PC-SUPER-ANGULON 28 mm f/2.8 User Manual Schneider Optics Inc. 285 Oser Avenue Hauppauge · NY ¡¡788 · USA Phone 63¡.76¡.5000 Fax 63¡.76¡.5090 info@schneideroptics.com www.schneideroptics.
List of Contents Name of Parts and Cross Section of the Lens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Perspective Correction for Analog and Digital Photos . . . . . . . . . . . . . . . . . .
Name of Parts and Cross Section of the Lens Focusing ring PC-SUPER-ANGULON Distance scale Depth of field scale Aperture scale Aperture setting ring 1 1,25 1,5 2 3 5 0,3 0,35 0,4 0,5 0,7 1 3 22 16 8 4 2,8 4 5,6 8 Pre-set aperture setting lever Shifting knob Index Knurled ring Camera mount Fixing screw for camera mount
General Description The SCHNEIDER PC-SUPER-ANGULON 28 mm f/2.8 is a very high-quality wide-angle lens for 35 mm analog and digital SLR cameras and provides a parallel shift facility like the sliding lens panel of professional large-format cameras for correcting converging vertical lines and for manipulating the perspective especially for use in architectural and product photography.
Vertical shift is the most popular: upward, especially when photographing high buildings, so that the camera does not have to be tilted upward; and downward for product shots at an oblique angle or also for shots from high locations such as towers or mountains so that the camera does not have to be tilted downward.
Perspective Correction for Analog and Digital Photography The equalizing of converging lines or of unfavorable perspective due to a camera location made necessary by obstacles, reflections or danger, e.g. traffic, is not only interesting for conventional analog photography, but also for digital photography when higher quality demands are made.
es the sharpness, produces just visible bluish violet or reddish brown color fringes at edges which have been made perpendicular under fairly high enlargement and gives an image with incorrect proportions (width-to-height ratio). Since the final image must, however, be rectangular, the triangular areas projecting on two sides have to be cut off, which shows how many pixels, which are important for high resolution, are lost.
Large Image Circle for Lens Shifts up to 1¡ mm The PC-SUPER-ANGULON 28 mm f/2.8 already produces an exceptionally flattened image at full aperture within the 62 mm image circle which is thus twice as large in area relative to the image circles of other 35 mm lenses. Sharpness and contrast are increased further in the central area used without shift by stepping down slightly to f/4 to f/5.6.
entation can always be chosen, e. g. irrespective of the shift direction with the knob at the bottom with free hands, or rather at the top at the tripod. With a shift to the left or to the right, the shifting knob can always be at the left so that the right hand can hold the camera and remain on the release button. Natural size max. ¡¡ mm max. ¡0.5 mm max. 9.5 mm Imag e circle 44 mm Image c ircle 62 mm With a diagonal shift, the adjustment path should not go beyond the lock noticeable at 9.
¡0 Fixing and Removing the Lens The lens is available in a connection socket to match different 35 mm SLR camera systems and is inserted into the camera bayonet or thread for fastening to the camera such that the red dot on the connection socket is opposite the corresponding marking on the camera.
Parallel Shift The lens is shifted perpendicular to the optical axis relative to the bayonet mount and so also relative to the taking format by rotating a knurled shifting knob at a shaft which is elastically flexible to protect against its damage or injury to the user. The lens tube can be rotated continuously to the left or the right in a rotary mount so that the parallel shift can be made in any desired direction.
¡2 Focusing and Depth of Field The focusing of wide-angle lenses appears to be relatively non-critical due to their large depth of field. However, careful focusing is actually necessary to utilize the high imaging quality of this lens to the full. To ensure maximum brightness of the focusing screen and the best recognition of the ideal focusing point, the aperture should be opened by pivoting the stoppingdown lever toward the shifting knob.
Measuring the Exposure If the measurement is not carried out using a separate hand exposure meter, but using the TTL exposure meter integrated in the camera, it is necessary to measure in the centered position of the parallel shift while stopping down to the working aperture because the arrangement and alignment of the measuring cell of almost all SLR cameras requires a direction of light incidence axially symmetrically to the lens bayonet.
¡4 Filters, Lens Hood and Camera Mounts Only the oversized B+W WA filters of the size 67 EW can be used with the SCHNEIDER PC-SUPER-ANGULON 28 mm f/2.8 due to the extremely large image angle utilized at maximum shift up to 93.4°. The following table shows the order numbers of the most popular filter types – further types are available.
¡5 Wide-angle filters of size 67 EW Order no. B+W UV Filter with MRC coating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40295 B+W Skylight filter MRC coating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14386 B+W Käsemann linear polarizing filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75246 B+W Käsemann circular polarizing filter with MRC coating . . . . . .
¡6 Specifications Relative aperture . . . . . . . . . . . . . . . . . . . . . . . . . . ¡:2.8 Effective focal length . . . . . . . . . . . . . . . . . . . . . . 29.2 mm Nodal point separation HH' . . . . . . . . . . . . . . . 57.9 mm Optical design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ¡2 lenses in ¡0 groups Near distance correction . . . . . . . . . . . . . . . . . . Floating elements Image circle diameter . . . . . . . . .
