I don't entirely understand the feature highlight tone priority.  When should I use it and what are the advantages of turning it on (or off)?





Stick –

This question is more about nuances than concrete differences.  Allow me to explain:

Highlight Tone Priority is a feature of the latest generation of Canon DSLRs including the 50d, 5d Mark II, and 1ds Mark III.  When enabled your ISO range is limited from 200-6400 vs. say 50-26,500 available on the 5d Mark II.  By limiting the ISO range and adjusting the tone curve (which has much more effect when shooting jpegs than with RAW) you can gain as much as one stop of dynamic range.

What do you lose?  You lose the advantages of shooting at ISO 50 (slowing the shutter down in brighter light, essentially for the same reasons as you’d use a neutral density filter), ISO 100 (highest amount of detail and lowest noise, useful for the highest quality images), and above ISO 6400 (very low light work).

Apparently using this mode doesn’t take much if any CPU power so it won’t slow down your shooting speed.  This is contrary to say the High ISO Noise Reduction setting.. which greatly slows your camera down when enabled and used in the range where its activated.

For general use it wouldn’t hurt to leave the Highlight Tone Priority feature enabled all the time.  However, if you forget it’s on and conditions call for ISO 50, 100, or >6400.. it could be a problem.  And remember, with RAW images you won’t see much of an improvement if any.  You get the same improvement from RAW images through proper RAW processing.

Personally I think it’s a well thought out marketing feature that only cost Canon a bit of firmware programming

I hope this helps.


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