Case Study—Two Dimensional Flat Art
A level lets you get the
subject and film plane perfectly parallel.
A copy stand makes it easy to move the camera up and down and arrange the lights.
If some lights are placed
too close, the light on flat art won't be as even as it would be were they placed farther away. The
Smith-Victor lights were amazingly uniform no more then one-tenth of a stop difference over the entire surface.
When copying documents, maps, or other flat subjects, one choice is to scan them on a flat bed scanner. If they are too large, or if you don't have a scanner, you can photograph them using a copy stand or equivalent setup. When doing so, you need to use even light, avoid reflections, and avoid keystoning.
The assignment is to photograph watercolors so they look as much like the originals as possible. We have to avoid keystoning and reflections and show true colors.
The camera is positioned over the art on a horizontal bar and facing straight down. A level is used to ensure that both the camera and table are level so there will be no keystoning— converging lines on opposite sides of the document. To reduce barrel distortion, the camera is raised some distance
above the art and a longer focal length is used. Because the image will be printed, a gray scale and a color chart are placed alongside the art to provide known colors for the printer to make adjustments from.
To get the most even light possible, two Smith-Victor lights are placed some distance back and shining down on the art at a 45 degree angle.
3. Camera Settings
To check exposure, we first placed a gray card where the art will be placed. With the camera set on manual exposure we took a picture and then checked the histogram to see if middle gray fell in the middle of the range. We then used the same exposure to photograph the art, checking that the
white areas stayed white. White balance is critical so we also photographed color cards and checked that we were capturing colors the way they look.
The setup uses two Smith-Victor lights set
back and at a 45 degree angle to the art. The camera is positioned so it's centered over the art,parallel to it, and far enough away to avoid barrel distortion.
The final photograph shows the art almost exactly as it looks in the original. Colors are accurate and whites are neutral. Watercolor courtesy of Elaine Caliri Daly.
To photograph large flat art, you can hang it on the wall and light it from both sides.