Improvements in the design procedure of apochromatic lenses are indicated and examplified with a design of a triplet derivative for long focal length reconnaissance. The main feature of the design is that complete correction of the secondary and residual spectrum has been achieved with the exclusive use of ordinary, large size, glasstypes. The correction of aberrations is virtually independent of wavelength and does not make use of aspheric surfaces. The barrel length is only 20% of the focal length. The maximum difference of the expansion coefficients of the glasstypes is 18X10-7/°C rather than 91X10-7/oC for a lens based on such exotic glasses as FK fifty and KzFS. Glass cost and delivery have gained similar improvements.