Using the blue, green, and red fluorescence channels we compared the transmission efficiency of a few of the 40X objectives in our collection.

For each objective, we took 4 or 5 unique measurements and averaged the mean intensities for the graphs below.  We were careful to use new unbleached regions of the FluorRef slides for the images.  Lighting conditions were identical for all images; the only change in the light path was the objective.   The intensity measurements are based on the throughput of the excitation wavelength AND the throughput of the emission wavelength AND include the camera sensitivity at different wavelengths.  This is less an absolute measurement than one of practical value for imaging with these particular instruments.  This is less exact than were we to have measured transmission of a narrower range of wavelengths.

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