D3 image size confusion
Consider the box with 36 cells. Each cell contain a coin. If all the coins are the same it's easy to remember .. 36 cells all containing the same type of coin. That process in your brain is called compression. Now switch to the box with different coins. You have to remember the type and position of each coin in case they are all different. There is nothing to compress and the amount of data you have to remember is much larger. In the third case you have the same box, first 18 are packed with one, and the second 18 with another type of coin... well, that's easy, but it requires more memory than the first case with equal coins. The size of the box remains the same for all three cases, but the amount of data to store in your brain is content aware. Whenever you are using the compressed jpgs and compressed raw format your camera tries to do the same (and a lot more). By zooming in the sensor size stays the same, but it's now packed with different pattern (types of coins ). The aperture affects DOF and consequently, the amount of detail (or blur, if you like) caught on sensor can also be different. Hope it helps.