CCD with USB 3.0 - xiD camera line¶
1: What were the conditions under which XIMEA measured/tested the xiD models ?¶
Temperature of environment: 24°C
Temperature of sensor: 35°C
Reading frequency (slow readout/fast readout etc.): 26/52/65MHz
Channels of readout: 1/2/4 TAP readout
Maximum dT between sensor and camera housing: 20°C (uncooled camera)
Total readout noise (photon transfer function):
conversion factor (gain): 0.68
e/ADU (analogue digital units): 0.74
e-/uV: 0.82 e-/ADU
Bias (offset): Compensated in AFE
Total readout noise: 7.2 / 8.8 / 9.7 e- (readout 26/52/65MHz)
Saturation/full well capacity: 20ke typical
Maximum linearity error: <1%
2: Will the measurement for dark current be added anytime soon?¶
Dark current is mostly compensated by AFE so it is almost impossible to measure it.
What we have measured is ~10^-12 ADU/s
It may be possible to calculate it from saturation level, however, this will contain leak as well.
Just for example: the dark current on MD028 is around 1.2 e/s/pix with 35°C inside the camera.
ROI feature (Region of interest) is increasing speed only proportionally to the height of full resolution - width does not have any influence.
It also has to be vertically centred.
For 4TAP, binning 1x1, 52MHz readout the frame rates are approximately:
1936 x 480 – 159 fps
1936 x 768 – 102fps
1936 x 1200 – 67fps
4: Is there a digital input that can be read with each frame and passed back in the form of frame header/metadata?¶
All IO's are sampled at the beginning of image transfer. Meaning 2 in and 2 out.
5: What is the pinout assignment for the connectors ?¶
Connector pinout depends on the camera: board level version has two connectors for IO and standard (housed) camera has only one.
It is best to consult the Manual
6: Are Sony CCD sensors (2.8, 6.1, 9 and 12 MP) available in taped glass versions?¶
Unfortunately, Sony sensors are not available with taped glass.
Customers can try to remove it on their own risk.
7: What will be the longest exposure time ?¶
Exposure value depends on readout mode.
For example, in the beginning it was 305s on MD028 model.
From API version 4.1.70 the camera models will be able to reach exposition of 713s in 1 TAP mode.
8: Is there a difference in the frame rate between 12 and 14 bit image acquisition or different packed modes?¶
All transfers are still 16bit so there is no difference for 8bit mode.
9: Where can I find a table with the frame rates for all implemented modes for all sensors (4-tap readout)?¶
It will be provided in camera specification.
Please check the Manual
10: Is binning mode 3x3 available (sensor and camera)?¶
Yes, this binning mode is supported and implemented.
Please check the Manual
11: Is there ROI restriction - will the speed increase proportionally to the number of lines or the whole area?¶
With CCD sensors, in general, the horizontal ROI (Region of interest) will not increase the speed.
Vertical ROI will improve speed, but it has also restrictions for the Region of interest, which has to be close to the middle of the frame.
12: What is the electronic gain range for the camera models?¶
Driver and API are the same.
However, testing may be advised as there are several controls different from xiQ.
14: Can the announced value of 57 fps at full resolution (2.8 Mpix) be increased even higher ?¶
The speed of 57 fps has been measured, however now it is possible to get 67fps in overlock mode of 65Mhz.
In the future, the plan is to go over 70fps in overclock mode 12bits.
Readout noise is similar for all modes.
The only difference is the number of TAPs.
15: How do you avoid light leakage on the sensor if a LED is used at the rear of the camera ?¶
For long exposure, it's indeed necessary to be sure to have no leaks of light and therefore the sensor is properly shielded from camera LED indication.
However, for longer exposures, it is wise to turn them off.
16: How do you handle humidity inside the camera and dew on the clear window in front of the sensor ?¶
Some cameras have a silica gel chamber to prevent humidity inside the camera and a way to reduce dew.
In this case, the Cooled cameras will have a different atmosphere – not air, but inert gas so there will not be any humidity and therefore no condensate.
17: Is there a special USB3 cable needed for operation of MD091 and MD120 models ?¶
These cameras require more power than cameras with a smaller resolution.
In order to deliver the expected current you should use cables with small resistance (e.g. short or good quality).
Please use our diagnostic application xiCOP to check if your cable has an acceptable resistance.
18: Will there be any effect of cooling on max framerate?¶
The simple answer is No - frame rate is effected through TAPs, MHz frequency and possible CMS.
CMS = Correlated multiple sampling.