Sensors exposure times¶
CMOS sensors¶
Most of CMOS sensors generate the exposure interval internally.
For a few, it is possible to control it by external signalling.
The sensor internal timing depends on the provided system clock.
Most of the sensors are using dividers to generate slower clocks for internal state machines.
The exposure time is mostly defined by a number of row times, where the row time is dependent on various internal settings.
Almost none of them supports exposure time equal to zero.
There is defined minimal exposure time as well as steps between possible exposure times.
SENSOR | Minimum exposure | Exposure step | Maximum exposure | Note |
e2V EV76C560 |
15.625 µs | 15.625 µs | 1 sec | |
CMOSIS CMV300 |
54 µs | 7.56 µs | 1 sec | defined for maximum bandwidth (1) |
CMOSIS CMV2000 |
16.2 µs | 2.69 µs | 1 sec | defined for maximum bandwidth and 8bit per pix. For more bits, the values will double (1) |
CMOSIS CMV4000 |
26 µs | 2.69 µs | 1 sec | defined for maximum bandwidth and 8bit per pix. For more bits, the values will double (1) |
CMOSIS CMV12000 |
19 µs | 6 µs | 1 sec | With ROI feature (2) |
CMOSIS CMV20000 |
94 µs | 16 µs | 1 sec | |
CMOSIS CMV50000 |
100 µs | µs | 17 sec | |
On Semi VITA1300 |
74 µs | 1 µs | 1 sec | step 1 µs if exp < 65.54 ms; 4 µs if exp < 262.1 ms; 16 µs otherwise |
On Semi PYTHON1300 |
29 µs | 1 µs | 1 sec | step 1 µs if exp < 65.54ms; 4 µs if exp < 262.1 ms; 16 µs otherwise |
LUXIMA LUX13 |
1 µs | 1 µs | 1 sec | |
LUXIMA LUX19 |
1 µs | 1 µs | 1 sec | |
Sony IMX174 |
19 µs | 4.96 µs | 3 sec | |
Sony IMX252 |
19 µs | 5.29 µs | 3 sec | |
Sony IMX250 |
20 µs | 6.32 µs | 3 sec | |
Sony IMX255 |
25 µs | 10.54 µs | 3 sec | |
Sony IMX253 |
25 µs | 10.54 µs | 3 sec | |
Aptina MT9V034 (Currera) |
10.83 µs | 0.042 µs | 10 sec | |
Aptina MT9P031 (Currera) |
36.38 µs | 36.38 µs | 10 sec | full resolution (2) |
Aptina MT9P031 (MU9P) |
110 µs 1 ms |
110 µs 110 µs |
10 sec 10 sec |
full resolution in Rolling Shutter mode (2) full resolution in Global Reset Release mode (2) |
(1) - By decreasing bandwidth, the minimum exposure time and exposure step will increase
(2) - Decreasing the width of the image and the use of downsampling further decreases the value of the minimum exposure time.
CCD sensors¶
Maximum Exposure Times¶
Following table shows maximum exposure times in minutes for different camera models and different modes:
readout frequency | 26 / 52 MHz | 65 MHz | ||
model \ readout mode | 2/4 TAP | 1 TAP | 2/4 TAP | 1 TAP |
Sony ICX674 | 6.54 min | 11.88 min | 5.24 min | 9.51 min |
Sony ICX694 | 8.71 min | 16.24 min | 6.98 min | 13 min |
Sony ICX814 | 10.4 min | 19.62 min | 8.34 min | 15.69 min |
Sony ICX834 | 12.69 min | 24.18 min | 10.16 min | 19.35 min |
Minimum Exposure Times¶
Triggered Modes
All triggered modes have minimum possible exposure time 26 microseconds.
Not Triggered Modes
If the camera frame is not triggered by hardware or software, the minimum exposure time is different for different models and modes.
Following table shows minimum exposure times in microseconds for different camera models and different modes:
readout frequency | 26 / 52 MHz | 65 MHz | ||
model \ readout mode | 2/4 TAP | 1 TAP | 2/4 TAP | 1 TAP |
Sony ICX674 | 47 µs | 66 | 43 | 58 |
Sony ICX694 | 54 µs | 82 | 49 | 71 |
Sony ICX814 | 61 µs | 94 | 54 | 80 |
Sony ICX834 | 69 µs | 110 | 60 | 94 |