The Dot Line DL-DRF14/N Macro TTL Ringlight Flash provides full TTL control (including i-TTL) with both digital or film SLR cameras. This allows for accurate exposures of closeup subjects. When shooting at extremely short distances, relatively minor movement of lighting and subject results in relatively large changes of exposure. TTL metering eliminates the need for lengthy calculations of exposure, because the inherent loss of light at macro distances can automatically be accounted with ease.