Digital BW, The Print

Jim,

> Actually you're both wrong, see:
>
> http://www.normankoren.com/Tutorials/MTF.html
>
> Quoting:
>
> The D60 has 72% the total resolution of full frame
> 35mm Provia scanned at 4000 dpi.

I skimmed over the link you provided, and I don't see anything I've said
that is in conflict with what that article says...it only talks about
MTFs...you apparently were referring to this link:

http://www.normankoren.com/Tutorials/MTF7.html

I design digital imaging equipment, and have been doing so for over 20
years.  I know intimately how digital cameras work, and what they are
capable of.

Your statement above, and the source you quoted it from, is simply wrong and
misleading.  The sensor used in the D60 uses what is called a "Bayer"
pattern, which means it uses a quad (four) sensor grouping of RGBG (One red,
one blue and two green, extra green for increased contrast).  The data from
these sensors is interpolated.  What this means is you do not get 6M REAL
pixels from the camera, you get 6M INTERPOLATED pixels from the camera.  The
camera has 6M SENSORS, NOT 6M PIXELS.  Interpolation basically means the
data is "derived"...as in not in the original image in the first place.

Film does not have this issue, as film has all three colors available at
point on the film.

Here are the FACTS for a legitimate image capture medium comparison, not a
processed image comparison:

The Canon D60 image SENSOR has 3072 x 2048 SENSORS.  That means 1.5M Red
sensors, 1.5M Blue sensors and 3M Green sensors, and therefore 1.5M Red
"data", 1.5M Blue "data" and 3M Green "data".  If the data is 8 bits, let's
say for arguments sake, that's 6M BTYES.

35mm film scanned at 4000 SPI gives you 4000 x 6000 FULL COLOR PIXELS, or
24M Red "data", 24M Blue "data" and 24M green "data", that's 72M BYTES.

Hum.  You want to compare a device that gives you 6M BYTES of data with one
that gives you 72M BYTES of data, and believe their image "quality" is the
same?

> But perceived image quality may approach that of film
> because of the low noise-- the absence grain.

That is very true...but that is purely sharpness...not detail, and as I've
said, I can sharpen a film image, reducing the tonality, and get the same
results...but that isn't as true to the original scene accuracy.

Regards,

Austin