NEW YORK ( TheStreet) -- A little over a week ago, Credit Suisse was among the co-managers of a secondary share offering by Trina Solar ( TSL) that led to a slide in shares of the Chinese solar players.

On Friday, Credit Suisse was triggering on opposite move in Trina shares, after it upped Trina from a neutral rating to outperform, and raised its price target on the stock from $18.50 to $29. Trina shares rallied by 6% at midday Friday and the Chinese solar stock had surpassed its average volume of 3.5 million shares traded by the midday mark.

In fact, the rally took Trina shares back to the levels at which they had been trading on the day before the secondary offering was announced. Trina shares had climbed to $23.40 at midday Friday. Trina shares had slid as low as $20.25 after the secondary offering was announced.

In all, the big pop in Trina shares on Friday is, in the larger perspective of its recent trading, just another up in a period of ups and downs. In mid-February, Trina shares reached over the $26 mark, and on March 12 Trina shares closed above $24. Over the past 3 months, Trina is still well down from a high over $31.

Credit Suisse's assumptions in its upgrade include a price reduction of approximately 10% in the third quarter 2010 due to the German feed-in tariff reductions, and a revenue increase for 2010 to over $1.3 billion for Trina. The Street consensus is just under $1.2 billion.

The average sales price reduction to hit the solar sector as a result of the German FIT reduction continues to be a 64,000 question. While solar management teams have forecast a 10% to 15% ASP decline in the second half of 2010, more skeptical analysts believe a 20% decline is a safer estimate.

Credit Suisse upped it shipment guidance for Trina to a level 3.4 MW above the high-end of Trina's estimate of 800 MW. While Credit Suisse upped its Trina first quarter revenue estimate by $60 million to above $384 million, it lowered Trina's first quarter earnings estimate from 79 cents to 71 cents.

However, for the full year 2010, Credit Suisse expects earnings of $2.39 per share from Trina, well ahead of Credit Suisse's previous estimate of $1.85 a share. The Street consensus for Trina is $2.13 per share.

Earlier in the week, Wedbush Securities initiated coverage of Trina at outperform. Wedbush forecast Trina revenues of $1.2 billion and earnings per share of $1.79 in 2010, reflecting an average sales price decline of 25% in 2010. Wedbush has Trina trading at 14 times 2010 earnings.

Credit Suisse, aside from expecting the 10% price decline in the third quarter, contends that pricing will be flat for Trina in the second and fourth quarters of 2010. Credit Suisse has Trina trading at 12 times 2010 earnings.

Much of the Street support for Trina comes at the expense of support for First Solar ( FSLR - Get Report) and the belief that the Chinese solar players keep getting closer and closer to eroding First Solar's price advantage.

Yet this week, two Street analysts voiced support for First Solar as well, with Kaufman Brothers and Morgan Stanley initiating First Solar coverage at a buy.

Recent short interest data from the Nasdaq indicates that negative sentiment for First Solar shares has not been increasing as much as short interest on some other solar sector underdogs.

First Solar has added more than $6 to its share price since Monday, to $116.47 on Friday afternoon. As with Trina, that's still lower than where First Solar shares were trading in mid-February, when shares went above $126.

It's been an up week for most solar stocks, but not necessarily anything more than a game of catch-up.

In fact, the only solar stocks on Friday that were trading above share prices from a month ago were LDK Solar ( LDK), ReneSola ( SOL) and MEMC Electronic Materials ( WFR).

MEMC was the only solar stock that has been steadily climbing, from under $12 at the end of February, to over $14.50 on Friday afternoon.

-- Reported by Eric Rosenbaum in New York.


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