (often) and wouldn't be covered in sand at any stage. I hoped that taking the pictures from the same spot every time would allow me to compose a time lapse series of the beach. Once I had a decent number of photos, I tried lining them all up in Photoshop and quickly discovered how much difference a slight change in the angle of the camera can make. Fortunately, I found some panorama stitching software that I could fool into aligning a time series of photos. I'll post later on the software and how I used it.

Anyway, here are my first attempts. At this stage, each animation is made up of about 9 photos spread over about three weeks. As you will see in some places on the beach, more than 2 metres of sand has disappeared if just a few days. Imagine how many truck loads you need to do this manually! I've posted two versions of each series, one fast and one slow. Both pause at the end of the series before looping.

Currently, I'll post the photos as animated gifs and once the file sizes get out of hand, I'll encode them to some video format. These first attempts are pretty rough and represent my first attempts two weeks ago. I've refined my techniques quite a lot since them and I'll update regularly.

There are two versions of each series one with no delay between frames and one with a 0.5 second delay between frames. Each series pauses briefly at its end before looping.

• From the Stream looking north (slow frame rate)
• From the Stream looking north (fast frame rate)
• From the Stream looking south (slow frame rate)
• From the Stream looking south (fast frame rate)
• From the first 'bay' looking north (slow frame rate)
• From the first 'bay' looking north (fast frame rate)
• From past the first point looking South (slow frame rate)
• From past the first point looking South (fast frame rate)
• From above the rocky point looking north (slow frame rate)
• From above the rocky point looking north (fast frame rate)

Wednesday, October 31, 2007 in miscellaneous  | Permalink |  Comments (1)