Image of the Week - 21 October 2003

Canon 1Ds 15-Minute Exposure Test

The image is a test of the Canon 1Ds Digital SLR's noise characteristics on long exposure images. The exposure time for this frame was 15 minutes, and was captured in the Microscopy Suite's TEM room with all lights off and all doors shut (the room was dark to human eyes).
As evidenced by the image, the 1Ds has extremely low noise for a digital sensor, and likely the best long exposure performance of any digital camera available. Similar to other cameras, the 1Ds performs 'dark-frame subtraction' on exposures longer than 30 seconds. This method automatically captures a second, same-duration exposure with the shutter closed right after the primary exposure, and uses it to subtract the noise from the primary exposure.
The image was shot using the Canon 1Ds, 16-35mm @ 16mm, f/2.8, 899 sec., ISO 100, bulb exposure mode with a timed remote release. Raw converted with Adobe Raw Converter, with a slight levels and curves adjustment in Photoshop.

Image Courtesy: Benjamin Grosser, Imaging Technology Group

Contact: grosser@itg.uiuc.edu