Lens

First objectives for digital cameras were adapted to the CCD physical size. The lenses have to be very good quality because the real focus is much shorter as classical objective focus. In first digicams 7 mm real focus was used instead of classical 50 mm to cover the CCD surface. To satisfy user's requests very wide zoom range is used for digital cameras.
On example, 7.2-.50.8 mm (28-200 mm at 35 mm Leica format) zoom objective is used for Dimage 7. At so wide focus range, the spherical distortion and chromatic aberration should be visible, but for digital cameras the objective is created of so good quality that aberrations and other faults are reduced  to minimum. Exactly, barrel distortion by full wide angle on Dimage 7 is only 1,3 % .

The special focus length has some advantages for macro photography because the distance between lens and CCD is shorter. In this case, the ray's dispersion  makes depth of field as wider as appears by classical lens.