Making a repro backglass

20.4.2004:

The backglass is one of the most important parts of a pinball game, even though the action is on the playfield only. But the backglass graphics is an important element in creating the atmosphere for playing.

Pinball games missing a backglass, or having one with very flaky paint, are sometimes available very cheaply. No wonder, they are hard to sell without that important part. Maybe a spare glass could be found, after a lot of searching. But it costs a lot. Often old backglass is sold for hundreds of euros, or at the same price as a complete game. One begins to wonder if a backglass could be reproduced at a more reasonable price.

Only a few years ago, it would have been sheer utopy to think about making a silk-screened pinball backglass at home. But today, with digital imaging and printing, it is not impossible anymore. In principle it is very simple - just take a photograph of an existing glass and print that to some material transparent enough. But in practice, it is a bit more difficult. First, you must find the existing glass to be photographed, or get the pictures somewhere. The Internet brings pinball hobbyists closer together, and that makes finding the pictures a lot easier. And most print houses have a suitable printer for large printouts, so off we go!



Paragon without backglass.

This time, the situation was easy. We had bought two Paragons, one without backglass. But since the other had a good glass, no problem.

Photographing the backglass is not easy. You must get enough light onto the glass to take a god picture, but you must also avoid any reflections from lamps, camera equipment and the photographer himself. So it might take some time to find a suitable place and lightning. Finally one was found. Because the backglass is fairly large, even a 4-megapixel camera does not have enough resolution to get an image suitable for printing at on shot. The glass must be photographed in many parts, and the parts then combined.




The glass has been photographed in four sections.



Sections have been combined to one larger image.

Result is a large picture, that has over 100 dpi even when printed to 73 x 65 cm backglass size. Before printing, you can edit the picture to get all reflections and flaking parts fixed. For that, there are many suitable software programs. When you take the pictures, it is best to use the largest possible size your camera has, together with the lowest possible compressin. When you edit the image with your computer, do that with the uncompressed image so that its quality does not deteriorate in editing.

After the image is ready edited, and just the right shape, you can send it to print house to be printed. Now you should calculate the real resolution, or image pixels divided by its measurements. Inform the print house with all this data, image size in pixels, wanted printout size in millimeters (inches), and the calculated dpi (pixels per inch) value. This way you can be sure you will get the printout in correct size. From the printout, cut out the display windows with a carpet knife or razor blade. Here you can still do some little adjustments in case the printout is not of the very exact size. After that, attach the print to the backside of a 2-3 mm acrylic or glass sheet, to protect it from handling and UV-rays. This Paragon image was printed in two copies, one to the game and one to hang on the wall - Paul Faris art is sure good enough to display at your home.



A nice picture on the wall.



The other side of backglass.

The backglass image is transparent everywhere. But the original backglass has a silver mask, that prevents light shining through from the wrong places. In this way, certain parts of the graphics can be enhanced, and what's more important, backlit texts can be created such as GAME OVER or TILT. But compared to a game completely missing a backglass, it isn't a big deal if your selfmade backglass is missing the light mask. But you can make that from aluminum foil, or by photographing and printing. Many print houses can make a ready cut mask from a two-color picture. These are used in some commercials.

Some instructions on creating the light mask.

I have received many requests for the Paragon backglass image file, so in case someone still needs it, just download it from here :)

To get the image printed in right size, you need to tell the print shop the following numbers:
The image is 2995 x 2684 pixel.
Print width is 728 mm.
Print height is 653 mm.
Print resolution is about 105 dpi.
(One inch equals 25.4 mm)


Back