PNDetector have released their Advanced STEM and Switchable Gain Advanced BSD modules with excellent performance enhancements over their traditional counterparts. They can be purchased as a complete system (including retractable arm, pre-amplifier and software) to seriously upgrade your electron microscopy capabilities.
Switchable Gain Advanced BSD

In “Fast” mode, you can traverse your sample at TV speeds, whilst maintaining excellent resolution and signal-noise ratio.

In “High Gain” mode, obtain detailed scans of the area of interest with accelerating voltages down to 500eV with perfect clarity.
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Advanced STEM