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Version 1.3 rev 13 May 2015
The circuits used in the camera head are extremely sensitive to static electricity and radiated electromagnetic elds and
should not be used (or stored close to) EMI/RFI generators, electrostatic eld generators, electromagnetic or radioactive
devices, or other similar sources of high energy elds. Types of equipment that can cause problems include Arc welders,
Plasma sources, Pulsed-discharge optical sources, Radio frequency generators and X-ray instruments.
1.7 pRevention of condensation
Condensation may form on the outside of the camera body if the temperature of the cooling water is too low or if the
water ow is too high. The rst signs of condensation will usually be visible around the connectors where the water
tubes are attached. In such circumstances switch off the system, disconnect the power supply and carefully wipe the
camera with a soft, dry cloth. It is likely there will already be condensation on the cooling block and cooling ns inside
the camera. Please also carry out the following actions:
• Set the camera aside to dry for several hours before you attempt re-use
• Before re-use blow dry gas through the cooling slits on the side of the camera to remove any residual moisture
• Use warmer water or reduce the ow of water when you start using the device again
• Check Dew Point (refer to Appendix B)
1.8 em gain ageing
It has been observed that some EMCCD sensors, more notably in cameras that incorporate L3Vision sensors from e2v,
are susceptible to EM Gain fall-off over a period of time. This ageing effect applies to any EMCCD camera manufacturer
that incorporates L3Vision sensors into their cameras. The Andor iXon Ultra 897 model uses an L3Vision sensor.
A technical note entitled: ‘EMCCD - RealGain
TM
& EMCAL
TM
’ , which further explains this phenomenon, can be
downloaded from the Andor website: http://www.andor.com/library/publications/?app=543
1.8.1 minimizing em gain ageing in youR iXon ultRa cameRa
If left unchecked, EM Gain Ageing has the potential to signicantly compromise the long-term quantitative reliability of
EMCCD cameras. Andor has implemented innovative measures to stabilize the EM Gain on these sensors and ensure
the long term quantitative stability to the user. If these guidelines are followed EM Gain Ageing can be minimized and
should not present any real problem to the user.
More details of this ageing effect and Andor’s solutions can be found on Section 4.1.7. Some of the guidelines to
minimize the EM Gain ageing process are listed below:
• Do not use EM Gain values greater than necessary to overcome the read noise. A gain of x4 or x5 the rms
read noise (accessible from the spec sheet or performance sheet) is more than sufcient to render this noise
source negligible. In practice, this can be achieved with EM Gain of less than x300 at 10 MHz and x450 for
17MHz operation. Pushing gain beyond this value would give little or no extra Signal to Noise benet and would
only reduce dynamic range.
• Only select the extended EM Gain scale of x1000 for single photon counting applications and always
ensure that the signal falling onto the sensor is within the regime of low numbers of photons per pixel.
• Turn down the gain when the camera is not acquiring.
• Try not to over-saturate the EMCCD sensor.