The indices had a definite down session today, but a late, sharp rally just in the last 20 minutes or so brought them way back and substantially off the lows to pare the losses.

The day started out with a gap down. The indices went sharply lower in the morning, particularly on the SPX. A rally back failed at resistance on the NDX and didn’t get even close to it on the SPX. Then they made lower lows and session lows by mid-afternoon. They began to pullback but retested late in the session, only to come on again in the last 20-25 minutes with a charge, particularly in the last 5 minutes, closing near resistance.

Net on the day the Dow was down 65.63 at 8675.24, the S&P 500 down 12.98 at 931.76, and the Nasdaq 100 down 4.87 at 1475.44. The Philadelphia Semiconductor Index (SOXX) dropped 6.11, more than 2 percent.

The technicals were negative by 2 1/2 to 1 on New York and by about 3 to 2 on Nasdaq. Up/down volume, however, was much more severely negative, particularly on New York where just 163 1/2 million shares traded to the upside with 1.15 billion to the downside, about a 7 to 1 negative ratio. Nasdaq was just 7 to 4 negative on total volume of just under 2.3 billion traded.

TheTechTrader.com board was mostly negative, with several point-plus losers. On the plus side, there were 3 point-plus gainers.

Portfolio position OncoGenex Pharmaceuticals (OGXI) jumped as high as nearly 22 at one point, but closed at 20.65, still up 1.81 today.

DG FastChannel (DGIT) after completing their secondary jumped 1.68 to 21.50, and Apple (AAPL) advanced 1.46 to 140.95.

Several other junior biotechs had fractional gains, including Celldex Therapeutics (CLDX) up 59 cents at 10.92. Dendreon (DNDN) had a strong session, closing at the highest level in nearly 2 months, at 24.90, up 83 cents, on 5.6 million.

On the downside, loss leaders included the ag/chemical stocks. Potash (POT), down 5.73 at 110.66, and Mosaic (MOS), down 3.53 at 53.44, led the way.

Some of the ETFs were weaker today. The U.S. Oil Fund ETF (USO) was down 1.36 to 36.25, on weaker crude. iShares MSCI Brazil Index ETF (EWZ) lost 3.07 to 54.23, and the iShares FTSE/Xinhua China 25 Index (FXI) lost 70 cents to 38.02.

Other losses of note, financials were weaker, with Goldman Sachs (GS) down 98 cents to 142.15, Wells Fargo (WFC) 26 cents to 24.13, JP Morgan (JPM) 52 cents to 32.98, and Morgan Stanley (MS) 37 cents to 29.72.

Junior solars were hit with profit-taking . Canadian Solar (CSIQ) lost 80 cents to 12.57, and STP was down 88 cents to 16.20. Yingli Green Energy (YGE) at 13.03 was down 66 cents.

Stepping back and reviewing the hourly chart patterns, they moved lower in the morning, bounced mid-morning, and then made lower lows in early afternoon before a late afternoon sharp rally brought them substantially off the lows, with key support in the 922-25 zone on the SPX.

We’ll probably know by tomorrow if that was significant or not or whether it was just late short covering.

Harry Boxer is a technical consultant to many Wall Street hedge funds and large institutional traders, and author of TheTechTrader.com.