What does a camera add to a Raw file to make a finished Jpeg version?

Question

I've used Lightroom 4 for a while now but have only ever used Jpegs, and mostly using just the basics panel and curves. I want to try developing Raw files now too.
I was wondering, compared to a Raw file what extra steps does the camera add to make a Jpeg file of the same image, essential steps that you would consider doing yourself to a Raw file in Lightroom too?
I'm aware of Noise reduction, but am a little unsure about the rest.
Many thanks.

Answer 1

Pbeck1 wrote:
my original question I feel is still partly unanswered, and that is: For a beginner to Raw editing, is there some sliders that should always be checked &/or adjusted without fail (even if you decide that no adjustment is needed).
Answer:
* white balance is critical, so it should always be considered on every photo, even if no adjustment required.
* make sure you set camera profile according to taste (and after you gain experience, you may want to roll your own).
* set lens corrections by default: CA + profile (I use a percentage of 100 for vignette correction by default, depending on lens).
* fixed default for Lr color noise reduction (Lr default is usually fine). (color noise reduction is auto-adaptive, so you really don't need to set based on ISO, although you may need to up it on some photos to get all color noise, or down it on some photos to eek out max detail.
* luminance noise reduction and sharpening should be set (initially) based on ISO range.
Then adjust the basics. If toning can't be perfected with basics, supplement with tone curve, if still some imperfect areas, touch up with locals. Use HSL if need be, and so on and so forth.
Fair enough?
PS - I consider a default of 30 for luminance noise reduction to be *extremely* high. I start at zero for low ISO shots, and ramp it up to 25 for highest ISO shots. But consider that Lr's sharpening detail slider should only be used at lower ISOs (that's just my opinion/taste - ymmv). I set detail at 20 for lowest ISO shots, and ramp it down to zero for high ISO shots (as a default - I sometimes up it or down it afterwards). If sharpening detail is kept low, you won't need so much Lum. NR.
Notes:
* color noise reduction detail matters very little except at highest ISOs, in which case you can up it to eek out more detail, usually at the expense of more noise (so it needs to be balanced with amount).
* likewise luminance NR contrast has only a very subtle effect at highest ISOs, and can pretty-much be ignored unless you are really wringing out the detail.
* luminance noise reduction detail however can be important for not losing hard-won detail in the interest of noise control - consider uping it if you need to preserve detail in birds feathers or stone... - crank it down if you just want it clean - detail not important..
What else you need to know?
To summarize:
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Lens corrections are a necessity in most cases, and you need to figure out how you like NR & Sharpening set by default. Camera profile determines the general look and feel of the photo and as such can be considered setting #1 (white balance is also setting #1 - yep: there are two #1s ;-}).
Many photos can then be adjusted satisfactorily just using the basic sliders. What's needed after that, really depends on the photo, and you...
Final thoughts are about sharpen masking. I used it a lot in the beginning, then noticed yucky artifacts / sparkling stuff scattered about..., and stopped using it entirely for years.  It's undesirable side-effects are most noticeable when sharpening detail is up (and/or sharpening amount). Moral of the story, if you keep sharpening detail (and/or sharpening amount) down, you can also use sharpen masking to keep from sharpening noise in "sky" and "skin", as another way to keep from needing so much lum. NR. Anyway, I'm using it again now, albeit very judiciously. Tip: press Alt key when adjusting sharpen mask slider.
Put another way: sharpen masking masks (disables) sharpening in some places, but not others. Whether the transitions between masked regions and adjacent unmasked regions looks like hell or not depends on how much noise is being sharpened in the unmasked regions, since it's not being sharpened at all in the masked regions. Unfortunately, the situation can not be improved by increasing global noise reduction, since that makes the masked regions smoother too (as well as the unmasked regions).
Bottom-line (imo): If low-noise is the priority over sharpening, then keep sharpening amount and detail low and use masking. If sharpening is a priority over over noise, then leave masking off and crank up sharpening til heart's content. If both sharpening and noise are priorities, there is no choice but to sharpen and/or noise reduce via locals, since using sharpen masking in conjunction with high sharpening (detail and/or amount) on a noisy (or even semi-noisy) photo, looks like cr@p (yes: that's just my opinion), regardless of global lum. NR setting.
PS - Some people use sharpen masking with sharpening detail (and/or sharpening amount) up too and don't know what the heck I'm talking about - YMMV...
Although I use zero sharpen masking by default, some people use light sharpen masking in default settings, and some people use heavy sharpen masking as default. Worth considering how much of it you tend to like...
UPDATE:
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Settings you usually don't have to mess with, as a beginner: and why.
* Camera calibration color sliders: white balance suffices.
* Effects: most are "advanced" / optional (although you may want to explore post-crop vignette amount as your first foray).
* Lens corrections: you need chromatic aberration at a minimum, and some profile-based correction by default is usually good, but the rest are "advanced".
* Detail (covered above).
* Split toning: "advanced".
* HSL: "intermediate".
* Tone Curve: consider using the parametric curve sliders, if you are beginner; point curve & channel curves are advanced; moving the parametric range-changing doo-hickeys: let's call that "advanced" too.
* Locals and such can be considered not for begginers, but they will need to be used too at some point for optimal results. I mean, even beginners need to get the red-eye out sometimes, or kill dust spots... And you can get by without gradients or paint for a while, but not for long...
Have fun,
Rob