theSuede
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cgardner wrote:
The biggest difference with respect to color correction is that RAW records color in blue/yellow and green/magenta channels, not RGB. That makes it easy to adjust white balance with a tweek of the blue/yellow slider, or eliminate the greenish cast seen shooting under trees with a tweek of the green/magenta slider.
Another advantage is bit depth. JPEGs are 8-bit (256 values) per color. In RAW you can use 16-bit (4048 values) per color which produces smoother gradients in areas like skies. WIth 8-bit JPEG corrections in curves or levels can cause posterization banding which won't with the same correction in the 16-bit file. A caveat when editing the RAW in 16-bit is you'll also want to use Adobe RGB or ProPhoto RGB as the editing color space in ACR, then convert to sRGB before converting to JPG at the end of workflow for screen images, a minor extra step vs. an all sRGB JPG workflow.
The "belt and suspenders" approach is to shoot in RAW+JPG. Try it for a few hundred shots, long enough to get the hang of RAW and edit a variety of images. Do what you normally to with the JPG for basic color / exposure / contrast correction. The do the same adjustments on the RAW copy in 16-bit mode, save as JPG, then compare with the camera generated JPG. You should find the more you need to correct capture flaws in exposure / color balance the better the result are with the RAW.
Well, not quite true (regarding color)...
The colors as recorded by the sensor, filtered by the CFA on top of the sensor, are physically in fact quite close to the normal digital positive "Red, Green, Blue" that we all use in standard color spaces like sRGB and Adobe RGB. Canon however use a scheme that is more like "orange, warm green, blue", but they're the only ones in larger cameras that do. It's a scheme that most compacts and smart-phones also use, to sacrifice color accuracy in daylight but gain luminance noise-performance and have less color twists with peaky lights like fluorescents.
But every camera uses a color profile to translate from the non-standard and quite model/make-specific color response you get 'off the sensor' of every digital camera into a general standard color space that everyone "knows how to interpret". Otherwise you couldn't share images with your friends, customers, or indeed on the net - you have to have some 'common grounds' format to use, so that everyone knows what they're seeing. sRGB and Adobe RGB are the two most common standards.
If you shoot jpg-in-camera, the camera processor does this transformation before saving the image.
If you use a raw-converter, the profile is applied in when you open the image, in stead of when the camera saves the image.
This leaves some very interesting options - you can then apply a profile suited to your needs, your preferences, or the light at the scene you shot and so on.
The color the camera actually records does NOT react (and change!) in the same way that your eyes do when you change the lighting on the scene. The error between daylight (camera vs eye) and fluorescent energy saving bulbs (camera vs eye) can be up to 20dE depending on camera / situation. And this has absolutely nothing to do with white-balance - even perfectly white-balanced, colors will change as the light changes.
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So, colors are one part of the change - you have more options to get it right without sacrificing tone-resolution. The other part is contrast and local contrast.
One of the tricks with a smooth and effortless raw PP process is to find a good base setting - something you can use for all imported images , as a base starting point when the images leave the memory card and enter your computer.
Lightroom has several good options to play around with and set, change, make new or delete those presets, or indeed several slightly different versions of the same preset. But my current configuration has taken me some years to arrive at - though I can't say that I was dissatisfied at any point during those years, I just happened to learn more and more, and I also learned how to know almost before even putting the memory card in the reader what settings I should import them with to make the rest of the session as short as possible and still get the result I need (want).
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So what you would need (in my opinion!) is to find your own flow, your own way to get to the end result that you want - in the easiest and quickest way.
You would also need to kind of "re-learn" the flexibility and best-use settings on your camera(s) - sometimes having more options means that you can do new stuff - or indeed just do stuff slightly differently when pressing the shutter on-camera - that means better results at the end-point: the finished image results.
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