I have added this section concerning digital image post-production as this is so very important for maximizing the utility of every camera and lens. We often read reviews of lenses or cameras where a criticism is of a nature that it can easily be addressed in post. For example, vignetting in some lenses. Such is quite easily removed (or added if you wish!) in post. So I will build upon this incrementally over time but beginning with DxO PhotoLab 6 Elite, which I believe is an exceptional Raw file processor. Ed Ruth also teaches post-production in Bakersfield, California. Link to classes here. Link to my book page here.
Knowing when to “quit” is an important aspect of post-production.
Although post-production software can be used to process any digital image file, photographers who shoot Raw have a distinct advantage.
What is Raw shooting?
Using your camera’s menu you may choose any number of image outputs. These often include JPEG Large, JPEG Medium, JPEG Small, Raw & JPEG, and Raw (sometimes compressed Raw). I choose Raw for every shooting situation, except perhaps, interval shooting where a large number of images in Raw format would be timely to process.
The advantages of Raw shooting are many. First, Raw is an image file not a finished image. To process a Raw file, we must use software such as DxO PhotoLab to “demosaic” or interpret the Raw data. In the final stages of using such software, we choose the file format and make changes to image size as appropriate for our needs, photo print or online media. Typically, we choose a JPEG or TIFF file format. A TIFF file retains far more data than a JPEG file and is useful if further software rendering is anticipated such as in Photoshop.
Second, a Raw file includes exactly what your camera’s sensor captures. A modest amount of in-camera alteration is needed for us to use the Raw file. Much of what a camera’s “CPU” does to process the light that strikes a sensor involves math most of us would run from screaming.
Third, a Raw file has a wider “dynamic range” than a JPEG file. While all digital images range from black point, shadows, three-quarter tones, midtones, quarter tones, highlights, to white point, a Raw file delivered to us at 16-bit depth whereas a JPEG file is an 8-bit file. Eight-bit (2 x 2 x 2 x 2 x 2 x 2 x 2 x 2) gives us 256 tones from black point to white point whereas 16-bit gives us 65,536 tones from black point to white point. In digital post-processing, 16-bit is like having $65,536 for vacation vs $256. Both are in the same black point to white point wallet, but the greater sum offers you many, many more options.
If we alter shadows or white point in a JPEG image, we risk banding or loss of color detail. With a 16-bit Raw file we would really have to go nuts to risk losing a detectable amount of tonal information. Suppose we took an image 5-stops underexposed. Using Raw processing, we can bring such an image back to the point where we can recognize it. Not so much with a JPEG file.
Fourth, Raw gives us everything our sensor can deliver without compression, All JPEG images are compressed to some extent, thus JPEG Fine, Normal, or Basic compression ratios. Consequently, a JPEG Small with Basic compression is a small image indeed. A Raw file can be output to any JPEG size or compression ratio. Raw’s power is in post-production options. These are many.
Fifth, white balance adjustments are a “side-car file” to a Raw file. Not so with JPEG where white balance is backed into the finished JPRG product. This is not to say we cannot add a touch of cool blue (higher Kelvin color temperature) or a dash of amber (lower Kelvin color temperature) to a JPEG file but with a Raw file no tonal information is lost in the transition.
Sixth, although shooting Raw requires Raw processing software, DxO PhotoLab performs this task effortlessly for almost every imaginable camera. In fact, DxO has researched almost every combination of camera and lens to produce a workflow that maximizes the potential of the camera and lens you are using. So, when I shoot My Nikon Z50 with my Sigma 50mm f/1.4 Art lens, no worries. DxO has tested this combination and PhotoLab responds accordingly.
Seventh. When you shoot Raw, we do not have to worry about Picture Control, high ISO noise reduction, “Scene” modes as PhotoLab can deal with all such stuff. Lens distortion or chromatic aberrations are also managed very well by PhotoLab.
Eighth, to enlarge an image for print, nothing beats what can be done with a Raw image. There are a number of programs available that can double the effective resolution of your modern digital camera without noticeable (mentionable anyway) loss of detail.
I hope that I have talked you into switching from JPEG to Raw. But if you have been a JPEG shooter for some time, you can transition from JPEG to Raw gradually by shooting both (Raw + JPEG in the menu).