About RAW files

Raw files are unprocessed images that reflect the image data coming from your camera sensor. Camera Raw Images cannot be directly printed or processed by regular, bitmap based processing or image editing software.
A special raw processor is necessary to interpret and process the image data.

With the use of proper software the files can be processed for further manipulation or printing into a tiff or jpeg file.Raw files are also often referred to as digital negative files.
While most common raw files are mainly based on the tiff format standard, they can be differences in the file syntax: Different image headers, image tags, file encryption and so on.
DNG is Adobe’s Digital Negative format which is not camera native and their standard is described as an extended tiff 6.0 format including several open image standards such es exif, xmp, iptc, icc profiles and more.

How To Process RAW files
As already stated, you will need a piece of software that provides you with the capability of reading the different camera raw formats and to process them.
There are Different companies providing such software such as Adobe, Phase one, Hasselblad and different software companies. Most of them are going to cost money.
You can try using free software to process your raw files but I recommend sticking to the known sowtware which has its place in the industry for a reason.
You might have to import your images first in order to process them correctly. After being processed the raw files need to be exported into a comon known format depending of further use.
As you intend to retouch your images, you will need to export them as psd files or as tiff files. Those formats are commonly used for retouching and can be open within your image editing software of choice. We recommend using Photoshop for your retouching work.

Why retouching RAW Vs. Jpeg
Raw files provide more image data as jpeg files. They are unprocessed, are used in a much larger color space and therefore give you more options to shift, change and control saturation of colors. They also give you the opportunity to use icc and dng based camera profiles to correct your image data when shot with different lenses and bodies to make them look the same (colourwise).
In general, raw files contain more data, more bit depth and can be compressed as to show more detail in shadows and highlights than a captured jpeg format can.
Shooting raw is associated with being a professional. Within the retouching industry it is basically the same. You want to start with good images, when it comes to the file format. This is as important as the image content, model, lighting, posing, composition,…