Re: [Leica] Future of film

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

From: Jonathan Borden <jborden@mediaone.net>
Sent: Tuesday, October 12, 1999 05:03
Subject: RE: [Leica] Future of film


> We now pay more for lower quality CD (despite the
> so-called higher signal-noise ratio), all in the name
> of higher profit for the distributer.

If you measure the actual extent to which the original recording is accurately
reproduced for the listener's ear from end to end of the recording and
reproduction chain, CDs blow vinyl phonograph records away.  There is no
comparison between the two at all.  This is one reason why CD wiped out
phonograph records: it allowed just about anyone with a cheap Discman to hear
music reproduced with fidelity that formerly required $15,000 worth of
specialized equipment.

> Society accepts this because CDs are more convenient than
> LPs and because most people don't take the time to notice
> the difference in quality.

The difference in quality favors CDs, under real-world conditions.  This is
always the case for digital representations, which is why they tend to replace
analog representations as soon as the technology allows it.

> Does anyone have a rough idea of how many grains of
> silver there are in a typical modern 100 ASA 35mm B&W
> negative?

Have you taken a lot of pictures in which the exposure levels of individual
grains of silver were essential to proper representation of your work?

If the smallest detail in a photograph exposes 25,000 silver grains, then the
exact number of grains in the negative doesn't matter, does it?

And if each grain were used to record important details of an image, then most
of your photos would be ruined, because the negative would not have exactly the
right number of grains in exactly the right place to properly record all the
image detail.

> Or alternatively given the MTF of such a negative, optimally
> developed, how many CCD pixels would be needed to achieve a
> similar MTF?

Can you show me what percentage of real-world photography needs that maximum
theoretical MTF?  There must be a reason why everyone isn't shooting on Tech
Pan.

If you really need the answer, Tech Pan produces an image of about 23040x15360
pixels.  This can be achieved digitally, but only in studios and in other
special situations.  It also requires a lens that can resolve 320 line pairs per
millimeter, and there aren't too many of those around (not even at Leica).
Finally, in order to actually see this level of detail in a finished print from
a viewing distance of, say, two feet, the print would have to be enlarged to 13
by 8 feet.  Most people don't look at billboards from 24 inches away.

  -- Anthony