Re: Fwd:

[al <nissar@xxxxxxx>]

A curious response to that is all the new media hype about that silly sony
camera, i think they sold another 20,000 at least since it was announced. I
can't imagine them getting anything but a vague heat based silhoutte.
Anyone else have any ideas on it.  Other than creating about 20,000 IR
wanna be's over night, hehe, it was an amusing on cnn. 


al



At 05:30 PM 8/19/98 -0400, you wrote:
>Helmut Faugel TE wrote:
>> 
>> On Tue, 18 Aug 1998, George L Smyth wrote:
>> > I rather doubt that the images would impart anything special.  I would
imagine
>> > that the boiler would not be as hot as a soldering iron, so it will
not emit
>> > infrared radiation in the recordable range.
>> 
>> If I remeber it in the right way IR-film can only record thermal radiation
>> form objects which are hotter than 400 degree Celsius. In G. Spitzings
>> book about IR-photography there is picture of a soldering iron recorded
>> on Ektachrome IR with a lens stopped down to f/5.6 and some (10 ?) minutes
>> exposure time in total darkness. So even if your object is very hot it
>> take a long time to record a picture, and it is nearly impossible to derive
>> the surface temperature from such a picture.
>
>Actually, the temperature is 250C.  At 500C the object will become
self-luminous
>and recordable with normal panchromatic film.  The belief that infrared
film can
>record heat is only partially true - it can if hot enough, as noted in the
>soldering iron reference.  However, magazines like Shutterbug that make the
>claim that heat from a person's body can be recoeded with IR film merely
>perpetuates the half-understood myth.
>
>george
>
>-- 
>
>Handmade Photographic Images
>http://www2.ari.net/glsmyth/
>*
>****
>*******
>******************************************************
>*  To remove yourself from this list, send:          *
>*         UNSUBSCRIBE INFRARED                       *
>*       to                                           *
>*         MAJORDOMO@xxxxx                            *
>*----------------------------------------------------*
>*   For the IR-FAQ, IR-Gallery and heaps of links:   *
>*  http://www.a1.nl/phomepag/markerink/mainpage.htm  *
>******************************************************
>
>

*
****
*******
******************************************************
*  To remove yourself from this list, send:          *
*         UNSUBSCRIBE INFRARED                       *
*       to                                           *
*         MAJORDOMO@xxxxx                            *
*----------------------------------------------------*
*   For the IR-FAQ, IR-Gallery and heaps of links:   *
*  http://www.a1.nl/phomepag/markerink/mainpage.htm  *
******************************************************

------------------------------

End of Infrared-Digest V0 #741
******************************