Tim Hughes wrote:
"Does anybody know if the current cameras quote pixels in terms of RGB
pixels
or "full spectrum" pixels? Maybe current specs are for RGB pixels not
full spectrum."
To answer your question it is RGB pixels. Also please note that
professional quality digital cameras such as the Kodak DCS660 use a 3
chip CCD array. (a chip for each color} This is better for many
reasons. Of course all professional video cams also use a 3 ccd array.
One of the basic reasons for this is to avoid "pixel bleeding". If you
look closely at the images of cheaper ccd cameras both still and video
you will see this bleed. There is basically no way around it with a one
chip design. There are some studio ccd cameras that use a 3 shot method
with one ccd and a RGB filter. So it captures R, G, & B separately. The
quality of the images are quite good. However you certainly can not
shoot any movement any thing like that. It's not the size of the chip
nor the pixel density that produces good color. It's the quality of the
design of the ccd array. There are many other factors to consider such
as digital noise, power consumption and data transfer rates. Creating a
large ccd is really not that important. Right now the Kodak DCS660
(Nikon Body) or the DCS560 (Canon Body) can produce a 6 mega pixel image
from it's 3 ccd (3040x2008) design which comes out to a 18 mb file. Of
course this camera costs around $25,000. The reason it is so expensive
is not it's ccd size. It is it's ability to capture at a data rate
necessary to make this an effective tool for modern photography. It can
capture images at 1 frame per second with a 3 frame burst rate. The
electronics & power requirements design along with the features required
make this an expensive device to manufacture. As the image capture area
enlarges the problem of data transfer rates become a serious issue along
with reasonable portable power requirements. It is the opinion of most
industry observers that these data transfer rates & power requirements
will determine the design of the ccd array and capture size area.
Certainly as we see improvements is wafer manufacturing we will see more
dense and powerful chips, not bigger chips. Larger & faster data buses
along with lowered power requirements due to the smaller more dense
chips will be the solution for newer ccd cameras. Bigger sized chips
would be going backwards. So waiting for a chip size that would be equal
in physical size to a 35 mm image area may not be the future of hand
help ccd cameras. Some experts feel that lens design will eventually
change to take on this new format. So who knows? Olympus may redesign
a series of lenses to accommodate a standard sized ccd array when a
standard becomes a reality. Right now I think the industry is at a
cross roads where the analog standards are starting to give way to
digital standards ( which basically says smaller is better and less
power requirements equal faster performance). Performance is Everything
not old standards. Why use a new modern tool if it can't perform as
good as the older tool?
Phillip Franklin
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|