Most digital artists use a stylus for input. Almost all of the applications use a non-intuitive color drawer to select a color for artwork. This design was inspired by work from MIT Media Lab’s I/O Brush.
The key idea of the prototype was to be as small as possible. We were using an LDR based system, that was calibrated to the light of different wavelengths illuminated by the pen. Once the illumination values were received by the LDR these values were re-calibrated to the selected color. The selected color was highlighted via an LED display on the top of the pen.
Individual LDRs had a different response rate for the same wavelength of light. This was potentially because LDR is not designed to capture wavelength information. We overcame this problem with individual calibration of LDR values. Another potential way was to use a better photo receptor for the prototype.
This prototype gives us a valuable tool to evaluate how digital artists use color drawers and to see if a natural color selection tool would fit into the toolkit of a digital artist.