First: The 10X refers to the zoom range, and has nothing to do
with magnification.
Second: The stated magnification is the ratio of focal lengths,
and not very intuitive regarding what you see.
To get the number takes a few steps in the table.
Step 1: find the CCD (object) size :1/2 inch for the KR222
Step 2: Pick a working distance, either 6" or 18"
Step 3: It is now down to three numbers, pick one: D(epth), H(ieght),
L(ength)
Step 4: The two numbers separated by ~, for example, 56.4~5.9(L) are
the fields of view in that dimension at minimum and maximum zoom range.
So for a KR222 at 6 " the field of view ranges (zooms)
from 7.9 X 5.9 mm to 74.6 X56.4 mm. (25.4 mm/inch)
An 8X6 mm (0.3 X 0.2) inch object will fill the screen
at full zoom. Actually, this number is what you need to know instead
of the magnification. What, you really want to know the magnication
anyway - OK -measure the object with a ruler, call this Obj; measure
the object on the screen call this Scr, divide Scr by Obj: Scr/Obj = magnification.
So 20/0.2 = about 100. Happy now?
Image quality will depend on the resolution of both the camera and the monitor (and, if used, the recorder) (oops, forgot - concrete floor and mounting stand at high mags). A small high resolution screen will look far more impressive than a larger low resolution screen, especially if your customer is standing close to the monitor.
To keep it simple I used the diagonal dimension for the screen;
therefore the magnification values are at best a rough estimate.
Using the aspect ratio and a bit of trigonometry the H and V dimensions
can be calculated. I prefer the Edison method (and I hold degrees
in Math and Physics). - take a ruler and measure your screen.
Edison story : hired a mathematician, and the first job he gave him was
to find the volume of a light bulb. Two weeks and many pages of triple
integrals later the mathematician reported that the bulb had a volume of
277.3 ml. Edison filled the bulb with water, poured it into a graduated
cylinder, and told the mathematician that he was off by 0.2.
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