Video fluorescence microscopy

The LED illuminator and filter block were mounted on a Nikon Optiphot stand. These microscopes are study, basic microscopes equipped for basic transmitted light illumination technique, and are used throughout our teaching laboratory.

A C-mount video camera is mounted above the filter block at the primary image plane of the objective. Sensitivity and S/N are major concerns with fluorescence microscopy, and I have experimented with a variety of low cost surveillance cameras that contain sensitive Sony ExView HAD CCDs.
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The JAI-3300 camera (£500) provides a colour signal along with in-camera frame integration and buffering, and the 2046XAI monochrome camera from RF Concepts (£100) provides a 0.003 lux sensitivity. The monochrome camera is indeed very sensitive, but doesn't allow discrimination of different colour fluorescence (including autofluorescence). It is best suited to clearly labelled specimens, or perhaps for use with narrow bandpass filter, rather than the cheap longpass filter that is used currently.

Video signal were passed to a video-firewire converter (Data Video DAC-100, £180 see below), and captured using a laptop computer with a firewire port. I've used an Apple powerbook, but PCs will work as well, and the the video signal can also be captured using a framegrabber or simply viewed directly on a monitor.
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