TIME-LAPSE NOTES Here are some key points to keep in mind when comparing film, digital, and video-based Time-Lapse Photography Systems: 1. Resolution and Optics: 35mm film is by far the higher resolution medium. ASA100 speed slide film is rated at approximately 16 million pixels. Digital and video systems run between .5 and 3 million pixels, with the 3 million pixel digital system costing $25,000 and the BetaSP video (which is the closest to film) costing approximately $50000 for the camera alone. Digital and video systems do not accommodate wide angle lenses. Their ranges extend to approximately 62°, while we regularly install systems with a 20mm lens which offers a 94° view. This is especially important on projects where an extreme vertical or horizontal view is required. Also, we use top-of-the-line Nikon Optics, not plastic. 2. Climate Control and Power Source: Our systems are designed to sit outside for years without any special climate control. A heating pad is desirable in the winter, but it is not required. All functions are controlled passively via the enclosure. Temperature range of operation is -20°F to+140°F. Digital and video systems are not designed to operate in extreme heat or cold, and in fact often fail in those circumstances. Our ATLS is completely internally powered by off-the-shelf batteries, with a change averaging every six months. Digital and video systems both require special power considerations, i.e., either direct electrical connection or special power packs with limited life. 3. State-of-the Art: We have had systems in continuous use since 1991. None have ever failed. The image quality has improved as film technology has improved. Battery life has been extended with the introduction of lithium batteries. You will be able to use these systems repeatedly for many years without fear of obsolescence. Digital and video state-of-the-art is about six months to a year, meaning that whatever you buy today (including the software) will be functionally useless in a few years. Remember, when you purchase a digital system, you are effectively purchasing a computer. You thereby aquire all of the support problems that go along with it. Support of our system is nominal. In addition, you need to consider archiving and formatting issues. The CD that you are using will probably be replaced by another format within the next 5 years. This means that you will need to rescan your archives. The quality and longevity of your archival files will be a direct product of your Original Source Image. Film will provide the best solution. 4. Legal Issues: Film has always been admissible in a court of law, but advances in computer technology have resulted in a real problem -for digital images in particular. There is, in effect, no original. With video, also, it is becoming impossible to determine what is "real" and what has been altered. Without an analog (film) original, digital and video images are less likely to be acceptable as proof-positive in a court of law.