Wednesday, May 13, 2009

When is a Picture Not a Photograph?

Okay, this shouldn't be too hard. Paintings can be pictures and they're certainly not photographs. The image that goes along with this post isn't a painting, drawing or sketch and wasn't taken using a camera. At least not one we typically think of as being a camera. It's a scanograph. It was "taken" using a scanner. It's easy enough to do. A scanner has a huge lens, short Depth of Field, and uses long exposures.

The image is made up of three scans, the flower, the fern (?) and the branch of buds. The three are then composited to create the composition. You really don't have to worry about crushing the flower because you can leave the top of the scanner off (or open). Due to the laws of physics we have the inverse square law about how light acts. (The amount of light that falls on a subject is inversely proportional to the square of the distance between the source and the subject.)

The source (light) is the lamp that transverses the scanner. The subject (the flower in this case) is sitting on the glass plate of the scanner, about one inch from the source. Therefore, with your scanner sitting on a table, or desk of almost any height, the amount of light hitting, even a white ceiling, is so ridiculously small as to eliminated. The white ceiling is rendered black.

The exposure is pretty much fixed. It's the amount of time it takes the lamp to traverse the scanner. Every portion of the subject will get the same illumination. Shadows, such as on the flower, come from the position of the light compared to the pedals of the flower. It's an interesting style of "photography" that's well worth exploring.