Introduction and History Wide field fluorescence microscopy is used in research and health care because it offers extreme sensitivity in the detection of pathogens, cellular organelles and molecular complexes. A wide field fluorescent microscope can be either upright or inverted. These microscopes use intense light sources, excitation filters, barrier filters and are designed to detect substances that emit fluorescent light when excited.  Subjects are usually viewed against a black background. Fluorescent microscopy can even detect single fluorescent molecules under optimum conditions (H ..read more

Different samples require different microscopes. This rule refers to the fact that an opaque, bulky sample with a reflective surface needs another treatment than a transparent, unstained smear from the cavitas oris. The microscope stand offers the necessary space for a correct positioning of the sample and all options for the appropriate illumination method. The microscope objective is an even more specific item. Here we talk about the required resolution power (= numerical aperture), but also about cover glass correction, immersion method and working distance. Click here in case you didn't r ..read more

A closer look on Incident Light Microscopy reveals a new and noticeable fact. In a compound microscope for opaque samples, the objective plays two roles. First, like in a Transmitted light setup the objective is part of the imaging process. Quality and performance of the objective are essential elements to get reliable and “close-to-truth” results.  Secondly, the objective additionally is part of the illumination system. Light from the lamp house passes the illumination axis and is deflected by a 45° orientated semi-transparent mirror. Sent through the objective, the light is reflected by ..read more

For sure, a genuine rendition of color is a basic demand on any light microscope. Using white light as the inspection tool for microscopic samples causes a high challenge on the microscope optics. Different wavelengths set different focal points, and this Chromatic Aberration (greek: χρωμα chroma = color and latin: aberrare = deviation) has to be compensated by combining lenses of different shape and different glass types. In this sense, the Plan Apochromatic lens correction represents the highest level of color reproduction. Here the focal point for several wavelengths has been brought toget ..read more

By Dr. Robert Berdan August 22, 2022 Fig. 1. Caddisfly Oxyethira sp (Hydroptilidae) plus case by polarized light microscopy with a retardation filter. The scale bar shows the fly and tube is about 2 mm long (2000 microns). A scale bar adds size information and professionalism to the photograph. Light microscopes can magnify specimens about 1000X and resolve objects down to 0.2 microns (200 nm, nm = 0.000001 mm). Light microscopes capable of super resolution can detect objects to about 20 nm. Most light microscopes are used to measure organisms such as their length and width to aid in identifi ..read more

by Dr. Robert Berdan August 30, 2022 Fig. 1. Above is a hand cut section of an Aspen twig that was stained with Toluidine blue. Bright-field light microscopy 50X. Free-hand sectioning of living plant tissues with a single edge razor blade often provides an adequate method for rapid and inexpensive microscopic observation of plants internal structure. Moreover this simple technique often results in high quality images (A. Lux et al., 2005). Alternative methods to cut plant sections include the use of a hand microtome, vibratome, and a freezing microtome. Only free-hand sections and the hand m ..read more

By Dr. Robert Berdan August 15, 2022  Fig. 1. Above is a photo of a diatom arrangement from a prepared slide. The diatoms have been cleaned, arranged and then photographed using a microscope with dark-field illumination at 400X Diatoms are unicellular algae (Division Chrysophyta, Class Bacillariophyceae). Diatoms are microscopic in size, live in water, soil and moist environments, and exhibit highly ornamented glass houses made of silica with two parts that fit together like a Petri dish. Diatoms play an important role in producing about 20% of the earths’ oxygen and form an important p ..read more

Author: Motic Europe ADJUSTING THE ILLUMINATION In order to obtain maximum performance from your microscope’s optics - good, clear and crisp image - it is very important that the sample is illuminated correctly. For this reason, we would like to share with you some recommendations that will help you get the best image that your microscope can give.   LIGHT AND FILTER Turn on the microscope, focus your sample and adjust the light intensity (potentiometer) to an optimal level (1). Then place the daylight filter (blue filter) on the filter holder. This filter is usually included in the ..read more

Author: Motic Europe HOW TO AVOID REPAIRS We would like suggest some easy steps that will help you maintain the microscope in perfect conditions, and avoiding possible repairs. You might already know them, but we think it is good to refresh your memory from time to time.   BEFORE USING THE MICROSCOPE Read the instructions manual of the instrument carefully. Never attempt to disassemble the parts of the instrument, other than the ones described on the manual. Dust and dirt are two of the main causes for malfunction in a microscope. Avoid placing the instrument in locations exposed t ..read more

Author: Motic Europe THE C-MOUNT, A NEEDFUL THING For beginners, the combination of a light microscope with a digital camera includes some surprises. There are obvious discrepancies between the visual impression in the eyepieces and on the screen respectively. These discrepancies are about color impression and image section. The color impression in the eyepieces may be taken as a reference and depends on the color correction of the objective. The Plan Apochromatic lens design gives best preconditions for maximal color fidelity and resolution. The imperfection of a secondary spectrum, caused ..read more