Quote Originally Posted by Johnny Rasmussen
You mentioned you did not shoot with HTP on because of increased shadow noise. Is it really that visible? I have not shot with the 7D but it is hard to see any difference in files from the 50D.

It's rather situationally dependent. I have seen it in some shots, not in others. I suspect it's a combination of factors. Even Bob Atkins stated (from the article you linked), "Looking closely at images shot with Highlight Tone Priority turned on and off, there is an increase in the shadow noise if you look closely enough." As I stated, I don't usually use it. But, I do use it occasionally (in fact, it's one of the settings I put in My Menu) in situations where looking at the scene I expect issues from blown highlights at the exposure I plan to use.


Daniel summarized it nicely in a previous discussion on 'tweener' ISO settings:



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Quote Originally Posted by Daniel Browning
It's a pretty minor effect by itself. Just like HTP is a pretty small effect, and ALO is a pretty small effect. But when you start combining all these small factors, it results in a big factor. For example, ISO 250 by itself may not increase shadow noise enough to notice. And ISO 200+HTP by itself may not either. But combine 250+HTP and the result will be much more noticeable: the shadow noise is as bad as ISO 640. Add ALO into the mix and you can get people wondering why their ISO 250 shot looks like ISO 1600.
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