Featured

All About Digital Photos

Read “What is a digital photo” and answer the following questions

1. The word ‘pixel’ is short for what?

Picture Elements

2. What three base colours are used to make all the colours in a digital image? What is this system called?

Colours: Red, Green, and Blue. This system is called the “24 bit RGB” System.

3. What is the total number of colours this system can produce?

This system can produce 16 million colours which is the approximation of what the human eye can apprehend.

5. Why do we sometimes have to scroll around in our screen to see the whole image?

Computers can only display so many pixels at once. There is a range of pixels a computer can display depending on the computer. Thus, an image is cut off or partly displayed, causing you to scroll down to see the entire image, when the “life size” image has larger pixel dimensions than the display.

6. What is the difference between dpi and ppi?

DPI (dots per inch) does not have anything to do with the digital photo, but it’s the resolution of a printer. Whereas, PPI (pixels per inch) is not the digital photo itself, but it’s the resolution of the printed output of a digital photo.

7. What are the four factors that work together to create photo quality? Of these four, which ones are under your control?

  • Quality of the recording device
  • Size, in pixels, of the digital image
  • Stored in digital format (lossless vs lossy compression)
  • “Eye” of the photographer and technical proficiency (under photographers control)

8. Why do large cameras generally take better photos than smartphones or compact cameras?

Larger cameras or dSLR’ have larger and higher quality sensors in which produce high resolution and/or good quality photos. On the other hand, smartphone or compact cameras do not have the pixel quality to compare to dSLR’, although, from afar and on a small display, the quality is not very contrasting.

Grading

Knowledge and Understanding /16

What is a digital photo?

1. What is the difference between a “lossy” and “lossless” format?

“Lossy” format means that all data is lost when the image is compressed. On the other hand, “lossless” format is when the original data from the image is not lost, even when its compressed.

2. What does JPEG stand for and when was it invented?

JPEG represents “Joint Photographic Experts Group.” and was invented in the 1980’s.

3. What kind of images is JPEG best for?

JPEG is best used for images, instead of images of text, because it relies on the blending of colour. It is a “lossy” format and it reduces the file size of an image by blending “redundant” image pixels.

4. What happens when you compress your images?

They become more blurry and pixelated, especially the focal points and smaller components of the photo.

5. Why should you save your images in a lossless format before you start editing

Them?

Although it may not be an obvious impact, saving an image in a “lossy” format such as a JPEG file will degrade the image if edited after and saved again. This occurs even if it appears to be set to the highest quality. Saving images in a “lossless” format and then editing the images ensures the best outcome and highest quality which results in a more favourable resolution. This is because no data is being removed from the original image.

6. What are the pros and cons of JPEG?

PROS of JPEG:

  • A small sized image/file  
  • Photographic reproduction that is good
  • The best format to be used when emailing or posting on the internet
  • They are compatible with nearly all image editors and viewing applications
  • Supports IPTC/XMP metadata with some softwares

CONS of JPEG:

  • The “Lossy” that removes data
  • Is able to compress and image by removing info that can never be recovered
  • Photo degradation occurs after editing a saved JPEG and again saving it

7. What are the advantages and disadvantages of JPEG2000 (JP2, JPF, JPX) and JPEG XR (JXR)?

JPEG2000 (JP2, JPF, JPX)

ADVANTAGES:

  • Small image size
  • Photographic reproduction is good
  • It has a lossless setting
  • Supports IPTC/XMP metadata with some softwares

DISADVANTAGES:

  • It is not supported by every software
  • It is not properly implemented by some softwares
  • It is not compatible with web browser

JPEG XR (JXR)

ADVANTAGES:

  • Small image size
  • Photographic reproduction is good
  • It has a lossless setting
  • Supports IPTC/XMP metadata

DISADVANTAGES:

  • It is not supported by all software
  • It is not properly implemented by some softwares
  • It is not fully compatible with web browser

8. What does TIFF stand for?

TIFF = Tag Image File Format.

