Posts that relate to the Keyword: Techniques

Phase Contrast vs. Bright Field Microscopy
Air is completely transparent, I hope you agree. And water is transparent. If this is indeed the case, then why is it possible to see air bubbles in water? The answer is, that the bubbles have a different refractive index than the surrounding medium, the water. Phase contrast microscopy is now capable of converting a [...]
Fixing specimens for making permanent slides
Before specimens can be processed for making permanent slides, they may need to be fixed. This step kills the specimen and preserves the structures. It also prepares the specimen for staining. There is no one single method to fix a specimen, too much depends on the nature of the specimen itself and on the subsequent [...]

How to make macro images
This time I’d like to talk about a topic which is only indirectly related to microscopy: macro imaging. Taking high-quality macro images can be quite a challenge and can involve quite a bit of trial and error until one has found the ideal conditions. The pictures of the rose have been taken with a Sigma [...]
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.



