Using the Hybrid Detectors
On 3rd July 2014 three of the SP5's four photomultiplier tubes (PMTs) were replaced by new HyD hybrid detectors. The HyD detectors are in positions 1, 3 and 4. Position 2 is still occupied by a PMT because of a design limitation of the scan head. 
The HyD detectors are extremely sensitive, which means that it is very possible that illuminating specimens with the laser powers you are used to using with the PMTs will saturate them, causing them to shut down so they aren't damaged. If you regularly load saved settings from the instrument parameters or from saved data you should try the following steps before starting your scan to avoid inadvertently saturating the detectors:
- Set the laser powers to approximately 10 - 30% of what you would normally use
- Set the HyD gain to its lowest value of 10% (make sure it genuinely is 10% - occasionally the slider jumped back up to about 100% when I was doing this)
- This does not count for the detector in position 2, which is still a PMT and works in exactly the same way as before
If a HyD does shut down you won't see anything on the screen except if you have the Glow Over/Under look-up table applied. In the latter case the image will be totally green because every value will be zero. To reactivate the detector you can simply