What is it you Neuro and TrumpetPower not understand ?
Well, I'd like to say I don't understand your rudeness and steadfast refusal to admit when you're wrong, but I'm afraid I understand them all too well.
You say read your earlier comments? Ok.
I read that you stated HTP halves the amount of light. Do you believe that?
The data recorded by the sensor (and, presumably, written to the raw file) is identical for ISO 50 and ISO 100; all that's changed is the meter is told to overexpose by a stop and the raw processing engine is told to underexpose by a stop.
no they are not
At 100iso with the same metering the sensor charge is under 100 % and at the read out =before overload and clipping
with 50iso your double the time or open up the lens 1 stop and therefore blow one stop of highlight.
I read that you stated that ISO 50 changes shutter speed or aperture by one stop. Do you believe that?
put your camera in front of a white wall, see what you get for values at 100 iso then compare with 50iso
you will find that the exemplel 1/60sec f-5.6 will be with 50iso 1/60 sec f-4, 0 = 1 stop richer exposed compared to 100iso and you lose 1 stop of high light
I'm talking about the RAW file, not the metering. Unless I change the aperture or shutter, or let the camera do that (in an auto exposure mode like Av or Tv), there will be no difference in the sensor-derived image data between ISO 50 and ISO 100. Both are ISO 100 exposures, tthe ISO 50 data will merely be pulled down a stop by the RAW engine.
As for HTP, it's possible we're saying the same thing in different ways about the what (HTP ISO 200 is actually being underexposed at ISO 100 then brought back up). But where you seem to be wrong is the when - your contention is apparently that the data are altered on the sensor. Perhaps I misunderstand you, and you are referring to the actual ISO 100 exposure when ISO 200 is set in camera as that alteration. But what I'm saying, and TrumpetPower is saying, is that the HTP ISO 200 exposure RAW file is the same as an ISO 100 (non HTP) RAW file, and your statement that, "you halve the number of electrons" indicates you believe the RAW file is different. If you mean relative to an actual ISO 200 (non HTP) exposure, fine - but that's not what we've been talking about.
If you mean ISO 100 RAW is different than HTP ISO 200 RAW, that's wrong, and if you think that's what the page you linked and keep on re-quoting is saying, you're misinterpreting it. It states: "In post-processing, the image data can be brought back up while preserving the highlights with a modified tone curve...." Post-processing, not the RAW data file, as your statement about halving the number of electrons indicates. There is no change in the number of electrons between ISO 100 and HTP ISO 200, both are ISO 100 exposures, same number of electrons, just handled differently in post. If you don't understand that, perhaps you should re-read those links of yours.