Frequently Asked Questions

When exposure time and frame rate are set, and you decrease the AOI (Area of Interest), our EO USB2.0 cameras try to maintain the same bandwidth that was originally preset. This results in frame rate increasing, or if it is already at its maximum, exposure time decreasing. However, you can easily reset any of these settings. Also, you can use the included software to fix two of the three settings if you do not want them to change.

The power requirements that you outlined tip the scales in favor of FireWire. USB can only deliver 2W of power but Firewire Cameras, specifically FireWire.b cameras, can deliver a maximum of 25W. Though FireWire.b cables are actually rated to withstand 45W, using the lower value is recommended for safety reasons.

There are probably two issues at play that are cause the problem. First, make sure there is enough bandwidth for the amount of data to transfer. If this is insufficient, then the cameras won’t be able to acquire and transfer their data over the network. Second, it is known that GigE Cameras do not work the same with all network cards; it is best to use the recommended one though the manual does not require it.

The power requirements that you outlined tip the scales in favor of FireWire. USB can only deliver 2W of power but Firewire Cameras, specifically FireWire.b cameras, can deliver a maximum of 25W. Though FireWire.b cables are actually rated to withstand 45W, using the lower value is recommended for safety reasons.

If a pattern (such as a crosshair) is needed to be placed over the image in a digital system, the combination of an image capture board and image analysis software can be used. If the same effect is needed for an analog system, a video micrometer is typically used. It is a device capable of laying controlled lines or patterns on an analog video output signal that is transmitted to a video printer or monitor. The only other way to place crosshairs, guidelines, or complex patterns on the image is to use a glass reticle placed in the video lens or microscope. Since most video lenses do not have this ability, using an electronic device is a viable alternative solution. For microscopes, an eyepiece that can accept a reticle is used and a relay lens is then used to connect the scope to the camera. Since different video micrometers have different functions, care must be taken to select the model that has the necessary capabilities.

Yes, you do need a frame grabber that is compatible with both your computer and digital camera. Even though the camera outputs digital data, the available computer ports (RS-232 for example) do not have the bandwidth or even the right connectors to be able to be used with a digital camera.

Depth of field describes the difference between the closest and furthest distances at which an object will maintain a certain level of resolution without refocusing, whereas depth of focus describes the different sensor positions through which focus can be maintained with a stationary object.

Test targets can be used to evaluate or calibrate an imaging system's performance. The correct assessment of an imaging system is used in certifying proper measurements, establishing a baseline between systems working in parallel, or for troubleshooting. Edmund Industrial Optics offers patterns that can characterize image quality in terms of its components: resolution, contrast, depth of field, and distortion. Each target has its own unique design that defines its application. Several targets can also be applied to test for other image quality characteristics. For a definition of the image quality terms and recommended targets, view Choosing the Correct Test Target.

An in-line video system introduces illumination into the imaging lens before the objective and aligns it with the optical axis. The "in-line" name actually refers to the type of illumination and is also known by other names such as axial, co-axial, through-the-objective, vertical, and incident brightfield. The clear difference from other types of illumination is that in this case the light is transmitted through the objective. As an example, we offer an InfiniTube In-Line Assembly that uses infinity-corrected objectives. The image from this type of objective is collimated (parallel) light prior to being focused by a secondary lens assembly onto the sensor plane. Since the light between the objective and secondary lens is collimated, the separation between the lenses can be adjusted to accept a beamsplitter that will introduce horizontally aligned input light and redirect it vertically down to the objective. This type of illumination is very efficient for high power objectives that need to evenly illuminate an opaque object, such as a semiconductor wafer. Since this type of system is very sensitive to mounting with objective powers 20X and higher, we recommend using a vibration isolation table (not available from Edmund Optics). For proper focusing, a rack and pinion movement is always suggested for the system.