Posts that relate to the Keyword: Techniques

Taking stable photographs with a microscope

Specimens which are suspended in water are not completely immobilized. Small objects will start to vibrate when one is tapping on the table on which the microscope stands. The optics of the microscope will magnify even the smallest vibrations. These vibrations become problematic when taking pictures with a photo camera which is mounted directly to [...]

Virtual microscope: The Tick

This is a darkfield image of a tick. Ticks are blood-sucking arthropods. They possess 8 legs and are not insects, but rather are related to the spiders. Ticks are known to transmit various diseases, such as Lyme’s disease and encephalitis.
For more information on the tick, read the following post: .

Increasing Contrast using Optical Methods

Many microscopic specimens are either very thin or transparent or lack color. They lack contrast and can not be easily seen in bright microscope light. In many cases it is not possible or desirable to chemically stain the specimens. In this case, optical techniques become necessary to enhance contrast.

Hydra, a fresh-water polyp

Hydra, a fresh-water polyp.

Dry-mounted permanent slides

Wings of insects, small insects and other small specimens do not have to be enclosed in a mounting-medium, they can also be dry-mounted. If they are completely dry, then they will also store for a long time.

Fructose Mounting Medium for Permanent Slides

Many mounting media for making permanent microscope slides include organic solvents and are less suitable for the use in classrooms, at home and with children. In this article I would like to show you how to make fructose syrup to be used as a safe mounting medium.

Enhancing Photomicrographs

There are a range of different possibilities:

Enhancing contrast: Photo editing software (such as Adobe Photoshop or GIMP) contain functions that enhance the contrast of an image. Find the menu point “Auto Levels” or simply “Levels”. This tool will make the darkest part of the image black (even if it was not black before) [...]

Oblique Illumination

Oblique illumination is a contrast enhancing technique which can be realized with the use of home-made filters (patch stops) placed into the filter holder of the microscope condenser.

Darkfield Microscopy

Darkfield microscopy is one of the simplest and cheapest contrast enhancing techniques. It works well for specimens that have a refractive index which is different from its surrounding medium, but which are difficult to see because they lack color. Dark field microscopy shows the specimen bright on a dark background.

Working with the condenser aperture diaphragm

The condenser aperture diaphragm (or iris diaphragm) is used to control the contrast and resolution of an image. This article explains the usage of the diaphragm.