Originally posted by WMBP I don't think anybody has offered an answer to the question I asked earlier: does this feature in the K20D do anything that I can't do myself, by exposing to the left in order to avoid clipping, and then bringing the exposure back up on the computer?
Will
No, there is no magic, just convenience. If you shoot RAW, and have a capable RAW editor, and take care in your methods, you can accomplish what the EDR offers you and more. Even if you don't normally use Lightroom or Photoshop ACR, the ACR engine does a terrific job of restoring clipped highlight information...As long as there is at least one of the RGB channels that is NOT clipped, then ACR can restore the highlight info.
Still best to back off the exposure to the left so you don't clip anything, though. You don't want to go too far left, because when you bring up the shadow detail, or try to, you'll get a lot more noise and banding in the shadows. So expose left enough so you just barely aren't clipping any highlight detail, or just have a few dots blinking (turn on the exposure warning in the preview) Remember that your preview in the LCD is based on a JPEG conversion, and does not represent the actual RAW file, but the JPEG processing parameters you have selected.
So, expose left enough so you don't blow or completely clip your highlights, but careful not to move more than necessary into the shadows . Increase your ISO (which is what EDR does). Increasing the ISO should give you some more room in the shadow area. Bracket if it is a still scene, or not if it is a moment to be captured.
Then process your RAW file. In RAW conversion, (at least ACR/Lightroom) take the default contrast from 25 to 0 to start with, you can bring this up later after you get the most range out of your photo, contrast reduces the range so that a flat photo is more dynamic, but you are starting here already with an overly dynamic image. Also make sure that your point curve (again in ACR/Lightroom) is set to medium contrast or even linear, medium looks better than linear but if it is a tricky shot you might have to use linear, avoid strong contrast as this just pushes more into both over and under exposure.
First of all, obviously, make sure your white balance is the way you want it before making the following adjustments..
Next bring up the exposure just so it isn't clipped or just barely clipped, use the recovery slider to the point that nothing is clipped (hold down the option key while you move the exposure and recovery sliders to see where clipping starts) Then back down on the "black" again holding down the option key so you can see what is being clipped. If there is any black clipping, then you can use the shadow slider to bring life back into those areas. if you have any room left over on either end (more room to go with the exposure and recovery sliders, as well as the black and shadow slider) and you want a little more punch, you can bring some contrast back up, as you do so,, you will need to check the exposure clipping and black clipping again and adjust those or give some more push to the recovery and shadow sliders.
The last tone adjustment will be the brightness, and this is to taste and affects the midtones, so use this to give the image a more high-key or low-key look. Then with your input sharpening, don't go crazy sharpening all over the board, but you can sharpen so that you actually can perceive more highlight detail, just make sure that your masking is set to cover the shadow areas (again in ACR/Lightroom) holding down the option key while looking at the image at 100% will show you were the mask (dark area) is applied and thus no sharpening there, so adjust the masking slider so that it covers your shadow areas and leaves your highlight areas open, then your sharpening will only affect the mid and high tones, giving the appearance of more detail in those areas, (and less blown looking) while not increasing your noise in the shadows. Then finally, if there was a lot of noise picked up in your shadow area when that got adjusted the way you want it, is to use your favorite noise plug-in in your favorite photo editing app (I use noise ninja in Photoshop).