Ralph Acampora is one of Wall Street's most-respected technicians. So what does he make of the recent cases for a mega-downturn made by analysts such as Abigail Doolittle, who calls for a 50 to 60 percent "correction" based on her technical analysis?

"I hear that and I see what they're talking about, but these people have been saying that for a long time," he said Thursday on CNBC's "Futures Now." "And honestly, if you look at the technicals as I do, there's just no way I can make those downside targets."

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Doolittle has long been calling for some sort of market crash or other for at least four years (see, for instance, the May 2010 edition of Doolittle's "Peak Theories Research" in which she said the S&P will "correct severely," or the July 2011 edition in which she notes that she has an S&P 500 target of 425).

So far, Doolittle's calls on the S&P have not been proven. And it's not that Acampora doesn't think the market could falter.

"If you have a shorter time parameter—let's say, the next weeks or a month or two—it could slow down," he said.

In terms of a correction, "I could see 5, 6, 7 percent maybe. But in the order of 20, 30 percent? No. No way. No, I don't see it. No, ma'am."

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Acampora himself has turned considerably less bearish of late. Back in May, he told "Futures Now" that the S&P would drop 10 to 15 percent by October. But the director of technical research at Altaira made it clear on Thursday that he is now very much a bull.

"If you're long-term like I am—and I mean really long-term, meaning looking out 10 years or so—I think there's a lot left" in the rally.

—By CNBC's Alex Rosenberg

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