Posts tagged ‘microscope’

Quick Review of Amazon Kindle 3G (plus some images and microscope images)

Sep 22 10

by mat

I recently ordered an Amazon Kindle 3G as I wanted an ebook reader to read papers and some of CommonsWare’s great android books and the kindle seemed like excellent value for money. It arrived today so here is a quick review along with some pictures:

Advantages

Cost – Only ~£150
3G – Free browsing web over 3G (worldwide!)
Wifi – For quicker browsing / downloading, works well no hitches.
MP3 Player – With speakers or headphone socket
Text to speech – So you don’t even have to read your ebooks any more, it even turns the page for you! The voice is quite good sounding only partially robotic; It manages pauses well with brackets, commas, etc. but sometimes doesn’t pause properly between paragraphs. Also some obscure words are mispronounced. I don’t know how good this would be for reading fiction as an audio book but this isn’t likely a feature I will be using much.
Viewing angle – due to the technology of the screen (E ink), you can still see the screen irrespective of angle (unless view is physically obscured obviously…)
– Screen is visible in direct sunlight unlike AMOLED phone screens
Supported formats – Supports MOBI (kindle), PDF, EPUB
Fits in my pocket – Just about fits in my pocket, with only a bit sticking out, this would obviously not be suited for long distance but as temporary holding place it is just fine.

Disadvantages

White is grey – Okay so the background is not completely white, more greyish, but I don’t really care it is still very book-like.
Scientific papers – Two column journal papers are a bit awkward to read or navigate using the current zoom settings

Neutral

You could fit about 26,000 into a olymic sized swimming pool

Photos

Amazon kindle 3G reading a nice android pdf with images

Amazon kindle 3G (Experimental settings; Web browsing, mp3 player, and text to speech)

Newspapers
There is a choice of which country you’d like to view newspapers from and in the UK there is a choice of 5 (Telegraph, daily mail, independent, financial times, and London evening standard notably the Times is missing… what are they playing at?) all of which offer a 2 week free trial of the newspaper or the purchasing of single issues or a monthly subscription (prices vary).

Newspaper subscription on kindle (free 14 day trial on most subscriptions)

Daily Mail viewed on the kindle, no crossword or puzzle page though

Microscope images
And as usual when I buy something new and exciting I have to look at it under a microscope

Amazon Kindle 3G display (No mag)

Amazon Kindle 3G display under microscope (Low mag)

Amazon Kindle 3G display under microscope (High mag)

Photos with my new usb microscope (20X-400X 1.3MP Digital Microscope)

Sep 3 10

by mat

I have been quite pleased with my previous microscope but I decided to buy a slightly better one from dealextreme as double the magnification was available for only a slightly higher cost.

product link) It only cost $48.20 USD (about £31.27 GBP) only $8 than my previous microscope that could only achieve 200x!

20X-400X 1.3MP Digital Microscope

20X-400X 1.3MP Digital Microscope with nice markings of the magnification

Quick Review
Advantages

Large dynamic zoom range (labelled 20x – 400x)
Easy to setup (plug and play)
Can take some awesome photos, see below
Variable illumination settings (using a wheel at top)
Rubberised casing gives better grip and good overall feel
Much improved build quality over the digimicro
Stand is sturdy and can hold camera still in place

Comparison to the digimicro

Digimicro vs New Microscope

Comparison of microscopes at minimum zoom level

Comparison of microscopes at maximum zoom level

Magnification measurement
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:

First focal point of microscope

And the second (maximum zoom):

Second focal point of microscope (0.5mm spacing between lines)

6mm displayed over 170mm: zoom ~ 30x
0.5mm displayed over 180mm: zoom ~ 360x

This isn’t far off the specified 20x – 400x so I am happy! (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

Setup in Linux

The beauty of this webcam is that it requires no installation with ubuntu 10.04 you simply need to run the software and the camera works! woo! The output of `lsusb` shows the device as:

Bus 001 Device 004: ID 0ac8:3610 Z-Star Microelectronics Corp.

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

Bonus Picture

This is a photo of the pixels on a nexus one phone to show the pentile pixel layout

Nexus One Screen Under the Microscope

As before any requests for microscope images (within reason) will be considered

TFT pixels in focus under high magnification microscope

Jun 11 10

by mat

Whilst working on this post I managed to get some sexy shots of pixels in focus from my TFT screen under the microscope.

