User guide

Chemi Doc
4-5
4.3 Step II. Acquire Image
For many white light applications, you can skip this step and save and print
images directly from Live/Focus mode.
For UV light, chemiluminescent applications, or faint samples, the Chemi Doc
control panel has several methods of creating image exposures. You can take
an automatic exposure based on the number of saturated pixels in the image,
you can enter a specific exposure time, or you can take a series of exposures
and select the best one.
Note: “Exposure” refers to the integration of the image on the camera CCD over
a period of time. The effect is analogous to exposing photographic film to
light over a period of time.
Auto Expose
Use Auto Expose if you want to take a single exposure but are uncertain of the
optimal exposure time.
Note: If you know the approximate exposure time you want (± 3 seconds), you
can skip this step and go directly to Manual Expose.
Click on the Auto Expose button to cancel Live/Focus mode and begin an
automatic exposure. The Auto Expose button will appear selected throughout
the exposure.
During the auto exposure, the image is continuously integrated on the camera
CCD until it reaches a certain percentage of saturated pixels. This percentage
is set in the Options dialog box. (Default = 0.75 percent. See Options below.)