FAQ sorted by alfabet
In this section the most common technical terms will be described. Select the first letter of the abbreviation or term you'd like to search for:A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z
DC
Sigma DC lenses only work on SLR’s with a reduced image circle, such as the Nikon D80 and the Canon 30D. Because there is less glass involved compared to full frame 35mm lenses they are cheaper to produce and they are weighing less.
DG
DG coating is an invention of Sigma that should reduce the reflections between the sensor and thus improve image quality. This has never been proved trough testing.
Di
Di coating is an invention of Tamron that should reduce the reflections between the sensor and thus improve image quality. This has never been proved trough testing.
DiII
Tamron DiII lenses only work on SLR’s with a reduced image circle, such as the Nikon D80 and the Canon 30D. Because there is less glass involved compared to full frame 35mm lenses they are cheaper to produce and they are weighing less.
DO
Canon uses it’s Diffractive Optics (DO) technology in their top of the line long telelenses. These elements use the principle of diffraction to change the direction of a lightwave’s path. The elements also correct for chromatic aberrations, even better than UD-elements, and provide correction like aspherical elements. The results of this technology are lighter and smaller lenses that still perform respectably. For further explanation you can read here: http://www.usa.canon.com/consumer/contr … mp;id=2632
DX
Nikon DX lenses only work on SLR’s with a reduced image circle, such as the D80 and the D200. Because there is less glass involved compared to full frame 35mm lenses they are cheaper to produce and they are weighing less.