Dear Jim and All,
And don't forget that 'nits' have all the desirable properties of jargon, in
that they give a small group a buzz word that identifies the members of the
group as special (and therefore superior) to the rest of the population.
Cheers,
Pat Naughtin
CAMS - Certified Advanced Metrication Specialist
- United States Metric Association
ASM - Accredited Speaking Member
- National Speakers Association of Australia
Member, International Federation for Professional Speakers
--
on 2002/03/16 06.21, Jim Elwell at [EMAIL PROTECTED] wrote:
> Engineers who work with human-readable displays are familiar with the unit
> "nit", which is one candela per square meter (cd/m^2). It is used to
> specify how bright a display is (either directly for some types, or via
> backlighting for others). For example, a 150-nit display will be readable
> in roomlight, but washed out in sunlight, whereas a 600-nit display will be
> readable in sunlight, but too bright for viewing in a darkened room.
>
> The unit "nit" is used for two reasons: displays are a distributed light
> source rather than a point source (so lux is not appropriate), and, used
> properly, it is a photonic unit, which means it takes into account the
> response of the human eye.
>
> There clearly is no directly equivalent SI unit here, due to the photonic
> nature. But I think engineers use it for another reason: it is a short, one
> syllable word. It is a heck of a lot easier than saying "photonic-weighted
> candela per square meter."
>
> I bring this all up to make two points: (a) SI does *not* cover all
> necessary uses of measurement systems, so there are going to be new units
> "invented," although we hope they are based on SI (as nit is) and (b)
> people inherently like short words, which I think is one thing that turns
> people off about the metric system (e.g., inch vs. centimeter).
>
> I doubt anything can be done about (b), but I bet that words like "klick"
> (for kilometer) are not going to be eradicated even in all-metric countries.
>
> Jim Elwell
>
