In Canons Digital Photo Professional, one can see if the picture was taken with Highlight Tone Priority or not, but in Lightroom one cannot. Is there a way (plugin/hack/...) so that I can get to see this also in Lightroom?
Thomas Knoll, Oct 18, 2008 1:15 PM
> Eric: No. How would knowing this information improve your workflow?
It has the same effect on the workflow as knowing the shutter speed or aperture, or knowing if the flash was fired or not. One might, on the one hand, argue that once the picture is taken, knowing the shutter speed has no effect on the result. On the other hand, when analyzing the results of sharpness, bokeh, aberrations etc, it is very valuable to know the shutter speed and aperture!
Likewise, it is very important to know if HTP was enabled or not when analyzing highlight and shadow performance, so one can learn from results. This is because (as I am sure you already know) HTP can have a profound very positive effect on the highlights, especially in combination with Recovery, while (depending on the ISO-setting) it somewhat degrades the noise in the deepest shadows.
We learn from results, we decide parameters based on historical results. HTP can be as important to control as aperture is. And, if I compare results from different cameras, say 40D and 50D, it becomes meaningless if they use different settings for HTP.
PS: For those who might not know: HTP affects RAW just as much as JGP.
>Lee: As far as I know, it only affects the raw data by under-exposing the image. It's the same as -EC. In other words, it's only a change to metering unless you shoot in JPEG.
Curves are involved, but in different ways for HTP and Nikons Active D-lighting.
Not the same as -EC (as far as I know). Among other places, check out:
(Although the latter does not say so much about the tone curve, since it basically only mentions the *principle*, namely underexposing [in parts of the range of] the image.)
>First: Is it "pure" exposure compensation? So it is in every aspect equivalent to -1 stop exposure in the camera and then +1 stop exposure in LR?
The RAW data is really simply underexposed with about a stop. The camera then applies some curves and some exposure compensation to create the jpeg, however nothing happens to the RAW.
>Second: Nikons Active D-lighting is said to be "similar", but with some differences. Are these two methods exactly the same, or what is the difference?
Nikon's method is more complex. It actually applies a dynamic range reduction technique (called HDR by some folks) in the camera that is similar to applying some shadow fill and some highlight recovery. This cannot be done by simple curves as the shadows are treated differently than the highlights. At the same time, the RAW data is completely unaffected except for the about 2/3 stop underexposure it applies. This only affects the jpeg preview and it affects what Nikon's capture program would do with the data.
I thought I had a pretty good idea what it does -- now I now better! Thus, in raw data, in LR, both HTP and Active D-L amounts to a simple pure underexposure with no other curves applied, 1 stop for Canon (approx(?)) and 2/3 for Nikon!