I'm writing this post cause it took me much time to find some free softwares that can record activities from screen for Windows and Mac systems. I use both OS at office and lab.
I'm doing some experiments. One is to measure the deformation of microcapsules, both loading curves and deforming capsules via a light microscope displaying on the screen; another is to observe the movement of nano/microcapsules in a cell. For both cases everything is displayed on the screen. I want to record them for kind of live show without using any external recorder and then converting clips.
I did a lot of search and find a better solution for both OS.
For Windows (NT/2000/XP) systems, CamStudio is great. It is FREE and OpenSource. Here is a short introduction from its website: CamStudio records activity from your screen and audio from a microphone into AVI video files and can also convert the AVIs into Streaming Flash videos (SWFs) using its built-in SWF Producer.
It can be downloaded here http://www.camstudio.org/ or http://sourceforge.net/projects/camstudio/
For Mac users (OS X 10.4), Copernicus is a super choice. It can record screen activities as quicktime movie. I tried and found great quality!
For more information, you can go ahead here: http://danicsoft.com/projects/copernicus/
BTW, I'm posting these not for advertising for them. Just for those people who are looking this kind of free software for their research.
Enjoy!