RE: [Leica] Digilux 2

["Jay Burleson" <jayburleson@earthlink.net>]

Howard,
A 2/3 sensor is 8.8 x 6.6mm, with a diagonal of 11mm.

(below is copied from
http://www.dpreview.com/news/0210/02100402sensorsizes.asp)

"We regularly receive emails from readers confused as to the actual size of
sensor used in digital cameras. Sensors (CCD / CMOS) are often refered to
with an imperial fraction designation such as 1/1.8" or 2/3", this
measurement actually originates back in the 1950's and the time of Vidicon
tubes. Those who find the specification sheets for these sensors are then
even more confused about the relationship between the fraction and the
actual diagonal size of the sensor. Inside you'll find an explanation and a
table of common sensor sizes. We'll be adding this information to our
glossary for future reference.
It all started way back when...
The 'Type' designation given to toady's CCD sensors is that it harks back to
a set of standard sizes given to TV camera tubes in the 50's. These sizes
were typically 1/2", 2/3" etc. The size designation does not define the
diagonal of the sensor area but rather the outer diameter of the long glass
envelope of the tube. Engineers soon discovered that for various reasons the
usable area of this imaging plane was approximately two thirds of the
designated size. This designation has clearly stuck (although it should have
been thrown out long ago). There appears to be no specific mathematical
relationship between the diameter of the imaging circle and the sensor size,
although it is always roughly two thirds."

Read more at the link above.

Jay Burleson
“Every normal man must be tempted at times to spit on his hands, hoist the
black flag, and begin slitting throats.”
H. L. Mencken
 

- ---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.551 / Virus Database: 343 - Release Date: 12/11/03
 

- --
To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html