[Leica] Digital vs. Film

["Anthony Atkielski" <anthony@atkielski.com>]

From: Neil Frankish <nfrnkish@dux4.tcd.ie>
Sent: Tuesday, October 12, 1999 11:40


> Are you referring to digital cameras, rather than negative scanners?

In that particular context, I was referring to CCDs.

CCD technology can meet and exceed the quality of film--at a price.
Unfortunately, achieving the same limits as those that theoretically apply to
film with a CCD is cost-prohibitive for just about everything except spy
satellites.  Achieving quality sufficient to replace film for _a specific
application_ can be much more economical, however.  It certainly is true for
consumer video, for example.

> He was of the opinion that further increases in CCD
> resolution were not possible without a quantum leap
> in technology ...

Within the context of digital photography, I agree.  Right now, nobody knows how
to economically produce a CCD chip that matches 35mm film in size (24x36 mm
imaging area), and unless something wonderful happens, it's hard to see how
anyone is going to find a solution to this problem any time soon.

> ... current densities are almost at the theoretical
> maximum - yet still can't match film resolution by a large
> margin.

This depends on what you mean.  CCD densities are very high, but they could be
made higher.  However, that's not the problem.  The problem is that the imaging
area is still too small.  You don't need a 6x4-millimeter imaging area with 200
million pixels; you need a 24x36-millimeter imaging area with 12 million pixels.
You need this because all existing 35-mm equipment is designed to work with a
24x36-mm area.  It's not economically wise to render all that equipment
obsolete, so you need to find a way to make CCDs that large.  Nobody has found a
way to do this yet, at least not affordably.  But the actual pixel density per
unit area is very high indeed.  If you could spread that over an entire 24x36-mm
surface, you'd have an incredible image.

Now, some would say that you can just build new camera systems designed for a
smaller imaging area.  However, that renders billions of bucks' worth of 35mm
equipment obsolete, and it also raises problems with things like
diffraction--and diffraction is one of those problems that cannot go away,
because it's a consequence of fundamental physics.  So the real success of
digital photography hinges in large part on a way of making CCDs as large as
35mm negatives.  I don't see that happening anytime soon.

> And this leaves out the whole question of data transfer
> rates of the much larger files that might be produced
> by a CCD-replacemant device.

Data transfer is not a problem.

The problems right now are affordable, 24x36-mm CCDs (they don't exist yet), and
compact, very-high-capacity data storage (which will exist in a few years).  The
first problem is going to be the limiting factor, unless, as you mention, some
sort of incredible breakthrough occurs (such a breakthrough, incidentally, would
revolutionize all of microelectronics, not just digital photography).

> Also, as a portable information storage device, film is hard to beat.

But it deteriorates and accumulates defects, making it a poor choice for
long-term archives.  Digital images do not have these problems.

> On the other hand, the pictures taken with the Leica S1
> digital camera are apparently of excellent resolution ...

Yes, but like all such high-end digital cameras, exposure times are unacceptably
slow (seconds).  No handheld candid shots are likely with these cameras any time
soon!

  -- Anthony