Vortex lamp with laser pointers and fog machine. The laser pointer is directed to the ceiling and is rapidly spinning in a circular motion, while fog/steam is blown underneath the lamp.
Our team (team Alpha) decided upon choosing the vortex laser lamp to photograph for this assignment. We set out to visualize the rapid, spinning motion of the laser pointer embedded within the lamp and photograph this phenomenon once fog is introduced into the mix. Unfortunately, we were unable to get the lamp to function properly with the fog inside of the machine. To counteract this, we removed the plastic covering in the front of the lamp and decided to use two small stage fog machines, courtesy of Professor Jean Hertzberg. Stephen Morton and I assembled the setup near Professor Hertzberg’s office in a lab workshop room and took photographs.
I was unsure of the specific type of flow motion we were experiencing until I did some research on laser behavior in various atmospheric conditions. The wavelength (or frequency) and intensity of the beam are significant characteristics, as well as the type and amount of impurities in the air. The beam must be of a wavelength that is visible to humans, and the fog must scatter the light very strongly so that you can see it. Since light can scatter from air molecules themselves via Rayleigh scattering, it is a powerful diagnostic tool for the study of gases and is particularly useful for aiding in the understanding of complex flow fields and combustion phenomena. Rayleigh scattering has a strong inverse dependence on wavelength, so it will be easier to see with a blue, and in our case, a green laser. As for the swirling fog that is seen under the laser lights, atmospheric turbulence plays a vital role in the formation and dissipation of fog, creating the cyclonic, smokey formations that we photographed.
The setup was a rather simple one. We placed the two fog machines at 45 degree angles facing the vortex laser lamp approximately 12 inches away. One fog machine was set on a continuous speed and one was set to emit fog at 3 second intervals or ‘bursts’. The entire setup was constructed on the ground underneath a table to eliminate any other light sources in the room and to isolate the turbulence of the fog. We snapped roughly thirty pictures or so, six inches from the turbulent, foggy laser light until we accumulated a decent-enough image. The images were captured under low-light conditions (in pitch black room), so the iso sensitivity of my Canon EOS Rebel t6i camera was set higher than normal, with a focal length of 18, exposure time of 1/30, F number at 3.5, and the dimensions at 6000 x 4000.
After photographing, I edited the image on my computer using Adobe Creative Cloud’s Lightroom. I tinkered with the exposure, highlights, shadows, blacks and whites, saturation, tint, and overall clarity of the image. I also decided to crop it and remove some background light the camera caught.
Comprehensively, I believe the photo came out well. The only critique I have for myself is that parts of the image are a bit grainy and harsh (in the top left corner), and some other sources of light and pieces of background are visible in the image that could have removed via blemish removal on Lightroom. Ultimately, I believe I have captured the motion of fog through a spinning laser vortex rather well, given how the lamp was half-functional, and the image is captivating, yet mystical.