There are crystals that pass far infrared wavelengths. These
crystals, fashioned into lenses, have been used for many years to
determine the emissivity and reflectivity of many materials, as a
function of temperature, and angles of incidence. This has resulted
in the compilation of the characteristics of most materials. One
simply (!) needs to calibrate them with a high temperature black body
source and a responsive detector. Using this information, it should
be possible to construct infrared images that no current digital or
film camera can image. But not with photoshop, I suspect.
Roger
On 22 Feb 2009, at 11:04 AM, ADavidhazy wrote:
Let me add my $.02
Wavelengths beyond the red (at least for a while) are generally
called infrared
(or near infrared if close to the visible, like from 700 to 1000 nm
and far
infrared if above 1000 nm - I just made this up!) but anything that is
"imaged" by "thermal infrared" is essentially still infrared but it
should
be clearly labeled as such and not just be called infrared. Standard
digital
cameras, like film cameras, can't deal with thermal infrared since
the bodies
would become warm by the mere act of holding the camera body.
AFAIK "infra" simply implies beyond ... there are a lot of
wavelengths with special
names that are out there beyond infrared in all its manifestations.
Then there are the digital newcomers on the block that state they
can through
software make infrared images - no! if you don't record infrared in
a scene no
amount of software magic will include in the image any true
infrared. One can
guess but never be sure since we can't see it.
OTSOTM and JMO - ;) andy
