Raw or jpeg? Or raw conversion responsibility

We have heard this question many times: raw or jpeg? And the obvious answer is both – raw and jpeg!Raw is, in fact, a precursor to jpeg. Every single jpeg image has passed a raw stage.
   A much more interesting question is: Who takes responsibility for the raw to RGB (jpeg of tiff) conversion, and how is it performed?

Who's in charge?
When you choose jpeg in the camera, you let the camera software (camera manufacturer software programmers) take responsibility for the raw to jpeg conversion. Sometimes this is not a bad choice. It's convenient! More space on the memory card. Sometimes (coincidentally) the pictures look OK.
   However, there are moments when you wish you had taken a bit more responsibility yourself. That is when you end up with under or over exposed pictures. Or when white balance is out of range for ordinary jpeg editing rescue operation. Or when colors need some final touch. That is when convenience has a price.
   Don't forget:  when you choose jpeg, you are responsible for correct exposure and white balance setting when shooting.

The raw choice
On the other hand choosing raw means heavier image files and more job. But does it really mean that much more job? It is in fact quite easy to set up a more or less automatic raw to jpeg workflow where you end up with nice jpegs without sacrificing the comprehensive raw format of your pictures. It's like in the "old days" when you used negative rather than reversal film. There was an intermediate stage between shooting and finished print. In digital photography raw is the negative and RGB is the finished print. When you have the negative/raw you have so many possibilities to interpret the picture. With reversal film/jpeg from camera you are, more or less, stuck with one interpretation. Or at least with a picture with limited possibilities to influence.

Invisible and visible posterization
Posterization is the effect of "stepping" a tonal scale, the opposite to continuous tone images. All digital images are, by definition, posterized since the tonal scale is not continuous. In an 8 bits per channel digital image you have a maximum of 256 levels of red, green and blue (= 16 777 216 possible different colors). The posterization is by any normal standard not visible. The moment you change anything in an RGB image, you loose gradation with increased posterization as a result. Numerous or extensive adjustments of the RGB image results in decreased gradation and, at some stage, visible posterization. All picture editing at the RGB stage is technically speaking destructive and non-reversible.

Raw advantages
There are many advantages with raw compared to jpeg from your camera. The only exception is when the in-camera raw to jpeg conversion coincidentally manage to hit the perfect RGB interpretation regarding, color temperature (white balance), exposure, contrast, gamma and colors. As we mentioned before, the moment you need to adjust one or several of these parameters (which is possible to a limited extent in RGB) you loose gradation with increased posterization as a result. 
   If you are a serious photographer who cares about image quality (apparently you are, since you are reading this article) there are always matters to improve regarding image quality. These improvements can basically be divided into four groups.
Tonal scale: Black point (exposure), white point (contrast) and gray point (gamma).
Color temperature: White or gray balance. Balance between red, green and blue.
Color quality: Hue and saturation.
Sharpening: Digitally photographed pictures are improved by some sharpening, even if you use the best camera, lenses and a tripod.
Perform your adjustments in raw and you will end up with an improved RGB picture (jpeg or tiff) with full 3 x 8 bit gradation. Furthermore the range of improvement possibilities is much greater in raw than in RGB.




Low effort high quality solutions
Many advanced digital cameras have a raw and jpeg option. Save both, use jpeg until you find it not sufficient. Open the unsatisfactory pictures in raw and make necessary adjustments.
   Or, much better, set up an automatic raw to RGB conversion batch processing workflow. Set white balance, sharpening, custom profile, lens correction, etc. Take a break while your pictures are being processed. Go through them all with a critical eye and mark the ones that need further attention. Open them one by one in raw format and make necessary adjustments manually.

Profiling for colors in raw
The single most difficult image adjustment matter is color adjustment (hue). Colors are always influenced by camera and light. In order to see the colors of your image files properly, you need a calibrated high quality monitor and proper surrounding environment with conformed ambient light. And you need a good memory in order to finally adjust image colors to resemble the colors in the photographed scene. In practice this is an impossible task. Luckily there is a much better, much less complicated, much faster and much more accurate solution: Custom camera and light profiling!

Jpeg profiling
Profiling jpegs is possible but not recommended. While profiling in raw is performed in a linear color stage, almost all jpegs have S-shaped RGB curves. Since the S-shape varies, perfect profiling is impossible. Furthermore, since the image information in jpeg is truncated, there is less room for improvement. This is a minor disadvantage for good jpegs, but for jpegs that need more extensive color adjustment the truncated information might be insufficient. However, even if profiling raw is by far the most advantageous color assurence option, a profiled jpeg is better than no profiling.

QPcard camera profiling
QPcard camera profiling has many advantages when compared to other solutions. When color nuances for the reference cards 202 and 203 were chosen, we had modern digital camera sensor filters in mind. The selected 35 colors reveals best possible information about camera color behavior in order for our application to optimize matrices and LUTs in the profiles. In less than 5 seconds the profile application has identified the card, compensated for un-even exposure, sampled 6400 measurements from each color, kept the 3200 most favorable, and calculated a complex high quality profile. Furthermore the application offers possibilities to fine-tune the profile for personal preferences. There is a free choice to generate profiles for large, medium or small gamut final images. For "control freaks" who prefers to manually map linear colors into a certain color space, large gamut is the choice. For newspaper photographs intended for print on low budget paper, the small option is preferred. 
   QPcard camera profiling is un-beatable for photographs taken in difficult light circumstances like sport arenas or industry buildings. We have had several testimonies about unbelievable results with a minimum effort during such circumstances. Do you prefer Adobe Photoshop or Lightroom? Then you choose .dcp profiles. Are you accustomed to icc based applications like Capture One, Phocus or DXO? No problem; just choose .icc profiles instead. 

Next step in camera profiling evolution
You are a professional news photographer. You have no time to spare for picture editing. The news agent needs the photos now! You have an assignment in a location with difficult light and the camera jpegs do not look good, with peculiar colors affected by the light.
   First solution: connect your camera to your laptop running Adobe Camera Raw. Save your raw images in a hot folder managed by ACR. Set up a workflow with a camera profile customized for the light on your location. Send processed jpegs to a folder connected via wifi to the news agent. Result: A happy job initiator.
   Second (future) solution: Import the custom profile to your camera. Send jpegs direct to the news agent from your camera. Canon already have a profile editor called Picture Style Editor. As soon as we know the structure of Canons profiles, we can start working on a solution where our application automatically generates correct profiles for in-camera use. If you have returning assignments at different arenas you can store profiles for these arenas in your camera. Just remember to activate correct profile before shooting.