## The Strange Adventures Of A Pixel

** (Just because someone wanted to know!)
**

**What is a pixel?**

**It is a single spot which can represent any colour within the bounds of physics for the device.**

**How can we understand pixels?**

**Firstly let us think of some units of measurement:**

**kilo K 1 000**

**mega M 1 000 000**

**However in Computers:**

**1024 is a kilobyte (kB), 1024 x 1024 is a megabyte (MB)**

**(mibibytes MiB in binary 2 ^{20 } same size as a MB, not an SI measurement)**

**In Cameras to find the Dots per inch we use this formula: **

** Resolution = Print Size**

** Dots Per Inch**

**With colour about 250 dots per inch is about the minimum amount of dots that are needed for the human eye to see before an image begins to look a bit broken up and made of squares.**

**(It might be useful to think of being close to a Monet picture.)**

**A Nikon chart for some cameras has some Megapixel cameras with these pixel sizes:**

Megapixel |
Resolution of Camera |

10.75 |
3872 x 2592 |

12.9 |
4228 x 2848 |

16.9 |
4928 x 3264 |

**So what can you reasonably expect with a portrait shot on the 10.75 Megapixel camera.**

**Can we do a 16 x 24 inch? To find out we must calculate the DPI.**

**(DPI) We calculate the Values of X and Y as below. **

**3872 / X= 16 (Answer X= 242)**

**2048 /Y = 24 (Answer Y= 85) **

**So 242+85 = 327 DPI This would call a good quality picture to look at, as for it’s content that is a whole other story. **

**(Note this is printing portrait from a landscape shot, we would get a better score had we taken the shot as a portrait !)**

**However the same camera printing to 32 x 48 inches would give 168.5 DPI you will see squares!**

**Want your own copy of this a PDF:
**