Bayer with NO anti-aliasing (Kodak Pro 14n)

For an example of a Bayer design that uses no anti-aliasing, people
should look at samples from the Kodak Pro 14n (nearly 14 megapixels).

http://www.kodak.com/global/en/professional/products/cameras/dcsPro14n/dcsPro14nIndex.jhtml
http://www.dpreview.com/reviews/kodakdcs14n/
http://www.steves-digicams.com/2003_reviews/dcspro14n.html

I think they look pretty darned good and definitely crisper than a
standard blurry Bayer, though not quite a match for Foveon sharpness
relative to the same screen area. Some subtle haze is added by the
Bayer interpolation, in my opinion.

The 14n has been around for many months but I thought it should be
mentioned as a example of Bayer at its finest. The sensor is actually
made by a company called FillFactory, and aside from not needing
anti-aliasing, it's also CMOS-based.

Apparently the 14n doesn't use anti-aliasing because the pixel array
is so large that moire patterns are usually "out-resolved," but not
entirely (see reviews). If it would only dispense with that RGB
interpolation there'd be "no moire worries!"

K2

 

Pretty crappy troll effort. I would say that the 14n is plagued with
problems.

If only is had a penis as big as the Sigma.

G

 

I guess anything could be called a troll, but my post was trying to
show a rare example of "pure" Bayer. Doctors recommend it, you know.

There are indeed some big noise problems with the 14n and Kodak says
it's best used for portraits with controlled lighting. Whether or not
the noise is just a CMOS issue or something else remains to be seen.

I have also stated that I'm no fan of Foveon's implementation in the
Sigma SLRs, or of any digital SLR because of dust issues.

K2

 

Godwin, Do you agree that its strange that some so called photographers
refer to the sex organs when talking about cameras. Giorgis is one seems
have difficulty in recognising the differences. Do you think he was
mistreated as a child by a photographer or perhaps he had his first orgasm
using a throwaway camera and has been trying to capture the magic moment by
talking dirty ever since.
MikeS

 

SNIP

Although I understand what you intend to say, the assumption not correct
because aliasing mirrors the unresolvable frequencies to lower frequencies
which are very easy to see.

Try a simple experiment. Using e.g. this file:
http://www.xs4all.nl/~bvdwolf/main/downloads/Rings.gif
it's a 1000x1000 pixel 1.21MB file with concentric sinusoidal waves, with an
increasing frequency towards the edges. View it at a 100% zoom setting in
your photoeditor. Downsample this to e.g.10% of its original dimensions
(100x100pixels), so your detail is 10 times smaller than your pixel
resolution. Aliasing in its extreme is the result.

You can use any resampling method you know of, Nearest Neighbor being the
sharpest and the worst and Lanczos windowed Sinc more accurate. Only
applying a little blur (similar to anti-aliasing or low-pass filtering)
before downsizing can reduce the artifacts. Try a Gaussian blur radius of
about 2 for the 10x reduction and compare. After resizing one should apply
USM or a similar sharpening to restore the finest frequency contrast.

I do agree that very small area aliasing is less likely to be visible
because of the large pixel dimensions, which don't need as much enlargement.
But large area aliasing will be painfully visible (try shooting regular
pattern subjects like flat cloth, with or without herring bone patterns).
And there is always detail smaller than the smallest sampling frequency
available in a sensor, all it takes is distance and a sharp lens (a poor
lens functions as a low-pass filter).

Bart

 

Bull. All sampled systems need anti-aliasing. It makes
no difference what the sampling rate is. Any frequency
component higher than 1/2 the sampling rate will cause
aliasing. It makes no difference if it's a Foveon or Bayer
sensor, and it makes no difference how many total pixels
there are in the sensor, or what their spatial density is.

Of course, at some point, the camera's lens will probably
perform all the band limiting that's required -- ie., when
the lens' resolving power itself guarantees the required
f/2 bandwidth limit.


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

 

PLONK

 

In message <>,

I looked at some of those samples, and they *do* have aliasing problems.
I see color artifacts on single, in-focus hairs against a dark
background, as well as stair-stepping in the more in-focus areas.
--

 

Although the 14n, with its 7.9 micron pixel pitch (or 127 lines/mm, or 63
lp/mm native luminance resolution) still requires a poor lens to do that.
IMHO a more efficient (only affects the highest frequencies) solution is a
good lens + anti-aliasing filter.

Bart

 

No comment on that! But I can tell that many people in this group are
extremely conservative about new technologies, Freudian motives or
not.

K2

 

So, I guess it offends you that I'm showing examples of something
non-Foveon that doesn't use anti-aliasing?

How about less plonking and more looking (with your eyes) at the
samples? Or are you afraid to learn anything new?

K2

 

What resolution is your monitor set to, what's the dot pitch and
what's the size? If you answered that in another post, forgive me for
repeating it.

K2

 

Amen. And the resolution setting of your monitor matters a lot, too.

Those people are obsessed with aliasing to the point that I don't
think they can enjoy the actual photos.

K2

 

What Bible did you pull that from? Why be so stuck on one idea?

Or when excellent monitor resolution renders it moot anyway. Printing
creates mechanical anti-aliasing as inks or dyes unavoidably bleed a
little. For that reason I would rather send an aliased image than a
pre-blurred one to a printer, since the printer will blur it enough.

K2

 

Whatever aliasing there is will be blurred away when printed on paper.
I just don't see it as a big deal.

K2

 

Yes indeed.

Ditto again. But the way you view an image (monitor resolution or
printer resolution) is a big part of the equation.

It's not I who disagrees on that point. Talk to these guys who claim
"all" form of digital capture needs anti-aliasing or it's somehow
violating an ethic.

K2

 

The 14n has, interestingly, the ability to sense 3.43M full color pixels
(the number of complete RGB sets). It is interpolated to 13.72MP, a lot
like another camera we know.

 

It's common knowledge for those who know what they're talking about. It is
also easy to see in unfiltered images. Discrete sampling results in visible
aliasing if significantly modulated frequencies exist above the Nyquist
limit.

Aliasing cannot be removed without removing detail. The anti-aliasing you
seem to be talking about is AA *created* by resampling for
printing/displaying at lower frequencies than present in the image. That
will only add aliasing, or at best not make it worse.

Bart

 

I believe I tried that, and the (maximum lossless compression) PNG came out
a little bigger, but anyway they're both tolerable sizes.

Bart

 

Jaggies is not a big deal if the pixels are small enough, but aliasing is.
Look at this example:
http://heim.ifi.uio.no/~asbjxrn/aliasing.png
(Crop from: http://www.pbase.com/image/23634928/original )

From what I can tell the effects are about 80 pixels high. And they
are visible for me until I's so far from the monitor that the two
rightmost lines merges into one. In photoshop not even a 5 pixel
gaussian blur will get rid of it.

What kind of printer do you have?
I got an i805 and actually did a A4 print of this picture (So I need a
life, what else is new.) and at the distance where the aliasing
"disappear" I am no longer able to see the circles... It's just a grey
square.