Environment Scanner #2

Environment Scanner Version 2

Scanner #2

Scanner #2 was the first color scanner to have dichroic beamsplitters. I had a dichroic prism left over from an old Ampex color studio camera. I had come across some fairly sensitive PIN diode sensors at the TRW Swapmeet in El Segundo, and so I had coupled them to the dichroics.

I made some test scans. The diodes were really blind. I had to crank up the gain of my amplifiers to something like 10 million, and even then, I could only make images outside. Light leaks in the original box were a problem, as was the black paint I used. Some of the black spray paint got on the high-gain amplifier board, and it had never occurred to me it would be conductive... Major setback time while the PC board was rebuilt.

Here is one of the first color scans from Scanner #2. It was taken in my driveway in Chatsworth, California on a sunny day in 1986. You can see some artifacts from a light leak in some of the shadows. You have to bear in mind that the left side of the picture matches exactly with the right side of the picture to make a 360 degree pan. The car on the left is facing the garage door on the right.

By now, I had moved on to a front-surface mirror, and I was using a color-corrected lens from an old Graflex camera. This let me adjust the lens aperture. I could only make images outside, which was a step backwards, but they were in color. I did have a nasty time until I figured out I needed to filter out IR and UV from the light entering the beamsplitter. Otherwise, I got really strange images. You don't realize how much IR and UV radiation there is, and how narrow the spectrum we call "visible light" really is.

Here is a later scan of my backyard in Chatsworth . I could only move the camera about 50 feet away from the electronics, that's all the wire I had. So I stuffed the cables through my dryer vent and made a picture of myself at about 5pm in the afternoon.

The results from scanner #2 were encouraging, but I missed the sensitivity of the photomultiplier. So, I left scanner #2 intact, and started building Scanner #3.

Here is a scan taken recently with Scanner #2 in my back yard in Kingsport.