V1.02
Thom Hogan’s Complete Guide to the Nikon D300
Page 34
the issue is essentially the same: just how good are pictures
you take with a D300 compared to those with a 35mm film
camera?
As I previously noted, on a pure pixel level 35mm film can
still win. Let’s look at the numbers more closely. The D300
generates a maximum of 4288 x 2848 pixel images with 14
bits of data per color channel. The Nikon Coolscan 5000,
generates 5782 x 3762 pixel images with 16 bits of color data
per channel from a full 35mm film frame (expensive drum
scanners generate even larger files). Thus, one would be
tempted to say that the D300 is, at best, slightly better than
half as good as 35mm film on a middle-of-the-line desktop
scanner (12 megapixels versus 21 megapixels, with only
seven-eighths the color information at any point). But that
wouldn’t be completely accurate
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.
Let’s try another way of looking at the issue. Most pros tend to
believe that the very best film can be scanned at up to about
4000 dpi. Anything less than that (say 3000 dpi) leaves a
small bit of detail behind; anything above that (e.g. 5000 dpi)
doesn’t resolve any additional detail. The long axis of the
D300’s sensing area is just a tad shy of an inch and it resolves
4288 points in that distance. In other words, the D300 is
working at somewhere around 4000 dpi at the sensor, or
about the same value you could get from film in that same
area scanned on the very best equipment available.
True, the 35mm frame has another half inch of width over the
digital sensor, but the cleanliness of the digital detail versus
the grain in the film detail makes things about a draw as far as
I’m concerned. I’ve heard people describe the D300’s
resolution as about 125% that of film, perceptually, and I’d
tend to agree it’s in that range.
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There’s also a school of thought—which I subscribe to—that believes that lack of
“noise” in an image is more important than additional resolution. Our eyes and
brains are very sensitive to “detail,” but false detail (noise) can be very distracting. To
demonstrate this in action, one only has to compare an enlargement from a scan of a
grainy film to one from a low-noise digital camera.
