so you read that the X5 does 16mp stills correct , can some one with more insight explain to me the DNG files , as most of mine are 23mb per pic.
I think you are confusing "megapixels" with "megabytes".
The term "megapixels" refers to how many pixels (dots) appear in a still image, with "mega" meaning "million". The X5 camera produces images that are 4608 pixels wide and 3456 high. That means that each image has 15,925,248 in it, or about 16 million pixels. Thus, a "16 megapixel image".
The term "megabytes" refers to how many bytes of storage are required for an image file. In the simplest form, each pixel requires 3 bytes of storage; 8 bits for red, 8 bits for green, and 8 bits for blue; 24 bits = 3 bytes. So 16 megapixels, times three bytes per pixel, means that each file would occupy 48 megabytes of space on disk.
But that isn't how images are stored on disk. The X5 camera supports two formats: JPG and DNG. JPG is a highly-compressed format, known as "lossy" because it discards sensor data in order to reduce the file size. The images
look like the original data, but they do not contain all of the sensor data.
DNG is a "raw" format, meaning that every bit of data from the sensor is encoded in the file. However, it is still a compressed format, and thus doesn't require the full 48 megabytes. It uses lossless compression techniques to reduce that to the 23 megabytes or so that you see.
It is my opinion that everybody should always use the DNG format, as 1) it gives the highest image quality that is possible, and 2) disk storage is insanely cheap. At 25 megabytes per image, a 2TB drive costing $75 can hold 80,000 DNG images. That's 100 photos a day for more than two years. And when that two years is up, a 4TB drive will cost $75.
