Using Chronos cameras

Here is some information about using the Chronos cameras in PIVlab. I have tested the Chronos 1.4, but not the 2.1. The Chronos 2.1 should work too.

Chronos limitations

Unfortunately, there are some limitations of the Chronos, and it is also pretty hard to get support from the manufacturers. The camera is very nice and extremely affordable, but this also introduces some hick-ups in the Chronos Firmware.

• Firmware 0.5.1 seems most stable and doesn't skip frames in the middle of a recording
• Disable "Debounce" in the "IO1 BNC" panel on the Chronos "Trigger I/O" Menu
• Click "Setup" in PIVlab Image acquisition panel and enter the IP address of the chronos like this: 192.168.254.100
• The resolutions entered here must be accepted by the camera. Not every resolution is accepted by the Chronos. e.g. 1280x720 and 1280x1024 is ok.
• Data transfer from Chronos RAM to SD card or SMB shared drive is slow.
• Tiff raw is the recommended file format although it is slow to save.
• H264 is much faster, but gives worse results.
• Stripes in image? Cover lens. Go to "Util" -> "Factory" -> "Black calibrate all resolutions" on the Chronos touchscreen
• Still stripes? Set camera to desired resolution, then goto main screen -> "Black cal" on the Chronos touchscreen (always cover the lens).
• Still stripes? Then go to "Record settings" on the Chronos, click the two "max" buttons and then "OK".
• Sometimes it also helps to change resolution to remove the stripes.
• A frame rate of 1000 fps is not possible on the Chronos when using an external trigger. In order to use 1000 fps, you need to slightly reduce the resolution to something like 1280x720. I have no clue why this is the case.
• In many cases, the Chronos will not properly shut down when you press the power button. A long press will force the camera to shut down. This seems to happen whenever the camera is configured to be triggered externally. You could circumvent this by initiating the live preview from PIVlab before you power the camera off.
• When powering the camera on, it is sometimes not clear if the camera is booting or if it hangs. Powering up the camera takes some time, so you may need to wait between 30s and a minute.

General tips

• I am using a VONETS VAP11s mini router connected to the Chronos. Then I can connect to the WiFi network of the Vonets and access the Chronos wirelessly.
• Use PIVlab to toggle between live image preview or PIV capture mode.
• In many cases, I am not enabling the "save" checkbox in the "Capture PIV images" panel in PIVlab. As soon as you click "Start" in the "Capture PIV images" panel, the chronos will capture images synced to the laser and will save them to the RAM ringbuffer, also when this checkbox is not enabled. You can stop the recording by pressing "Abort" in PIVlab.
• You might then use the Chronos Webinterface to save data to SD or SSD or SMB of the camera. This webinterface seems pretty handy to review, select and save the desired frames.
• You can of ourse also use the touchscreen of the camera to review, select and save the desired frames.
• Always make sure that you verify that image A and B are not confused. Sometimes, the Chronos skips the very first frame, resulting in an incorrect frame-straddling sequence!