The Promote Control Shutter Cable CN3 from Promote Systems is for use with the intuitive Promote Control which adds remote functionality to your digital SLR camera. It allows you to engage High Dynamic Range (HDR) photographs, time lapse sequences and more, quickly and easily.
Canon 10D, 20D, 5D Mk I, 1D/1Ds MkI and 1D/1Ds MkII cameras are not supported by the Promote Control HDR mode (with or without CN3 cable). Only a limited subset of basic features such as One-Shot, Time Lapse and Manual Hold are possible on these cameras, and would require a CN3 cable to be connected. The 1D Mark III, 1Ds Mark III, 5D Mark II, 30D, 40D, 50D cameras are fully compatible, including HDR mode.
On Canon 5D Mark II and 7D the longest automatic HDR exposure is limited to 30 seconds due to mechanical Bulb mode activation. A future Promote Control firmware update will prompt to activate Bulb mode manually as required. At this time using a higher ISO setting is recommended with Canon 5D Mark II and 7D if an exposure longer than 30 seconds is required in HDR mode.