Optech Incorporatedintroduced theALTM Geminito its line of airborne laser terrain mappers. While maintaining the full performance characteristics of the ALTM 3100EA, the Gemini offers higher altitude operation at its peak repetition rates. A user can operate 100 kHz laser rep rates from altitudes up to 2 km, improving the survey efficiency of the ALTM by doubling the area coverage rate. Upgrades are available for older ALTM models. (Optech, Toronto, Ontario, Canada)