The Canon MR-14EX Macrolite Ring Lite for close-up and macro shooting is loaded with features and capabilities. Now with Canon's E-TTL, it takes full advantage of the flash performance of the EOS-1v, EOS-3, and other E-TTL cameras. Circular twin flash tubes can fire at even power, or varied between them over a six-stop range, and one or more 580EX Speedlites can be used as wireless slaves along with the MR-14EX. The controller unit now has an illuminated full-info LCD panel and its accepts optional hi-capacity battery packs.