By Tom Westbrook

SINGAPORE, Sept 19 (Reuters) -The dollar bounced, long-dated bond yields were up and Asian stocks mostly rose after the U.S. Federal Reserve began its easing cycle with a large rate cut, though it tempered that with a balanced outlook as it seeks to keep the economy ticking over.

The S&P 500 .SPX hit a record high overnight, before closing slightly lower. Futures ESc1 rose 0.6% in the Asia day and Nasdaq futures NQc1 were up 0.9%. Japan's Nikkei .N225 jumped 2% and Australian shares .AXJO hit a record high. .T.AX

The Fed lowered its window for the benchmark policy rate by 50 basis points to 4.75-5%, where markets had been leaning before the decision. The dollar immediately hit a two-and-a-half-year low on sterling, but then recoiled sharply.FRX/

It was up nearly 1% to 143.55 yen JPY=EBS early on Thursday and well off lows on the euro at $1.1081.

Ten-year Treasury yields US10YT=RR have climbed nearly eight basis points from a day earlier to 3.719%, while gold XAU= shot to a record high just shy of $2,600 an ounce, before easing back to steady at $2,559. US/GOL/

The Fed's cut is expected to support spending and the U.S. economy.

"The key was never going to be about 25 or 50, it's all about the path forward and I think they've outlined a view where the economy is still doing pretty well," said BNZ strategist Jason Wong in Wellington. "This wasn't a panicked 50 (bp) cut."

Policymakers' adjusted their median rates projection downwards, compared with their outlook in July, but Fed chair Jerome Powell emphasised the next moves would be data driven.

"I do not think that anyone should look at this and say, oh, this is the new pace," Powell told reporters after the outsized cut was announced.

"We're recalibrating policy down over time to a more neutral level. And we're moving at the pace that we think is appropriate, given developments in the economy."

MSCI's broadest index of Asia-Pacific shares outside Japan .MIAPJ0000PUS was down 0.4% in early trade, pressured as South Korean markets .KS11 returned from holidays with heavy falls in the chipmaking sector following a downbeat Morgan Stanley note.

SK Hynix shares 000660.KS tumbled 9.6% and Samsung 005930.KS fell 2.6%. Hong Kong's Hang Seng .HSI rose slightly while the mainland benchmark CSI300 .CSI300 fell 0.4%. Oil prices fell and benchmark Brent crude futures LCOc1 were last down 0.3% at $73.42 a barrel. O/R

Around the region lower U.S. rates in theory leave room for emerging markets to cut their policy rates and support growth.

Bank Indonesia had already moved a few hours before the Fed, with a 25-basis-point cut on Wednesday. Chinese bond yields fell in early trade on Thursday in anticipation of fresh easing from Beijing to prop up China's increasingly sluggish economy.

The Bank of England meets later on Thursday and is seen holding rates at 5%, especially after inflation figures showed services inflation picked up in August. The Bank of Japan sets policy on Friday, and is expected to stand pat but line up future hikes, perhaps as soon as October.

Editing by Shri Navaratnam

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