“My Nikon D90 has numerous features for modifying the colour saturation, contrast, sharpness, D-Lighting, Noise Reduction, etc. of images that I will shoot. But is it important to use any of these overrides when shooting in the Raw mode?”—Ray Burns
Most D SLRs do provide many picture style modes such as Landscape, Portrait and Vivid as well as the overrides you mentioned, Ray. And these are certainly valuable when using JPEG capture mode or Raw + JPEG. Make the appropriate settings for any type of subject and you’ll need to do less work in your imaging software; this will also maintain optimal image quality.
When a D SLR captures raw data, the settings you chose are recorded in the Metadata (EXIF) file but they are not “locked-in” as they are with JPEGs. Open a Raw photo in the converter software developed by the camera manufacturer, and the preview will be accurate. It will reflect the picture style and the overrides that you had set. If the preview looks fine, simply go ahead and convert it to JPEG or (preferably) to TIFF. If you have chosen suitable in-camera settings, you won’t need to spend a lot of time modifying many aspects of a Raw photo.
Some shooters prefer to use aftermarket software to modify and convert their Raw photos. That’s fine and it also allows for modifying any aspect using the available tools. However, the software will not be able to determine all of the in-camera settings you made, such as picture style, levels for Saturation, Sharpness, Noise Reduction, dynamic range expansion and so on. Hence, the preview displayed may look entirely different than the Raw photo that you had viewed in your camera’s LCD screen display.
Note: If you are using the latest version of Adobe Camera Raw in Photoshop or Lightroom, the Camera Calibration utility allows you to select a picture style to be applied to a Raw capture. While this is an extra step, it does minimize the amount of time you will need to spend with other tools to achieve a pleasing effect for any type of subject. The results are excellent, closely matching the effects you’ll see in JPEGs made with the same in-camera picture style.
So the bottom line is this. I do recommend using in-camera picture styles and overrides in Raw capture mode if you plan to use the camera-maker’s converter program. If using another brand of converter software, only the settings for more common aspects—such as exposure and white balance—will be important. The more sophisticated camera features you had used will be ignored. This is one reason why I prefer programs such as Nikon Capture NX 2, Canon DPP, Sony Image Data Converter or Pentax Digital Camera Utility when testing various D-SLR cameras.