cis vs ccd

  • Thread starter Thread starter Thomas Mann
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Which of these two scanner-technologies is better ?


CIS was developed for FAX machines and is implemented
these days also in some of the Canon LIDE flatbed
scanners. CIS is generally lower resolution than CCD,
but has the advantage of requiring no optics and thus
makes for a very thin and compact and potentially
cheap mechanism.

CIS doesn't sense color; to get color from CIS the
light source is cycled between the three additive
color primaries (R,G, B) on each scan line.

And then there are odd hybrids -- like the Nikon film
scanners that use a CIS illumination scheme with a
monochrome CCD sensor.


rafe b.
http://www.terrapinphoto.com
 
Raphael Bustin said:
CIS was developed for FAX machines and is implemented
these days also in some of the Canon LIDE flatbed
scanners. CIS is generally lower resolution than CCD,
but has the advantage of requiring no optics and thus
makes for a very thin and compact and potentially
cheap mechanism.

CIS doesn't sense color; to get color from CIS the
light source is cycled between the three additive
color primaries (R,G, B) on each scan line.

And then there are odd hybrids -- like the Nikon film
scanners that use a CIS illumination scheme with a
monochrome CCD sensor.


rafe b.
http://www.terrapinphoto.com


Canon has a CIS-Scanner with a very high resolution (2400 x 4800 dpi), so I
wonder why the CCD-Scanners are more expencive when there is no difference
in the scan-quality ?
 
Canon has a CIS-Scanner with a very high resolution (2400 x 4800 dpi), so I
wonder why the CCD-Scanners are more expencive when there is no difference
in the scan-quality ?


Which LIDE/CIS scanners get 2400 dpi?

I've searched for CIS assemblies and found
none above 1200 dpi. Granted, Canon may well
have their own proprietary models.

At 2400, they almost become useful as
scanning backs for LF cameras...


rafe b.
http://www.terrapinphoto.com
 
Canon has a CIS-Scanner with a very high resolution (2400 x 4800 dpi), so I
wonder why the CCD-Scanners are more expencive when there is no difference
in the scan-quality ?
Because there is a difference with scan quality. Don't confuse quality
with pixel count.
 
Because there is a difference with scan quality. Don't confuse quality
with pixel count.


What evidence do you have that CCD beats CIS, or
vice versa? Seriously...

It turns out (for example) that the Canon LIDE scanners
are excellent machines for making printer profiles, though
I think that has as much to do with the illumination as the
sensor.

PS: answered my own question earlier; the Canon
Lide 80 is 2400 dpi. Interesting...


rafe b.
http://www.terrapinphoto.com
 
Hecate said:
Because there is a difference with scan quality. Don't confuse quality
with pixel count.

--

Hecate
(e-mail address removed)
veni, vidi, reliqui


Is there really a difference in quality ? I mean, did you compared it by
yourself or read something about it ?
 
Is there really a difference in quality ? I mean, did you compared it by
yourself or read something about it ?
Reading and some comparison. Of course, what I said is a
generalisation and I come at it from the photographic side of things
where you can see definite differences in quality. I suspect that
continuous tone images are a problem but it may do OK for other types
of input.
 
I've had a Canon LiDE80 since March of this year (2004), and I have
found that you really have to put heavy objects evenly over the lid to
keep everything perfectly flat on the glass when you scan - otherwise,
everything will be blurry. I was unhappy with the quality in scanning
artwork of mine compared to the Microtek 9800xl scanners in the lab at
school, but Canon has since released updated drivers that seem to
improve the scan quality significantly. I am still unhappy with the
complete lack of DOF, but scans can become razor sharp with a little
high-pass in Photoshop. The main fault of this scanner is the lack of
support by Silverfast, but with the 9900f recently gaining support,
who knows...

Had I the opportunity to get a different scanner, I would, but for the
price and for what it is, it is an above-average product. It lacks a
transparency adapter, though, so keep that in mind.

-john
 
Which of these two scanner-technologies is better ?


CCD is better for most purposes. Charge Coupled Devices (CCDs) use a
PIN Photodiode with a lens for each color of each pixel.

CIS or Contact Image Sensor arrays are used where compactness and low
cost are the design criteria. They require more light and introduce
more noise ito the image, but don't require the deep chassis that the
CCD lens array requires.

Here is what Canon thinks of the CCDs:

http://consumer.usa.canon.com/ir/controller?act=CanonAdvantageTopicDtlAct&fcategoryid=104&id=6161
 
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