640hx480v, to conserve storage space [31]. The original image for Fig. 6 is in full color, requiring only 118 kBytes of digital 
storage space. This demonstrates the powerful image compression schemes employed, and the pressing need to minimize the 
amount of image data to be stored in cost-sensitive consumer applications. Such an electronic camera, currently available for $650, 
is considered to be sufficient for many computer applications, but also for journals and magazines, providing that the final full- 
resolution reproduction size does not exceed about 6 cm [32]. 
The large-scale replacement of conventional film-based still cameras by electronic cameras, is expected once higher resolution 
image sensors and higher-capacity storage media at a lower price are available. At the turn of the century, small and inexpensive 
HDTV color CCD image sensors will be available with about 2000hx1100v pixels, showing a resolution comparable to 
photographic film. Although the cost of such electronic photography systems will still be higher than that of conventional film- 
based cameras, it is expected that the added conveniences of higher sensitivity, immediate picture viewing, direct link to image 
processing and hard-copying on PCs, etc. will lead the customer to shift to electronic photography within the next 5-10 years. 
  
Fig. 6 : Black-and-white reproduction of a color image taken with a commercially available electronic still camera (Apple 
QuickTake [29]), which offers a resolution of 640hx480v pixels. The camera's built-in data compression reduces the 
amount of image data to just 118 kByte per color image. 
The situation is different in professional applications, where the advantages of electronic photography do already outweigh the cost 
considerations in many cases. All major manufacturers of professional photographic equipment, such as Kodak, Sony, Nikon, Fuji, 
Hasselblad, Sinar, etc. already offer electronic photography products. Image sensors with a minimum number of 1200hx1000h 
color pixels are employed, with sensitivities equivalent up to ISO 800/1600 film speed. This pixel number is barely sufficient for 
most applications. If affordable, high-resolution image sensors developed specifically for electronic photography applications will 
be employed [32]. A case in point is Kodak's recently demonstrated M6 CCD image sensor chip with 3kx2k color pixels on an area 
of 36x24 mm”, finding its way into professional studio and reporting cameras. This is an alternative to existing solutions 
employing scanning CCD line sensors, requiring tens of seconds for exposure. Most professional applications, such as in the 
graphics arts, publication and reporting work, catalogue photography, etc. call for such a high-resolution color image sensor, with a 
resolution of at least 2kx2k pixels digitized to 12 or 16 bits, capable of taking flash exposures (one-shot exposure instead of 
scanning), and mounted in a precision-engineered custom camera back taking suitable new lens systems [32]. Such a camera is still 
IAPRS, Vol. 30, Part 5W1, ISPRS Intercommission Workshop "From Pixels to Sequences", Zurich, March 22-24 1995 
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