This is a focus-stacked photomicromosaic of a Dragonfly’s eye. What does that mouthful mean? Well at the magnification used (20x) the whole Dragonfly eye will not fit into the FOV of the Canon 5D MkIII on a research trinocular microscope. So in exactly the same way I need to create mosaics to get a BIG field of view (FOV) in astrophotography – I need to do the same with this large object in photomicroscopy. But there’s even more to creating this image. Because the object is so large, you cannot get the whole thing in sharp focus at just one focus setting. So you need to take what is called a focus-stacked image. To do this, you focus on the very bottom of the object and take a shot. You then move up a little and take another shot. You keep repeating this process until you get to the very top of the object. You then use a brilliant piece of software called Helicon Focus to combine all these individually focused images to create an image that appears to be in focus all the way down from the top to the very bottom. This makes it looks very much like an SEM (scanning electron microscope) image – but this approach has a HUGE advantage over an SEM image. Namely the Helicon Focus-produced image IS IN COLOUR.
Now as this image is a mosaic, you can see you have to focus-stack each of the individual images that go into forming the mosaic. It goes without saying that a focus-stacked photomicromosaic involves a LOT OF WORK in its preparation.