[Technical Info]

All these pictures were taken with digital scanning panoramic cameras that I made myself out of flatbed document scanners and old 35mm SLR lenses.    I also wrote the software that operates the cameras and some specialized image processing software to handle the rather unusual images they produce.   

A scanning digital camera takes images one narrow vertical line at a time.  Each line is really a separate photograph and there are thousands of lines in a picture.  That is a slow process, so scanning cameras are only good for stationary subjects under steady lighting.  

My panoramic cameras revolve around a vertical axis to scan an image of part of the world.  The scan can cover any angle up to 365 degrees.  The vertical extent of the image (which I also measure in degrees) is determined by the focal length of the lens and the length of the CCD image sensor.  These cameras can achieve very high resolution because the image sensors have large numbers of pixels, and because the whole  picture is taken on the lens centerline.  They produce seamless images with true panoramic perspectives: cylindrical if a "normal" lens is used, spherical (technically, equirectangular) with a "fisheye" lens.

My oldest camera is optimized for taking long panoramas at very high resolution.  It has a 10,600 pixel CCD 42mm long, which covers the full image circle of a standard 35mm lens, at a resolution that only high quality lenses can deliver -- equivalent to 48 megapixels per 35mm frame.  I use Asahi Takumar lenses of 55 and 28 mm focal length and a 16 mm Zenitar fisheye, which give image heights of 54, 75 and 150 degrees respectively.  I usually scan at 1/2 or 1/3 of the maximum resolution and record 50 to100 million pixel images, enough for about a square yard of sharp print.  Typical scan times are 5 to 15 minutes.

A second camera is optimized for speed with very wide angle lenses, from 8mm to 24mm focal length.  It has a 5,400 pixel CCD  28mm long -- a little more than the height of a 35mm film frame.   With a fisheye lens tilted up at a steep angle, it can capture images of tall buildings or the whole dome of the sky (such images need special processing to correct color registration errors due to the extreme scanning geometry).  A full circle scan with an 8mm lens has about 36 million pixels and typically takes 2 to 7 minutes depending on light level.  The 16mm lens delivers about 100 raw megapixels.  I usually convert these scans to circular views with about 2/3 as many pixels.

My latest camera is an all purpose compromise with a  5,300 pixel sensor 37mm long.  Its larger pixels give it somewhat better exposure latitude than its predecessors.  There is an article on that one here, and some engineering details on the older ones here.

I finish my pictures on a 2 GB PC using Photoshop , the Helmut Dersch panorama tools, and some  programs I wrote myself.   Because of the high pixel density, it is possible to alter viewing projections fairly radically and still have smooth, crisp images.  I often use projection functions custom made for the image at hand, especially for architectural subjects.  This is analogous to using the tilts and swings on a view camera, but more versatile, as one can get projections that no lens could produce.

I make prints on archival and fine art papers with  1440 DPI Epson printers using Ultrachrome inks.   To control color and tone rendition, I use input ICC profiles specific to  the camera and lighting conditions, and output profiles specific to the ink and paper.   Pixel density ranges from 40,000 per square inch in the largest prints, to around  300,000 per square inch (which is more than these printers can really render) in the smallest.   By comparison, you are probably viewing the images on this site at about 10,000 pixels per square inch.  

 Many of these pictures contain odd looking blips, often in primary colors.  That is how the scanning camera renders things that are moving horizontally  -- mainly people and vehicles.  Things get more compressed the faster they move.  The coloration is due to the fact that the red, green and blue images of a given point are scanned a fraction of a second apart.  I like the way these cameras change traffic from a major visual blemish to a sort of comical decoration (obvious in "Twilight Skyline", but try to find the two images of a moving car in "Morris Meadow").