When using a camera microscope it is significant for the microscopist to take good photograph, store, and use digital microphotographs using modern digital cameras and transmitted-light microscopes. Discussion focuses on selection of cameras adapt well to microscope eyepieces or trinocular heads, and on camera settings and procedures to obtain best quality photographs. Image resolution and size settings and valuable recommendations are also discussed here. Prior to specifying a camera of choice and recommending camera settings let’s review the purposes of digital microphotography of particular interest to aerobiologists and other microscopists, First, to develop a large reference library of known particles - so images will be mostly stored on a computer, in some data base form. Images need to sharp, often with multiple exposures at different focuses, to exchange email images with other professionals to obtain assistance in identification, but images by email should be reduced in file size for convenience and transmission speed, to print with professional reports - usually these are limited in physical size.

This is a distant third in importance in my practice. There are some factors involved in obtaining and using good photomicrographs it is importstnt that you start with a well prepared slide, choosing a mountant with good optics for the particles being examined. Fungal spores or pollen grains may benefit from hydration but not excessive hydration. Heavy use of colored stains risks obscures natural colors and features needed for identification, though the use of fuchsin, lacto phenol, or even India ink for occasional development of certain features may be applicable. Following a well prepared and clean slide, be sure the microscope is properly set up for illumination, and be sure the objective is clean. You also need to select a camera which has a very good lens. Lens resolution in macro mode and with the camera focused at infinity are both important. Post processing of images may improve the image color balance, sharpness, or contrast, but no amount of processing can produce accurate image data if that information was not captured in the first place. Even excellent photomicrographs are not useful if they cannot be located later for reference purposes.

A good photographic data base system is important. The image formation chain determines image quality in digital photos through the microscope. Microscope resolution, including the quality, cleanliness, and adjustment of every lens in the light path. Before starting the process be sure the microscope is clean and that illumination Light source (color temperature, focus, etc.) has been established. Light source (color temperature, focus, etc.) Adjustment of the condenser, Adjustment of the field diaphragm, condenser aperture, and where provided, objective aperture and eyepiece aperture), Placement of the well-prepared and clean slide on the microscope stage, Choice of objective lens and use of oil-immersion (higher magnifications reduce the demands on the camera’s photo array of pixels), Eyepiece and camera mount adjustment (and where provided, calibration of the camera lens focal distance to match the eyepiece distance - or infinity), Camera resolution, Post capture image processing and Observation of Resolution. What these mentioned link means is that the quality of the end result of photomicrography is limited by the weakest link in the image-formation chain.

For example, no amount of camera pixels will provide a sharp image of an object which is not resolved sharply in the microscope nor will a high-pixel camera produce a sharp image if the camera’s lens is of limited ability. Beware: not all high pixel cameras have equally sharp lenses, so the “resolution” in megapixels can be misleading. High megapixels defines how many data points of image are being recorded. But if the lens and other steps in the image formation chain are not producing a sharp image, high megapixels means you’re recording a lot of unclear data.