Table 3:
WFCAM performance.
| Item |
Specification |
Units and notes |
| Average detector QE |
0.54, 0.62, 0.61 |
In J,H,K, and averaged over 4 devices |
| Focal plane Coplanarity |
50 |
 m peak-to-valley over 4 devices |
| IR Pixel clock rate |
187 |
kHz |
| Focal plane readout time |
0.7 |
Seconds. Includes extra reset for stability |
| Read noise |
<30 |
Electrons in correlated double sample mode |
| Median delivered image quality |
0.7 |
Arcseconds. K-band FWHM. Near zenith |
| Best delivered image quality |
0.55 |
Arcseconds. K-band FWHM. Near zenith |
| Astrometric errors |
<0.1 |
Arcseconds over full field of view, after |
| |
|
correction for field distortion |
| Field distortion |
 |
Centre-to-corner change in plate scale |
| Systematic photometric errors |
<0.02 |
Magnitudes. Over the field of view |
| Total system throughput in Z,Y,J,H,K |
0.14, 0.16, 0.20, 0.28, 0.29 |
including telescope, filter and detector QE |
| |
|
Relative to a perfect telescope and instrument |
| |
|
of 10.5 sq. m collecting area |
| Autoguider magnitude limit |
17 |
I band at 40 Hz. No moon |
| WFCAM average observing efficiency |
0.55 |
(time spent integrating)/(elapsed time) |