The Timelapse Project

Table Of Contents

1. Objective
2. Site Selection
3. System Specifications
4. Mounting the Camera
5. Weatherproofing the Camera
6. Network Topology
7. How It Works

Objective

The ultimate objective of this project is to create a timelapsed movie of the life of a tree over the course of a year. Hopefully, the project will run from January 1st 2006, until December 31st, 2006.

There are several other minor objectives, aside from the production of a movie:

• To create a timelapsed movie of a tree over the course of a year.
• To re-use as much computer equipment as possible. I don't want to spend any significant amounts of money on this project.
• To gather the daily images with as little human intervention as possible.

Site Selection

Of all the trees around my house, I really couldn't find a "perfect" tree, that met all of the following requirements:

• A deciduous tree, which is far more interesting to watch than an evergreen.
• A clean backdrop, such as the sky or a simple horizon.
• A safe place to mount the camera.
• A safe place to store the computer that is within about 10' from the camera (USB limitation) ^*
• A reliable and convenient power supply for the camera and computer.
• An out-of-the-way place, such that I wouldn't be capturing a lot of "junk" in the images, such as cars or people. Also, my wife didn't want to have to look at an ugly computer case and camera, so I had to keep it as discrete as possible.
• Easy access to my LAN, so that new images can be trivially copied to the web server, rather than mucking about with FTP or something similar.

^*Yes, I know I could have used a wireless webcam but one of the objectives of the project was to re-use as many old components as possible. Since I don't currently own a wireless webcam and I've got a better use for such a device should I ever acquire one, I constrained myself to a simple USB camera.

Eventually, I settled upon a location that meets most of the above requirements: It is located out of the house, in my workshop. There is electrical power, the workshop is locked and the contents are protected from the elements, it is out of the way (of both casual observers and my wife ;) ) and it is connected locally to my LAN, giving the imaging computer direct access to the web server for the purposes of publishing new images.

System Specifications

I tried to re-use as much old computer equipment as possible. The GeForce II graphics card is probably overkill, but recycling it into this project gave me an excuse to buy a new Radeon for my desktop computer ;) You can call it cheating if you want, but the motherboard built-in video was limited to 16-bit color - simply not good enough for a project such as this. And besides, I had a nice Sony 14" flat-panel with DVI connector that I simply had to use for something...

Mounting the Camera

The Camera is mounted to the back side of the garage, so it is not visible from the house or the street.

A simple "L" bracket is screwed to the wall, and serves both to mount the camera and the camera housing. The camera is attached to the "L" bracket with the top of an old mini-tripod. The legs of the tripod were removed and a hole was drilled through the head, so that it could be screwed to the "L" bracket. The camera is simply screwed to the tripod attachment.

You will notice that the camera is mounted upside-down. The only reason for this is one of convenience with a sprinkling of co-incidence. I was originally planning to mount the camera the right way up, but I couldn't get the camera housing to fit over it nicely. By simply inverting the camera, the "L" bracket can fix both the camera and the housing to the wall.

Fortunately, the excellent Willing Webcam software contains options to rotate and flip the image, so mounting the camera upside-down is not a problem at all.

The USB cable disappears out of a hole in the back of the case, through the garage wall and down to the computer, safely stored on the workbench. Notice how the cable (on both sides of the case hole) is routed downwards before connecting with the camera. This is so that any moisture that enters the case through the cable hole will run down the cable and drip off before going into the camera. Most people probably know this already, but I wanted to point it out as it is probably the most "professional" part of the whole thing.

Weatherproofing the Camera

In order for the camera to withstand a year outdoors in California's Central Valley, a certain amount of weatherproofing is necessary. While waterproofing the camera is obviously important, a greater concern is the ability of the camera to endure the heat of the summer sun. Temperatures in the valley have been known to reach 115°F (46°C) and can easily remain above 100°F for over a month.

The camera housing is actually a plastic cookie box from CostCo. In fact, if you look at the image to the left, you can clearly see the label for "Oatmeal Raisin Cookies" still on the front!

The transparent and waterproof cookie box is ideal for keeping the camera dry and the image quality is not noticably affected by the plastic in front of the lens. Furthermore, the lid can easily be removed for unrestricted access to the camera. However, as mentioned previously, the biggest problem I forsee is the heat in the summer.

To protect the camera from direct sunlight, the box is lined with a cardboard insulator. Actually, this cardboard serves an additional function in that it cuts down the reflections from behind the camera. Without this non-reflective screen behind the camera, there would likely be "ghost" images of the camera on all the pictures.

Unfortunately, I quickly learned that it is not enough to simply place the camera in a waterproof case - there must also be some way of keeping raindrops off the front of the camera, or else the resulting images are very poor. In an effort to keep water from collecting in front of the lens, I first coated the lid of the cookie box (in front of the camera) with a water-repelling Rain-Block solution. While this was somewhat effective, it still didn't alleviate the problem entirely - I needed to stop the rain from landing in front of the lens in the first place.

I quickly fashioned a "hood" out of - you guessed it - a CostCo cake container. My family don't usually eat loads of cake and cookies, but you have to remember, I started this right around Christmas time, so there was plenty of extra food around. And once the food was eaten, I was able to put the garbage to good use! Anyway, the hood is simply a cake lid with a hole cut out of the center and held onto the main camera housing with a bungee cord.

This arrangement allows the hood to be removed very easily and yet seems to be secure enough to withstand some quite strong winds.

Network Topology

Since the imaging computer and camera are located outside of the main network infrastructure (the wired LAN), the workshop must be connected to the house by a wireless network. This allows the computers in the workshop to have full access to resources on the local network as well as the internet.

Notice that the wireless link is only 802.11b, rather than the faster 802.11g. There is no real reason for this, other than the D-Link components I am using have worked flawlessly for several years and I really can't see a "need" for upgrading to wireless G. 802.11b is plenty fast enough for surfing the internet, listening to music and copying a few files from the imaging computer to the web server.

Occasionally the wireless link will fail and the images will not be copied to the web server. This usually happens during heavy rain and intense thunderstorms and is only a temporary hiccup. The imaging computer stores all the images locally, so I simply need to copy them manually (using a USB memory drive) on days where the link fails.

Also, the reason for a network hub in the workshop (rather than connecting the imaging computer directly to the bridge) is because there are other computers out there. I use the workshop to repair computers (spyware and virus removal, upgrades etc) and having a network connection available is very useful.

How It Works

Since the system only captures images for 1 minute every 24 hours, it made little sense to keep the computer running all the time. I was looking for a solution that would allow the computer to turn on, take the photographs, post them to the web server and then shut itself down.

The system that I used makes use of several technologies to accomplish this, from digital timer switches to batch scripts and a sprinkling of custom programming. The sequence of events is as follows:

1. At 11:50am, the Intermatic DT17 Digital Timer will activate, and the computer will switch on.
2. The computer will start up, automatically logon and execute two commands in the "Startup" folder:
   1. webcam.bat
      The batch file that converts the captured images to thumbnails, posts them to the web server and shuts the computer down after a specified time interval.
   2. Willing Webcam Lite
      The webcam software.
3. At 12:00, the webcam will capture 3 images, 5 minutes apart, and save them to the local disk.
4. After a 10 minute delay from the start of the batch script, the script will resume and create thumbnails of the captured images, copy the resulting directory structure to the web server then shutdown the computer. The computer is so old that it cannot actually shut down by itself - instead it displays a message that "it is now safe to switch off your computer".
5. at 12:10pm, the digital timer will deactivate, cutting power to the computer until 11:50am the next day.