Using The Preview Buttons - Epson Expression 1680 Reference Manual

Note:
The luminosity value is calculated by the following formula:
0.2R+0.6G+0.2B.
For more information on the Pixel Depth setting, see "Image Type
button" on page 2-6.
Specifying the number of pixels to be sampled
You can choose to sample one pixel at a time, 3 × 3 pixels at a time,
or 5 × 5 pixels at a time. To change the number of pixels being
sampled, press the Ctrl and E keys on your keyboard. The square
in the center of the close-up changes size to indicate the amount
of pixels being sampled.
Note:
The values shown for a group of pixels are an average of each pixel's
values.
In the Configuration dialog box, you can specify the default number
of pixels to be sampled when the Densitometer opens. See
"Densitometer menu" on page 2-23 for instructions.

Using the Preview Buttons

The Preview buttons let you zoom in on selected
portions of the previewed image.
Understanding EPSON TWAIN Pro Features
2-29