Lenses for Digital Professional Photography

Digital photography may be superior to conventional photography if the end-product is a printed image: digital photography is faster, cheaper for high photo quantities, it makes retouching easier, allows more effective manipulation and often has a higher quality. However, it makes much higher demands on the image reproduction quality of the lens because of the special technical requirements of the sensors (e.g. regular pixel grid, planar sensor surface and a 2 mm thick protective and filter glass plate in front of it) if the theoretically possible quality increase is to be realized in practice.

Lenses for adjustable technical cameras must offer really large image angles for perspective controls and lens swing and tilt and must ensure the very best imaging quality right up to their image circle margin. The resolving power and the contrast must be at their optimum even at high apertures (f-stop 8 to 11, when used with the relatively small area sensors even from 5.6) to ensure that diffraction and color noise do not impair sharpness.

Furthermore, the correction of curvature of field has to meet the highest demands because of the virtually perfectly planar sensor surface, and the lenses may not generate any color fringes or any visible distortion. All these demands are met by the Rodenstock Apo-Sironar digital, the Apo-Macro-Sironar digital and the Apo-Sironar digital HR lenses.

• Both lens series Apo-Sironar digital and Apo-Macro-Sironar digital (the latter is optimized for large scales) provide large image circles for use with digital scan backs as well as with chip backs having larger area sensors or being used in the macro-scan mode for larger formats by stitching multiple shots made with laterally shifted back from one shot to the next. So they allow substantial camera movements. Resolving power is designed for pixel grid widths down to 9 µm.

• The Apo-Sironar digital HR lenses provide extremely high resolution already from open aperture (optimum: f-stop 4 to 5.6), perfectly corrected image curvature and a correction for the thickness of the sensor’s protective glass. They are the best lenses for smaller sensors with pixel grid widths below 12 µm down to 5 µm.
  

More product information here via pdf-download:

• Apo-Sironar digital HR 28 mm f/4,5 (94 kb)
• Apo-Sironar digital 70 mm f/5,6 (93 kb)