Daheng Imaging cameras, lenses and frame grabbers

The machine vision task: from description to equipment

Start with the task: what must be seen, how the object moves and where the camera is installed. For example, checking the size of a part on a conveyor or verifying a marking on a line. The task defines which sensor, interface and lens are suitable.

Attach a sketch of the station with the distance to the object, the frame size, lighting and camera mounting position. These data are needed to choose the lens and to match the camera to the task.

Split the equipment list into camera, lens, frame grabber and software environment. This shows which items are included in the supply and which are already on the station.

The camera: type, interface and nameplate

Daheng Imaging series include area scan cameras with GigE, USB3, 2.5GigE and CoaXPress interfaces. The interface is chosen first, because the other positions of the kit depend on it. State it in the request in advance.

For MER2-G-P, MER2-U3-L, MER3-G3-P and MARS-X2, give the full designation from the nameplate. Models ME2S, ME2P, ME2L, ME3P, VEN and VE2S from the official list are confirmed against the manufacturer documentation.

Photograph the nameplate whole and in close-up, and if the housing has several labels, send all of them. This makes it faster to check the series and the configuration, especially for similar models.

The lens: focal length and sensor size

The HN-2M series includes eight lenses with fixed focal length. Together they cover 6 to 75 mm. The lens resolution is 2 MP, and the maximum sensor size is 2/3 inch.

Choose the focal length for the field of view your task needs. For the calculation, give the distance from the lens to the object and the size of the required frame. If a lens is already fitted, record its marking.

Keep dimensions in their original units, inches or millimetres. On the sketch, label what was measured: frame width, diameter or distance to the object. This avoids confusion during selection.

Interface, frame grabber and software environment

Daheng frame grabbers are offered for CoaXPress and GigE interfaces. Match the camera interface to the grabber interface and state both designations in the request. The combination is checked against the documentation.

List the software environment separately. PALLAS Vision is a software line developed by Daheng. HALCON and MERLIC are MVTec programs, and VisualApplets is a Silicon Software program. The catalog of the manufacturer lists them as third-party programs.

For the driver and camera setup, name the model, the operating system and the program you work in. This way the selection follows your exact set rather than a general description.

Several cameras and equipment replacement

For several cameras, prepare a table with the installation place, full designation, interface, quantity and photo number. Cameras with similar names can differ by suffix, so each line describes one position.

When replacing equipment, keep the full designation of the old position and state what changes: the camera, the lens or the frame grabber. If only the lens changes, describe the camera it is connected to.

Check the whole table before ordering. Each position needs a designation, interface, quantity and installation place. This makes it easier to agree on the composition of the supply.

What to write in the request for the task

Describe the object: the type of part or unit, the surface material, the size and the tolerance that matters for the inspection. These details help choose the camera and lens for the specific check.

State the object speed, the line operating mode and the required result: measurement, recognition or checking that an element is present. For a new project, add the city where the equipment will be installed.

If the task is described in words rather than a designation, send the full description. We select the equipment list from it and show which positions stay on the station.

Starting data for the field of view

To calculate the field of view, state the size of the object that must fit completely in the frame and the distance from the camera to the object. These two numbers define which focal length is suitable.

Add the camera sensor data: the sensor size and resolution. If the camera is already chosen, state its model. In this way the calculation rests on the documentation rather than on assumptions.

If the object moves, state its speed and direction. These data are needed to match the shooting mode with the task.

Frequent mistakes in a request

A common mistake is to state only the series, for example MER2, without the suffix. The official list has similar models that differ by suffix, so an unambiguous choice needs the full designation.

Another mistake is to omit the interface and the software environment. Without them it is unclear which frame grabber and software are needed, and the request comes back with questions.

The third mistake is to combine the camera and the lens in one line. Each position should be a separate line, which makes the supply easier to agree on and to check against the documents.

Parts for installed equipment

Parts and accessories for installed equipment are selected by the full designation and a photo of the nameplate. List the camera, lens, frame grabber and software on separate lines so that the kit is easier to check.