Wednesday, August 11, 2010


Detail of a fabric (inset: low resolution structure) 

Tuesday, August 10, 2010

Living animals in water river

 I just took a glass of water in the river nearby. I put some water on a plate and looked. Moving quite fast under the microscope... What these animals are, I have no idea. Help welcomed.

Dust at home...

You just put the microscope on a place that has not been cleaned for sometime (?). Enjoy...


Petunia observed with the Veho VMS-001, 20-200x Magnification USB Digital Microscope

Pixels directly observed on my computer screen

The screen is the one of a 
SDM-HS75 Sony TFT LCD color computer display 
Pixel pitch is given to be 0,264mmx0,264mm

Acari on cheese

These are Acari observed on some cheeses (see for example 
Crust of Mimolette and Tomme de Savoie is where you can find Acari City.

Feather structure and details

Same magnification as previously (except for inset that shows the shaft, or rachis, and the barbs). 
Again it would be nice to have Acari on this for direct comparison. 

Monday, August 9, 2010

Pixels on a printed image in a color magazine

Same magnification than the one used to see Acari (x200 approximately)
It would nice to put an Acari on this surface and to directly compare. Next time.

Dots per inch or pixels per inch. This is the number of printed points used to print a newspaper for example. No surprise: we cannot distinguish these dots or pixels with our eyes. This is done on purpose : images look smooth. x200 USB Microscope can easily overcome our eye limit and reveals the dot structure. On a picture taken on a magazine image, dots are easily identified. 
Common values for personal printers are 300 dpi and higher. 1200 dpi laser printer are available.
100 dpi corresponds more or les to a pixel of 250 micrometer or 0,25mm.

Welcome to SmallWorld-Mondepetit

What is the smallest thing one can see with her/his bare eyes ?  
Hard to say as it depends upon many aspects (light, quality of eyes, contrast,...)
However it seems that nobody can draw an Acari, living cells, red blood cells, plankton animals, details of an ant, etc, based on information given only by eyes.
We easily see a single black hair on a plate. The hair can be several centimetre long and around 100 micrometer thick. 
Printing of colour images in magazine nowadays is based on myriads of microscopic printed dots that our eyes cannot distinguish. In the quadrichromy system, the size of a single dot is comparable to the width of an Acari leg.  This is well below 100 micrometer. 
Observation of the world where we live at these scales can be done in principle rather easily. It requires an optical microscope with a magnification around x200-x400. At x400, an object with size 10 μm is shown to be 4mm on a screen (even larger if numerical zooming is applied). Schools and colleges are usually well equipped but one usually does not have his/her own microscope at home with these performances. 
What is new today, is the fact that there exists little and cheap (around 50$-100$ and close to the budget for many tools you are using everyday)  optical microscopes with these performances that can be used everywhere to explore what we want such as the surface of an old french cheese. This is one of my favourite as it i has been known for centuries that it is populated by so called Artisons or Cerrons, some kind of Acari that obviously like cheese crust very much and are very active. It might be fortunate that we do not see them when we eat cheese...
In this blog, I would like to show that:
  • There are a lot to be explored using these new microscopes around us at the microscale either looking at natural or at artificial, technological objects.
  • You do not have to learn a lot before using such a microscope: you plug it on the USB port of your PC and the microworld is yours.
  • Looking at films on Youtube and at images is fun. Looking on the screen of your microscope pointing your microscope yourself where you decided to do it is much more fun. It is your own exploration and observation. It might not be the best one, but it is yours in your own world. 
The microscope used here: 

This is the VEHO x200 see This is not the only one available but this is the one I used.

These examples are here only to propose directions which seems fruitful. All suggestions and new ideas welcomed. Furthermore if you manage to get better pictures than the ones I proposed in this blog, and if you want to have them here proposed, this is more than welcomed.
Proposed explorations : (other suggestions highly welcomed)
  • French cheese called Tomme de Savoie cerronée: enjoy a visit to Acari City.
  • Bird feather
  • Fly and insect details
  • Printed images in colour magazines
  • Water droplet
  • Your skin
  • Wall
  • Pollen, seed
  • Fruit and vegetable surfaces
  • Butterfly wing
  • Spider wires
  • Animals and plankton in water
  • Surfaces of stones
  • Dust: The microscope is looking upward inside home; the aperture has been covered by a transparent plastic film such as the one used in kitchen; focus on the plastic film and take a picture every time you think about it; of course the best would be a change in the software that enables one to take a picture every minute or every hour.
  • Scratches on your car (depressing)
  • ...