User manual

D: Focus Utilities
D.1 Overview
The preferred focus method for the Cohu 7100 cameras is to adjust the lens while watching the
Focus Window contained on the camera s internal Setup web page.
Several other methods of seeing the current focus level are also available:
 The LED Focus Utility
 The Telnet Focus Utility
 The Audible Focus Utility
 The Lens Selection Utility
All of the focus methods relay on the same basic idea - focus is best when the image is the
"sharpest." From the camera’s standpoint, sharpest means that the differences between pixels is
the greatest. The focus utilities below attempt to show where the maximum contrast between
nearby parts of the image occurs.
D.2 LED Focus Utility
For situations when you must focus the camera without having access to a browser or monitor,
use the camera Focus Utility. Initiate the camera s focus utility by inserting the end of a bent
paperclip into the Focus/Factory Reset slot on the back of the camera to depress the button.
Note: Before pressing the Focus/Factory Reset button, ensure that the camera is in its
normal operating cycle, indicated by the Green Status LED flashing at two-second
intervals.
Once you initiate the Focus Utility, the Red Image Capture LED on the front of the camera and
the and the Yellow Link and Activity LED on the back of the camera will begin to show focus
information. Both LEDs show the same information. While using the focus utility, if an LED is
on, your camera is going out of focus. When an LED is off, your camera should be coming into
focus. You can verify focus at any time by looking at an image from your camera.
Note: Do not block the camera s view while using the Focus Utility.
1. Gently rotate your lens (or focus-ring) all the way in either direction, until it stops. The
LED should be lit to show that the lens is out of focus.
2. Slowly rotate your lens (or focus-ring) in the opposite direction until the LED turns
off. This means your lens is near focus.
3. Continue to rotate the lens (or focus-ring) in the same direction as #2 until the LED
turns on again. This is the point at which your lens goes out of focus.
55 of 60