What are the pros/cons of the high-ISO noise reduction feature on D90?

Question

So my D90 offers "High-ISO Noise Reduction". Sounds like a good thing, but obviously there must be a cost of some kind. The settings are "Off", "Low", "Normal", and "High", and the default is "Normal".

What are the pros and cons of using this feature? Why not always set it to "High"? Or, should I be turning it off?

Answer

The pro's are self-evident:

• Lower noise on high-iso

The biggest con:

• Loss of detail

The high-iso noise reduction might remove detail mistakenly. While newer camera algorithms have gotten better at it, it's still not fool proof.

The settings between Off, Low, Normal and High dictate the amount of tolerance used for the setting, which affects the amount of detail that might be lost.

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