With HTP set to 'On' the exposure remains the same, but (on my Canon cameras) ISO (conversion gain) is lowered by 2x. This adds 1 stop to the headroom in highlights.
When a camera is set to ISO 400, the maximum value in raw is about 14,000. HTP lowers the conversion gain by the factor of 2, and the previous reading of 14,000 becomes 7,000 - that's an extra one stop.
You can take 3 shots under the same light with the same shutter speed and aperture setting, one with ISO set to 400 and HTP set to 'Off', next with ISO set to 400 and HTP set to 'On', and the last one with ISO set to 200 and HTP set to 'Off', and compare them, looking at raw histogram. You can also use any file exchange server (Dropbox, Google Drive, WeTransfer are some of the free ones) to upload the raw files and send us the links to downloads.
With HTP set to 'On' the
With HTP set to 'On' the exposure remains the same, but (on my Canon cameras) ISO (conversion gain) is lowered by 2x. This adds 1 stop to the headroom in highlights.
When a camera is set to ISO 400, the maximum value in raw is about 14,000. HTP lowers the conversion gain by the factor of 2, and the previous reading of 14,000 becomes 7,000 - that's an extra one stop.
You can take 3 shots under the same light with the same shutter speed and aperture setting, one with ISO set to 400 and HTP set to 'Off', next with ISO set to 400 and HTP set to 'On', and the last one with ISO set to 200 and HTP set to 'Off', and compare them, looking at raw histogram. You can also use any file exchange server (Dropbox, Google Drive, WeTransfer are some of the free ones) to upload the raw files and send us the links to downloads.