Topicm5ac7312e971da63a_1528449000663_0Topic

The methods of digital photography acquiring

Levelm5ac7312e971da63a_1528449084556_0Level

Second

Core curriculumm5ac7312e971da63a_1528449076687_0Core curriculum

Grades IV‑VI

III. Using a computer, digital devices and computer networks.  Student:

1) describes the functions of basic computer components and external devices and:

a) uses devices to record images, sounds and videos, including mobile devices,
b) uses a computer or other digital devices to collect, organize, sort and select his/ her own resources;

Timingm5ac7312e971da63a_1528449068082_0Timing

45 minutes

General objectivem5ac7312e971da63a_1528449523725_0General objective

Learning the methods of acquiring images.

Specific objectivesm5ac7312e971da63a_1528449552113_0Specific objectives

1. Understanding the methods of image acquisitionimage acquisitionimage acquisition using a camera.

2. Understanding the method of acquiring the image from the scanner.

Learning outcomesm5ac7312e971da63a_1528450430307_0Learning outcomes

The student:

- identifies the methods of acquiring images with different devices,

- knows the rules of creating colour images on digital displays.

Methodsm5ac7312e971da63a_1528449534267_0Methods

1. Flipped classroom.

2. Problem lecture.

Forms of workm5ac7312e971da63a_1528449514617_0Forms of work

1. Individual work.

2. Group work.

Lesson stages

Introductionm5ac7312e971da63a_1528450127855_0Introduction

Answer the introductory questions.

1. What does it mean to acquire a photograph?
2. What are the methods for acquiring a digital image?
3. How do the colours appear on the digital display?m5ac7312e971da63a_1527752256679_0Answer the introductory questions.

1. What does it mean to acquire a photograph?
2. What are the methods for acquiring a digital image?
3. How do the colours appear on the digital display?

Procedurem5ac7312e971da63a_1528446435040_0Procedure

Task 1

Read the text and then make a short note in a graphic form e.g. using the elements used in the information block diagrams or thoughts map.

People have ever since tried to capture reality that surrounds them. First, they painted on rocks then they produced bas‑reliefs and paintings. Since the end of the 19th century, they have been taking photographs with analogue photographic cameras. At the end of the twentieth century digital photography developed and in short time it practically displaced analogue photography. The principle of producing a digital image is very similar to analogue photography. The difference is the fact that the photosensitive elementphotosensitive elementphotosensitive element such as photographic film has been replaced with a matrixmatrixmatrix of electronic photosensitive elements i.e. a system that contains a large number of light sensors that convert the image into electronic signals. Every element is responsible for registering one image point (i.e. pixel), and the main electronic circuit of the digital camera reads this information while the picture is being taken and saves it to the memory cardmemory cardmemory card in a generally accepted format.

Pictures which are taken using this method look like a small mosaic, with a number of points depending on the number of matrix sensors. The effect can be seen immediately on the camera displaydisplaydisplay, in the form of a digital photograph.

[Interactive graphics]

In the digital camera there is the Bayer's filterfilterfilter (Bayer's grid). It looks like a three‑colour chessboard with red, green and blue fields. Thanks to this, the pixels of the matrix „see” the light in three basic colours: red (R), green (G) and blue (B). Such pixel sensitivity to a particular colour is called the filter matrixmatrixmatrix.

Task

Open the geogebra applet “Creating colours”. Answer the question: what conditions must be met in order to  different colours on the ?

[Geogebra applet]

[Illustration 1]

Miniaturization of elements and constant development of their potentials enabled the construction of very small digital cameras; they are a standard element mounted in mobile phones (smartphones), as well as in tablets or laptops.
Thus, thanks to the development of digital technology, photography has become available to everyone. Taking a picture with the camera which is mounted in a mobile phone is easy and we can see it just after shooting. Currently, the technology of digital image recording (both photography and movie) is common and available to you as well.
It is worth to mention one very important property that digital data has, namely that the date does not change over time. A digitally saved photo or video will be exactly of the same quality after many, many years. In comparison, analogue images lose quality over time. Black and white photos and videos fade, and colour ones lose and change colours. This is an unavoidable process associated with the changes in chemical compounds that disintegrate over time. To protect analogue images which are taken in the past from being completely destroyed, we convert them into digital ones. We can do this with scanners. Scanners can be built in almost the same way as digital cameras, but more accurate images require more advanced constructions. In a typical scanner, the matrix has the shape of a strip with photosensitive elements arranged in a row which can register a single line with high accuracy. The strip is moved slowly in front of the scanned object and registers line by line, which in the end gives us a complete picture To use the scanner you should connect it to the USB connector and install the appropriate software most often sold together with the device.
Then just put a photo or another document in the device, specify the image resolution and decide whether it should be a colour or a black‑and‑white image. After selecting the file format, start scanning. It should be remembered that increasing the image resolution is associated with increasing the size of the file that is recorded on the disk.

Task 3

Scan any photo using the scanner. Set the appropriate resolution, consider whether the image should be colour or black and white. Compare the size of the files after scanning the document with a different resolution.

Lesson summarym5ac7312e971da63a_1528450119332_0Lesson summary

Acquiring digital images is possible using a digital camera or a scanner. Both devices operate on the basis of light sensors equipped with a matrix of colours.m5ac7312e971da63a_1527752263647_0Acquiring digital images is possible using a digital camera or a scanner. Both devices operate on the basis of light sensors equipped with a matrix of colours.

Selected words and expressions used in the lesson plan

image acquisitionimage acquisitionimage acquisition

displaydisplaydisplay

lenslenslens

matrixmatrixmatrix

reflex camerareflex camerareflex camera

filterfilterfilter

memory cardmemory cardmemory card

photosensitive elementphotosensitive elementphotosensitive element

sensorsensorsensor

shuttershuttershutter