With HiDef altogether, the ability to have everything in the frame tack sharp is not, in fact, a good thing.

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This is a very fast camera in every respect (bar an occasional lag writing RAW files to memory) with a tack-sharp, super-fast lens, pleasingly fast autofocus, a great, bright screen, and rock-solid feeling controls that are right where your fingers need them to be.

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No other compact economy car outside of a Mini Cooper offers as much stick-and-rudder fun as the 3: The steering (hydraulic, with an electric pump) is tack-sharp and precise, with almost no torque steer and a gratifying heft that gathers as you turn the wheel.

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Ninety years old and still sharp as a tack, his tales of self-induced disasters are worth recalling as we live through yet another.

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Michael Merzenich, a UC, San Francisco professor, has developed computer games that might help Alzheimer's patients improve brain function (" Sharp As A Tack" ).

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That brought a sharp change of tack a year ago, after the expulsion from Georgia of several Russians accused of spying had raised the temperature again.

ECONOMIST: Snap elections will not end the woes

After years of virtuous pleading for more decisions by majority vote in Euro-councils, the chancellor shocked his partners by what seemed like a sharp change of tack.

ECONOMIST: Germany