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A Prime Color camera can be equipped with either the 12mm F#1.8 lens or the 6mm F#1.6 lens. The 12mm lens is zoomed in more and is more suitable for capturing at long ranges. On the other hand, the 6mm lens has a larger field of view and is more suitable for capturing wide area.
Both lenses have adjustable f-stop and focus settings, which can be optimized for different capture environments and applications.
Note for 6mm F#1.6 lens: When capturing 1080p images with 6mm F#1.6 lens, you may see vignetting in each corner of the captured frames due to imager size limitations.
Detecting Dropped 2D Frames
Every 2D frame drops are logged under the Status Log panel, and it can also be identified in the Devices pane. It will be indicated with a warning sign next to the corresponding camera. You may see a few frame drops when booting up the system or when switching between Live and Edit modes; however, this should only occur just momentarily. If the system continues to drop 2D frames, that indicates there is a problem with receiving the camera data. If this is happening with Prime Color cameras, try lowering down the bit-rate, and if the system stops dropping frames, that means there wasn’t enough bandwidth availability. To use the cameras in a higher bit-rate setting, you will need to properly balance out the load within the available network bandwidth.
Note: Due to the current architecture of our bug reporting in Motive, a single color camera will not display dropped frame messages. If you need these messages you will need to either connect another camera or an eSync into the system.
Since each color camera can uplink quite a large amount of data over the network, the size of the recorded Take (TAK) can get pretty large. For an example, it a 10-second take was recorded with total data throughput of 1-GBps, the resulting TAK file will be 10-GB, and it can quickly fill up the storage device. Also, especially with multiple color camera systems, it is recommended to use a fast storage drive (e.g. M.2 SSD) that can quickly write recorded capture data from the RAM memory. If the write-out speed to secondary drive isn't fast enough, the occupied memory in RAM storage may gradually increase to its maximum.
The eStrobe synchronizes with Prime Color cameras through RCA cable connection. It receives exposure signals from the cameras and synchronizes its illuminations correspondingly. Depending on the frame rate of the camera system, the eStrobe will vary its illumination frequency, and it will also vary the percent duty cycle depending on the exposure length. Multiple eStrobes can be daisy-chained in series by relaying the sync signal from the output port to the input port of another as shown in the diagram.
When capturing without eStrobes, the camera entirely relies on the ambient lighting to capture the image, and the brightness of the captured frames may vary depending on which type of light source is used. In general, when capturing without an eStrobe, we recommend setting the camera at a lower framerate (30~120 FPS) and increasing the camera exposure to allow for longer exposure time so that the imager can take in more light.
Info: Frequencies of typical light bulbs
Now that you have set up a camera system with Prime Color, all of the connected cameras should be listed under the Devices pane. At this point, you would want to launch Motive and check the following items to make sure your system is operating properly.
When you launch Motive, connected Prime Color cameras will be shown in Motive, and you will be able to configure the settings as you would do for other tracking cameras. Open up the Devices pane, and select a Prime Color camera(s), and at the bottom of the pane, key properties that are specific to the selected color cameras will be listed. Optimizing these settings are important in order to capture best quality images without overflowing the network bandwidth. The key settings for the color cameras are image resolution, gamma correction, as well as image compression and data transfer rate settings, which will be covered in the following sections.
Default: 1920, 1080
This property sets the resolution of the images that are captured by selected cameras. Since the amount of data increases with higher resolution, depending on which resolution is selected, the maximum allowable frame rate will vary. Below is the maximum allowed frame rates for each respective resolution setting.
Default: Constant Bit Rate.
This property determines how much the captured images will be compressed. The Constant Bit-Rate mode is used by default and recommended because it is easier to control the data transfer rate and efficiently utilize the available network bandwidth.
Available only on Constant Bit-rate Mode
Bit-rate setting determines the transmission rate outputted from the selected color camera. The value given under this setting is measured in percentage (100%) of the maximum data transmission speed, and each color camera can output up to ~100 MBps. In other words, the configured value will indirectly represent the transmission rate in Megabytes per second (MBps). At bit-rate setting of 100, the camera will capture the best quality image, however, it could overload the network if there is not enough bandwidth to handle the transmitted data.
Since the bit-rate controls the amount of data outputted from each color camera, this is one of the most important settings when properly configuring the system. If your system is experiencing 2D frame drops, it means one of the system requirements is not met; either network bandwidth, CPU processing, or RAM/disk memory. In such cases, you could decrease the bit-rate setting and reduce the amount of data output from the color cameras.
The image quality will increase at a higher bit-rate setting because it records a larger amount of data, but this will result in large file sizes and possible frame drops due to data bandwidth bottleneck. Often, the desired result is different depending on the capture application and what it is used for. Thus, the below graph illustrates how data size how they are related.
Tip: Monitoring data output from each camera
Data output from the entire camera system can be monitored through the Status Panel. Output from individual cameras can be monitored from the 2D Camera Preview pane when the Camera Info is enabled under the visual aids () option.
Default : 24
Gamma correction is a non-linear amplification of the output image. The gamma setting will adjust the brightness of dark pixels, midtone pixels, and bright pixels differently, affecting both brightness and contrast of the image. Depending on the capture environment, especially with a dark background, you may need to adjust the gamma setting to get best quality images.
Once you have set up the system and configured the cameras correctly, Motive is now ready to capture Takes. Recorded TAK files will contain color video along with the tracking data, and you can play them back in Motive. Also, the color reference video can be exported out from the TAK.
Once the camera is set up, you can start recording from Motive. Captured frames will be stored within the TAK file and you can access them again in Edit mode. Please note that capture files with Prime Color video images will be much larger in file size.
Once the color videos have been saved onto TAK files, the captured reference videos can be exported into AVI files using either H.264 or MJPEG compression format. The H.264 format will allow faster export of the recorded videos and is recommended. Video for the current TAK can be exported by clicking File tab -> Export Video option in Motive, or you can also export directly from the Data pane by right-clicking on the Take(s) and clicking Export Video from the context menu. The following export dialogue window will open and you will be able to configure the export settings before outputting the files:
The size of the exported video file can be re-encoded and compressed down further by additional subsampling referred as chroma subsampling, which is not supported in Motive. However, such subsampling can be achieved using a third party video processing software, and doing so can hugely reduce the size of the exported file. This is supported by most of the high-end video editing software, but Handbraker (https://handbrake.fr/) is a freely available open-source software that is capable of doing this. Since the exported video file can be large in size, we suggest using one of the third-party software to re-encode the exported video file.
› Q : Can custom camera lenses be used?
A: The Prime Color camera uses the standard C mount lens, and you can use lenses from other vendors to use the color camera; however, there will be no guarantee for the lens and image quality. For this reason, we suggest using the Lens that we provide.
› Q : What's the difference in Prime Color FS?
A: The Prime Color FS is equipped with a filter switcher that allows the cameras to detect in IR spectrum. This allows the color camera to be calibrated into the capture volume using an IR LED wand, and once this is calibrated, 3D assets (markers, rigid bodies, skeletons, cameras) can be overlayed on top of the recorded reference camera view.
› Q : Slow memory write out
A: If the disk drive on the host PC is not fast enough to write the data, the RAM usage will gradually creep up to its maximum memory when recording a capture. In which case, the recorded TAK file may be corrupted or incomplete. If you are seeing this issue, you will have to lower down the bit-rate to reduce the amount of data or use a faster disk drive.
› Q : There are frame drops even when there is enough bandwidth availability
A: Dropped 2D frames with Prime Color in the system can be introduced due to the following issue: