Working with Multiple Cameras#
The quality of the distance measurement to a large extent depends on the amount of additional light that hits the sensor. This can be sunlight or light sent out by another camera. As a result, using two or more blaze cameras simultaneously would be problematic.
Methods for Operating Cameras Simultaneously#
There are different ways to enable you to use multiple cameras to capture the same scene.
Multi-Camera Channel Feature#
The advantage of the Multi-Camera Channel feature is that it can be used for cameras that are in the same room but not in the same network. These cameras are unable to communicate with each other in order to coordinate their acquisition timings so as not to interfere with the other cameras' light sources. A typical use case would be a warehouse in which several AGVs (automated guided vehicles) equipped with blaze cameras move around in a confined space. The maximum number of cameras is seven.
Synchronous Free Run Feature#
The Synchronous Free Run (blaze) feature is based on PTP and allows you to stagger the acquisition timings of the cameras so precisely to avoid interferences by the individual light sources completely. For this, the cameras have to be in the same network, e.g., connected to the same network switch. You can use synchronous free run in two different modes: consecutive and interleaved.
- In interleaved mode, the maximum number of cameras is two.
- In consecutive mode, the number of cameras that can be used simultaneously is theoretically unlimited. However, you won't be able to achieve the full frame rate anymore. For every camera you add, you will have to reduce the frame rate. The following table provides an overview of approximate frame rates.
Possible Frame Rates in Consecutive Synchronous Free Run#
This table lists approximate frame rates you may achieve in consecutive synchronous free run at an exposure time of 1,000 µs.
| Number of Cameras | Max. Frame Rate | Max. Frame Rate with Fast Mode Enabled |
|---|---|---|
| 3 | 10.2 | 22.6 |
| 4 | 7.6 | 17.0 |
| 5 | 6.1 | 13.7 |
| 6 | 5.1 | 11.4 |
| 7 | 4.4 | 9.8 |
| 8 | 3.8 | 8.6 |
Comparison of Multi-Camera Operation Methods#
The following table provides an overview of the different methods to help you decide which aspect is most important for you when operating cameras simultaneously.
| Multi-Camera Operation Method | Number of Cameras | Setup Effort | Common Network Required | Motion Blur | General Image Quality |
|---|---|---|---|---|---|
| Multi-Camera Channel | 7 | Low | No | Low | High, but decreases with number of cameras used |
| Sync Free Run – Consecutive | Unlimited, but frame rate has to be reduced for every camera added | High | Yes | Medium | High |
| Sync Free Run – Interleaved | 2 | Medium | Yes | Minimal | High |
Info
Teaming blaze Cameras With 2D Cameras
A special use case is the ability to synchronize image acquisition between blaze cameras and 2D GigE cameras, e.g., ace or ace 2 GigE cameras.
In this scenario, exposure on both cameras can take place at the same time as the 2D cameras don't emit light of their own and therefore can't interfere with the blaze camera.
As the infrared light of the blaze camera can interfere with the 2D camera, you should use a camera with an IR cut filter. If your camera doesn't have an IR cut filter, you can use synchronous free run to make sure that both camera types are not acquiring images at the same time. For this, you can use the interleaved or the consecutive synchronous free run, depending on the total number of cameras you want to use.
Follow these recommendations to avoid synchronization issues.