One of the things that I learned in my glass travels is that there are many things that can be done to glass after it is blown. There are all sorts of surface embellishments that are done "cold" that significantly enhance the piece. One of those techniques is sandblasting. The picture here shows a fairly complex sandblast process. I did this piece at The Studio at Corning Museum of Glass during a workshop on Photographic Processes in Glass.
This is a several step process. First, an image is prepared in Photoshop or some similar program. A half-tone screen is applied in Photoshop to break the image up into little dots, much like how a newspaper is printed. The image is inverted - blacks become whites and vice versa. This is printed on transparency film with as dense black ink as your ink jet printer can produce. This "negative" is then exposed on a photographic resist and washed out. Washing out the areas that were exposed to the light.
Once dry, this resist mask is glued to the glass to be sandblasted. On this piece, this was harder than it seemed as there were subtle compound curves in the glass that I blew. The "blank" was a base glass of black with an overlay of white. The overlay was pretty thin. The sandblasting cut through the white layer and exposed the black. I really went deep into the black to give texture. Note that there is one of the fish where the resist lifted and the sandblasting took out a portion of the white fish.
Sometimes "luck" happens. Once I got back from the workshop I started pricing out a good sandblast set up for use as home. This looked like it was going to be quite expensive. I then stumbled on an auction on eBay for a complete set up including the compressor (the most expensive part) that was fairly local. The seller was about 60 miles away and we could go pick it up - way too heavy to ship. I won the auction but had to go a little higher than I wanted - aren't auctions always that way? I now have a complete set up at home and have been learning to sandblast a little better.
