Perceptual adaptation

I am sure you have heard that the image of an object created on your eye’s retina is inverted (rotated by 180 degrees). The brain however has the ability to processes this information in such a way that makes you see things as they really are. This fact is remarkable and can give us a hint of how complex perception of reality is.

Fig.1. The image of real objects that is formed on our retina is inverted as compared to the original object. This happens due to the existence of the eye lens. However, we still do not perceive our environment as inverted.
Fig.1. The image of real objects that is formed on our retina is inverted as compared to the original object. This happens due to the existence of the eye lens. However, we still do not perceive our environment as inverted.

In the 1890s George M Stratton started out to test the theory of perceptual adaptation. Continue reading Perceptual adaptation

Solving criminal cases through crowd-sourcing

I started writing this post a few days ago after reading this article. It looked extremely interesting. The main idea is that in the Boston marathon there were thousands of mobile phones taking pictures and videos. The total duration and number of all videos and pictures shot could be stunning. This could be equivalent to thousands of witnesses testifying with absolute accuracy what they saw. The author was wondering whether crowd-sourcing could become a tool to crime solving. She probably meant to write modern crowd-sourcing as some forms of crowd-sourcing have been in use since long time ago as we will see further below. Continue reading Solving criminal cases through crowd-sourcing

Calculation of radiation dose to a material by using an ionization chamber

Dose deposition to a medium may only be directly measured by the method of calorimetry. However, this is not what we do in practice. What is usually done is that we use an ionization chamber of some kind to measure exposure and then apply a series of correction factors in order to derive dose values corresponding to the measured exposure. Continue reading Calculation of radiation dose to a material by using an ionization chamber

How to create web presentations using free software available online

This post is a tutorial on creating web presentations with free software. The software used is CamStudio (http://camstudio.org/) and optionally a web camera software called Yawcam (http://www.yawcam.com/). Yawcam is a camera software which can “stay on top” while you are presenting your slides. It is capable of showing your face or whatever is in front of your web camera during your presentation. So the end result will look somewhat like picture in picture functionality. The tutorial is given in video format below as well as in written instructions format. Feel free to follow whatever suits you best. Continue reading How to create web presentations using free software available online

Siding with reason