Originally posted by biz-engineer Hello Guys,
I've read you comments and greatly appreciate to have your suggestions and point of view. I think Steve understood my question correctly, but I'm not sure. Let me give you a bit more info.
I'm currently reading a book from Bruce Barnhaus, chapter #9 about film development and contrast control. He says that:
- changing the development time allow shifting of the high lights but has little effect on the shadows
- changing exposure better allow to shift the shadows.
In the past, with the K-3 , I tried to boost the exposure then decrease levels with the same amount in order to decrease noise, then compared the pictures. Result: yes noise was reduced, but contrast was reduced as well.
Now, while reading the book, I compared again the effect of changing exposure during the shot versus changing exposure during development using the K-3 raw converter. But I expected that adjusting the exposure at raw to jpeg conversion would be producing the same result as adjusting the exposure of the shot. But it's not. So either sensor response non linear (similar to film, sensitivity decrease as light increases) , or the raw converter curve is non linear. If the sensor is not linear in the high light zone (like film) , this is very important , this means the contrast of your base raw image will change with exposure, and of course you can correct later in post processing (as some contributors pointed out here above), but better start with a good raw file. I should share two pictures to illustrate.
Google dodge and burn. That is what the film developers called the technique. I think some software provides functions with the same name and same effect.
I have experienced what you describe. But as long as there isn't any over exposed or blown highlights, it is a matter of finding a base curve that brings back the pop. A straight raw to jpeg conversion will be flat and lifeless to our eye, so the tones and luminosity are adjusted based on a curve. Every camera manufacturer has their own, and we can recognize a Canon shot for example. Your software has predefined curves that you can apply, or you can define your own. I'm not familiar with lightroom, but more than likely it provides multiple ways to do the same thing. Contrast, brightness, saturation sliders, or tone curve editors, or selecting from a list of presets. I have found settings that work in most cases and adjust for the specific image.
It may also mean that on the higher exposed shoot you are clipping one of the color channels. Even if that isn't the case the applied effects may need to be stronger.