Archives for Mar,2010

As requested (by uplink) here are some images and calculations of the microscopes maximum zoom.

The images are taken with the edge of the camera case pressed right up against the ruler. You could probably remove casing to increase zoom slightly, or create a slot to slide a microscope slide into it. The camera has two focuses the first:

And the second (maximum zoom):

I am using my laptop screen as a typical screen and viewing the image at 100%. Poor mans calculations give you the following for the first focus and second focus:

1mm displayed over 40mm: zoom ~ 40x
1mm displayed over 150mm: zoom ~ 150x

(Note: Measuring magnification level is rubbish as it depends on screen the image is viewed on, so viewing it on a projector would make the statistics seem more impressive.)

The minimum zoom is less than this as we can move the camera further from the object:

Which is about 15x zoom. The microscope box states the zoom is between 10x and 200x, which from these tests seems a little over-exaggerated but not by much.

So I got a little carried away and started to take images of everything with my microscope:

Electronics

Materials

Eyes

Note the reflection in the image of my eye, if you zoom in and enhance you may be able to read what is on my screen which will then possibly lead to the solving of a murder.

I’ve wanted a USB microscope for a long time, and I have finally purchased a DigiMicro 200X Zooming USB Digital Microscope from dealextreme (product link) It only cost $40.23 USD (about £27.34 GBP) which I think is quite reasnoble for the fun and cool photos I’m getting out of it.

Quick Review
Advantages

• Very Cheap
• Easy to setup (plug and play)
• Can take some awesome photos, see below
• Three illumination settings (full on, half on, off) on top of software compensation

Disadvantages

• Controls (lights, zoom/focus and snapshot) are located on the body which make using them difficult if you are trying not to move your sample
• The stand is not very stable, tightening it to maximum holds it steady at certain angles for short periods of time
• Takes ~ 2 weeks to arrive from dealextreme as they are based in hong kong

Setup

The beauty of this webcam is that it requires no installation with ubuntu 9.10 you simply need to run the software and the camera works! woo! The output of `lsusb` shows the device as:

Bus 001 Device 006: ID 0c45:62e0 Microdia MSI Starcam Racer

and `dmesg` shows the following:

[22844.064666] uvcvideo: Found UVC 1.00 device USB 2.0 Camera (0c45:62e0)
[22844.080844] input: USB 2.0 Camera as /devices/pci0000:00/0000:00:0b.1/usb1/1-6/1-6:1.0/input/input9

Software
Most video programs will pick up the device, I am opting to use a program called cheese which is awesome not only because of the name but also because of its simplicity.

sudo apt-get install cheese

Lens Cap
Remember to take the lens cap off otherwise you will end up focusing on the plastic cap as shown below. It is fairly obvious if this is the problem as moving the microscope will only change the light levels not the image.

Pretty images

Any requests for microscope images (within reason) will be considered 🙂