Regular pixels from a TFT screen

Cool Focusing on pixels from a TFT High magnification

More Cool Focusing on pixels from a TFT High magnification

Nexus One’s AMOLED Screen under the microscope

Jun 10 10

by mat

After casually browsing this wikipedia article on google’s Nexus One (or HTC’s) I became interested in the AMOLED (Active-matrix OLED (Organic Light Emitting Device) screen due to its interesting pixel structure. Quote from wikipedia:

The Nexus One has a 3.7 inch AMOLED screen with PenTile matrix pixel arrangement. The raster resolution is 800×480 pixels, however each pixel in the PenTile RGBG display has only two subpixels (red and green, or blue and green alternately), rather than the three found in most displays. This gives it a total effective subpixel resolution of a 392×653 RBG display.[40]

So I decided to have a look under the microscope to see what I could find with my nexus one. Enjoy the following images:

Low Zoom

Nexus One's AMOLED screen under the microscope (Low magnification)

High zoom

Nexus One's AMOLED screen under the microscope (High magnification)

Regular Pixel

Regular pixels from a TFT screen

**Update: New images from better microscope**

Nexus One Screen Under the Microscope

DIY soil moisture sensors

Mar 28 10

by mat

I’ve been looking into creating an automated herbarium of some sort for a while, and I came across the brilliant post about creating some DIY soil moisture sensors using nails and plaster of paris. cheapvegetablegardener from hackaday.

Plaster of paris humidity sensor

Plaster of paris humidity sensor with wires attached

Both of the sensors

I wont explain all of the theory or background as it is already explained on cheapvegetablegardener.

Resistance experiment on moisture sensor

I measured the resistance of the sensor in air to be 12Kohms, I then placed the sensor into water (keeping the nail heads above the surface). The resistance dropped to 4Kohms whilst in the water, and then over 20 mins of back in air the resistance rose to 5.6Kohms. The sample still looks and feels quite wet, so I imagine it is going to take some time to dry, but from these prelimary results we can see it appears to work.

Soldering the wires to the nails before creating the plaster of paris along with covering the end sensor with hot glue would improve its longevity. I will post again once I find a better mould to make the plaster in as it was quite difficult to get them out of the cuvettes (I had about a 50% success rate).

Here is a microscope image of the surface of the plaster:

Microscope image of the surface of the plaster of paris

Measurement of microscope capabilities.

Mar 27 10

by mat

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:

Usb digital microscope's first zoom level of a ruler (markings at 0.5mm)

And the second (maximum zoom):

Usb digital microscope's full zoom level of a ruler (markings at 0.5mm)

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:

Usb digital microscope's minimum zoom level of a ruler (markings at 0.5mm)

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.

Microscope images of my eye (by request)

Mar 26 10

by mat

More microscope image of eyes were requested (by Benjie), trying to focus more on the detail of the eye by using external illumination. Unfortunately the camera has some colour problems when not using the built in LEDs, possibly because it attempts compensates for the lack of illumination. Hopefully I am not in danger of someone cloning my retinal scan to gain access to my confidential files.

Black and white microscope image of my eye

Clear reflection of my laptop in a black and white microscope image of my eye

Coloured illuminated microscope image of my eye

Coloured illuminated microscope image of my eye (see the blood vessels)

More microscope images (21)

Mar 20 10

by mat

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

Electronics

Magnified image of an intergrated circuit chip

Magnified image of an surface mount LED

Magnified image of an another integrated circuit chip

Magnified image of yet an another integrated circuit chip

Magnified image of a crocodile clip

Magnified image of a surface mounted resistors

Magnified image of a digital printed circuit board

Magnified image of a digital camera

Magnified image of a camera focussed on the glass

Magnified image of a camera

Magnified image of a headphone

Magnified image of a mobile phone speaker

Magnifieid image of a DVD

Materials

Magnified image of a dry sponge (with some solder burns)

Magnified image of a wet sponge (with some solder burns)

Magnified image of a caramel shortbread biscuit

Magnified image of a flapjack

Magnified image of demin

Magnified image of paper

Eyes

Magnified image of the queen's eye from a £10 note

Magnified image of an eye

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.

DigiMicro 200X Zooming USB Digital Microscope in ubuntu (linux)

Mar 20 10

by mat

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.

DigiMicro 200X Zooming USB Digital Microscope

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

Screenshot of cheese webcam software in action

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.