RAW files are often called ‘digital’ negatives because, like film negatives, they contain more of the original image’s information. With a negative, you’ve got more scope to improve the colors, contrast and exposure of the photo. Negatives contain a lot more image information than a print. In fact, they contain all the data captured by the film (or do they – more on this shortly).
So there is a strong parallel with the RAW files capture by digital cameras. They too contain all the data captured – this time by the sensor not by a piece of film. And you can process a RAW file to access more color and tonal information than you get from an in-camera JPEG.
It’s a simple and useful comparison that explains how RAW files relate to JPEGs. It’s also wrong.
RAW files are UNDEVELOPED negatives
Here’s the thing. A negative is not a pure representation of what was captured on the film. To get a negative, you first have to develop the film in chemicals. And the negatives you get will depend heavily on the development process and the chemicals you use.
If you shoot on color negative film you’re probably used to generic C41 processes, or an E6 process for slide film. You probably don’t give much thought to the chemicals used as these are standardized processes operated by labs.
But if you shoot black and white and do your own developing, you’ll know that even today there are many competing developers. Back in the heyday of black and white film photography, there were dozens, all promising ‘fine grain’, ‘high sharpness’, maximum shadow detail and exposure latitude, etc. Kodak D76 developer gave very different results to Agfa Rodinal, say, even with the same film. I know that because I used both!
The point is that the development process you use has a major effect on the negatives you get. So the negative from a film camera is not simply what was captured on the film, but also how it was rendered by the developer.
And it’s exactly the same with RAW files and digital cameras. Whenever you process and edit a RAW file, you are using a ‘developer’ to do it. This time, the ‘developer’ is your RAW processing software. And not all digital developers are the same.
Different RAW software gives different results
Let’s get back to this idea that a RAW file is a ‘digital negative’. It’s not. A RAW file is an unprocessed image, like the latent image on undeveloped film. The ‘digital negative’ you think you’ve got is simply how your software developed it.
The RAW development process includes a number of steps, but the key one is ‘demosaicing’. This is where the mosaic of red, green and blue pixels captured by the sensor is processed into a full-color image. Every program does this differently, and some do it much better than others.
Almost every photo editor these days can open and edit RAW files directly, but they are not equally good at it.
A good RAW processor will give you the best combination of detail rendition and noise control. An average one (which is most of them) just won’t be quite as good.
If you want the best possible quality from your RAW files (and your camera), it’s important to be aware of this. Shooting RAW files is not enough on its own to get you the best quality – you also have to process them with the right software.
The best RAW processing software
I’ve spent a long time shooting RAW files, processing them and trying out many different RAW processing programs. The results can depend not only on the software, but also on how well it handles specific camera brands. Of all the programs I’ve tried, these are the four I would pick out for the best RAW processing.
- Capture One: It’s a close-run thing between this and DxO PhotoLab, but Capture One doesn’t just deliver excellent results, it’s also a powerful and efficient editor.
- DxO PhotoLab: DxO’s RAW processing is as good as Capture One’s, and at high ISOs its DeepPRIME processing is exceptional – it’s better than anything else out there and can even make you rethink your camera’s capabilities. PhotoLab a powerful editor but somewhat technical too.
- DxO PureRAW: This is a batch processing tool that applies DxO’s excellent processing and lens corrections to your RAW files to produced part-processed ‘Linear DNGs’ – these actually ARE digital negatives. PureRAW is a great choice if you want to fit DxO’s processing into your existing workflow.
- Adobe Lightroom or Lightroom Classic: Both Lightroom versions use the same Adobe Camera Raw processing engine, and Adobe’s RAW processing is the simplest and most direct choice for countless photographers. It’s also not very good, and struggles to balance detail and noise, especially at high ISOs. It’s an average RAW processor, but very convenient.