40D - Highlight tone priority - any opinion out there

I am researching whether this is usefull or not see: http://www.bobatkins.c​om …non_eos_40D_rev​iew_6.html

See the highlight tone priority bit. For one you need to be at ISO 200 or higher.

The effect of HTP is

1. reducing the effective ISO by one stop (that's the reason it can not be selected @ lower than ISO 200).

This is in effect an underexposure by one stop.

Note, that the displayed ISO number contains "o" the lower case letter) instead of "0", the digit.

2. When creating JPEG in camera: the intensity gets adjusted by +1 EV, but not uniformly: the highlights are kept back.

3. In case of raw: recording this fact as a flag in the raw file.

When processing the raw by Canon software, the intensity gets adjusted by +1 EV, but not uniformly: the highlights are kept back.

When processing with LR/ACR, the intensity gets adjusted by +1 EV, just like an "exposure" adjustment, nothing else. To achieve the same effect as with DPP, one hase to use for example the "recovery" adjustment.

The embedded JPEG is treated than in #2.

That's all to it; nothing magic.

Panopeeper wrote in post #6739140
The effect of HTP is

1. reducing the effective ISO by one stop (that's the reason it can not be selected @ lower than ISO 200).

This is in effect an underexposure by one stop.

Note, that the displayed ISO number contains "o" the lower case letter) instead of "0", the digit.

2. When creating JPEG in camera: the intensity gets adjusted by +1 EV, but not uniformly: the highlights are kept back.

3. In case of raw: recording this fact as a flag in the raw file.

When processing the raw by Canon software, the intensity gets adjusted by +1 EV, but not uniformly: the highlights are kept back.

When processing with LR/ACR, the intensity gets adjusted by +1 EV, just like an "exposure" adjustment, nothing else. To achieve the same effect as with DPP, one hase to use for example the "recovery" adjustment.

The embedded JPEG is treated than in #2.

That's all to it; nothing magic.

Many thanks, did some test shots and I can see the differences. Will look into the technicals you mentioned. This helps.