* Nikkei rises 0.8 pct, Topix up 0.4 pct * Nippon Steel jumps on price hike report * Investors focus shifts to corporate earnings By Dominic Lau and Tomo Uetake TOKYO, July 23 (Reuters) - Japan's Nikkei average advanced on Tuesday morning, reversing early losses, with traders citing opportunistic buying by investors in large cap names as attention shifts to the earnings season. By the midday break, the benchmark Nikkei gained 0.8 percent to 14,770.27 after falling as low as 14,549.06 in early trade. "People, especially long-onlys, are not overweight in Japan. As long as the markets are stable - the U.S. market is looking good, China is not falling off the cliff, there will be opportunistic buying here and there," a senior dealer at a foreign brokerage in Tokyo said. Nippon Steel & Sumitomo Metal Corp climbed 3 percent after the Nikkei newspaper said the steel company and Toyota Motor Corp have agreed to raise the price of steel sheet for April-September by some 10 percent from the previous six-month span on a weaker yen. The report lifted other steel makers, with JFE Holdings Inc advancing 3.3 percent and the steelmaker sector adding 2.6 percent to become the best sectoral performer. Index heavyweight SoftBank Corp jumped as much as 2.6 percent in the morning ahead of its President Masayoshi Son's speech at a seminar in Tokyo. The stock was up 0.8 percent after the morning session. The broader Topix index gained 0.4 percent to 1,221.40 in light trade, with 33 percent of its full daily average for the past 90 trading days. "What's happening in the market is that it's just sort of rebounding from yesterday's unexpected weakness following the election. We are kind of back to pre-Friday levels," another senior trader said, adding that his brokerage had more sell orders than buy. Prime Minister Shinzo Abe's ruling Liberal Democratic Party and its coalition partner won decisively in the upper house election held on Sunday, opening the door for him to pursue tough reforms required for a sustained economic recovery. The government's fiscal expansionary policy, coupled with the BOJ's aggressive monetary stimulus, have helped push the benchmark Nikkei up 42 percent this year. The benchmark was holding above 14,596, the 61.8 percent retracement of its slide from May 23 to June 13. In terms of valuations, Japanese equities carried a 12-month forward price-to-earnings ratio of 14.7, rebounding from a near six-month low of 13.2 touched in late June though still below a three-year high of 16.3 hit after the index reached a 5-1/2 peak on May 23. Analysts said the prospect of the Nikkei building on its gains after the election will depend on whether Abe can implement drastic structural reform, while the latest corporate earnings results would also provide further evidence of the prime minister's push to revive growth. According to data provider Markit, publisher Kadokawa Group , precision motor maker Nidec Corp and measuring instruments maker Advantest Corp were among the most shorted stocks in Japan, ahead of their quarterly earnings.