9. Is it lossy or lossless?

It is lossless.

10. What are the pros and cons of TIFF?

PROS

  • “Lossless”
  • Supports IPTC/XMP metadata with some softwares

CONS

  • Very big file size even after being compressed
  • Has multiple “standards” making the file not readable for every program
  • It is not compatible with web browser

11. Can you insert a .tiff image into a google doc? (Try it).

No, I can’t insert a .tiff image onto a google doc.

12. Can you insert a .png image and a .psd image into a google doc? (try it)

Yes, you are able to.

13. Are .png and .psd lossy or lossless? (You’ll have to google this)

A .png and .psd are both lossless.

14. What is the advantage of .png over .tiff? (google it)

The advantage of .png over .tiff is that a .png is lossless. Even when the file/image is compressed it will keep all of the original data.

15. What three factors affect the filesize of a digital image?

(1) The filetype selected when storing the image, (2) The amount of colour that is  within the image, and (3) The specific colour mode that is chosen.

16. According to the chart, which 15 megapixel image takes up the least amount of

memory? Which takes up the most memory?

Least amount, ‘JPEG – 75%/Adobe 6 – 24 bit RGB’ and most amount of memory, ‘TIFF – LZW compressed – 96 bit RGB’.

17. How is this information (the information in the chart) helpful when you want to send an image by email?

The information in the char is helpful because it suggests what format the image should be in when being sent through email.

18. When we’re making the Yearbook, should we use CMYK images or RGB images?

CMYK due to the fact that it is better for printing.

Knowledge and Understanding /36

Wires, Cable and Wifi

1. Instead of letters and boxes, what does the Internet shift?

Binary information.

2. What is a bit?

It’s a pair of opposites. In the case of binary code, it is 1 and 0.

3. What do 8 bits make?

1 byte.

4. What do 1,000 bytes make?

1 kilobyte.

5. How many bits are there in the average song?

24, 000, 000 bytes.

6. What are the three ways we typically send binary information today?

Electricity, light and radio waves.

7. What are the pros and cons of each of these three ways?

Electricity

Pro: Cheap

Con: Signal loss

Light

Pros: Fast, no signal loss

Con: Expensive, hard to work with

Radio Waves

Pro: Mobile  

Con: Short Range

8. What is bandwidth and what is it measured by?

Bandwidth is the maximum transmission capacity of a device. It is measured by bit rate, which is the number of bits that are send over a period of time, typically in seconds.

9. What is latency?

The amount of time it takes for a bit to move from one place to another.

10. What is the major con of an ethernet wire?

There is measurable loss of signal when above a few hundred feet.

11. What is a fibre optic cable made of and what form of energy is it used to transmit?

A fibre optic cable is a thread made of glass. It is used to transfer and/or reflect light energy.

12. Where are fibre optics cables laid to connect one continent with another?

The bottom of ocean.

13. Wireless uses what to transmit bits from one place to another?

Radio signals.

14. Describe how an image transmitted from your device in Neuchatel reaches the device of your friend in Canada.

Steps:

  1. Image being sent from my phone would be coded using binary in my phone
  2. Sent image gets carried by radio waves from satellite
  3. Then converts to light waves in which are carried through fibre optic cables at the bottom of the ocean
  4. Light waves convert to radio waves from satellite that is located in close enough distance from friends device
  5. Image is transmitted back to binary
  6. Friend is now able to see image

15. Why is love necessary to the functioning of the Internet?

Love is necessary to the functioning of the internet because love is a key factor in which leads to internet use. This love can come in many forms, whether it be staying connected with loved ones when unable to be face to face or watching a show you are in love with. The internet is something that has the ability to create love, receive love and keep love consistant. Without love, the internet would have the same purpose and/or would not be used remotely as much as it does now.

16. Write down one question the video raised in your mind but didn’t answer.

What room is there for improvement in the transmission of binary?

Assessment of Learning .       /32