AS THE UNREMARKABLE but mostly mellow 59th edition of the Cannes Film Festival quickly passes into history, a few lessons can be drawn from the event that may prove useful to filmmakers hoping to one day bring home a Palme from the Palais.

  • Don’t accept an invitation to the festival if your film’s not ready.

Such advice was not heeded by the maker of “Southland Tales,” arguably the competition’s biggest fiasco. As festgoers came to understand the situation after the fact, director Richard Kelly and the producers intended to keep editing and refining the sprawling, ambitious political fantasy until September, when they hoped to premiere it at the Toronto Film Festival. However, the film’s Paris-based foreign sales company, Wild Bunch, urged Cannes artistic director Thierry Fremaux to take a look, and he invited the film as it was. Ill-advisedly, as it turned out, the filmmakers accepted; the result is a gravely wounded picture that will now be recut into a new version that may well debut in Toronto.

The last time something like this happened was two years, when the Japanese financiers of Vincent Gallo’s notorious “The Brown Bunny” more or less insisted that he submit his then-overlong film before its time. His subsequent recut, shorn of a half-hour, was subsequently shown (in Toronto, initially) and was better received. The same could happen to “Southland Tales,” but it’s awfully hard to dig (or cut) yourself out of such a deep hole.

Filmmakers would be well advised, then, to avoid the temptation of an invitation from Cannes or any other festival before they think their film is ready for serious scrutiny. One Cannes vet cognizant of the principle this year may have been Steven Soderbergh, who, despite Fremaux’s enthusiastic invitation, decided to withdraw his black-and-white post-WWII drama “The Good German” for further refinements. After all, if your work is good, there is always another festival right around the corner that will be happy to show your film.

  • You’re in good company if you’re rejected, especially if your last name rhymes with Prix.

In each of the last two years, the Cannes selection committee has received a retrospective black eye come September when the Golden Lion at the Venice Film Festival has gone to a picture Cannes rejected; last year it was “Brokeback Mountain,” and the year before that it was “Vera Drake.” Cannes organizers later offered lame excuses, such as allegedly having only seen part of Ang Lee’s cultural touchstone, but insider word is that they simply didn’t like “Brokeback” and that Mike Leigh was a victim of the fest’s worthy but ineptly applied effort not to automatically show virtually any film just because it was made by a long-favored auteur.

No doubt Ang Lee and the Focus guys were distressed by their rejection (Mike Leigh, for his part, told the Cannes bunch they could go jump in the Mediterranean when he accepted his Venice prize), but there is a theory that Cannes actually did them a favor by rejecting “Brokeback.” First, the Cannes critical reaction might not have been as hugely enthusiastic as that which greeted the film in September; a degree of negativity could have dented its reputation at the outset. Second, even if it had scored raves in Cannes, “Brokeback” might have peaked too early by premiering in May. As things turned out, the film rode an ever-cresting wave from Telluride, Venice and Toronto through the critics’ awards all the way up to a couple of weeks before the Oscars, when “Crash” obviously overtook it. But it was a great run that might still have turned out well with a Cannes start but wouldn’t have happened the same way.

As for Venice, it will never live down having rejected Clint Eastwood’s “Unforgiven.”

  • Don’t give up on the Palme.

Some observers detected a note of disappointment in Pedro Almodovar’s attitude as he accepted what could be construed as a consolation screenplay prize this year for “Volver,” which had topped the critics’ polls throughout the fest and was the only film to win two awards (the other was for its ensemble of actresses). But Spain’s modern master should take heart from the fact that he lost to Ken Loach, whose Palme d’Or-winning “The Wind That Shook the Barley” marked his eighth film in the competition but first Palme.

Loach’s new film isn’t a masterpiece or the best of his career, but it’s a strong, worthy picture that no doubt got extra credit by virtue of its director’s track record. It took some other notables, including Lars von Trier, a few tries to win, while Eastwood has been up to bat five times in Cannes without a homer.

  • Try really, really hard to make a great film within the next 12 months.

Next year is the 60th anniversary of the Cannes Film Festival, so Fremaux & Co. will be scouring the earth to find the best possible films to fill out the lineup. Do your best work on your next picture and you could find yourself taking home a prize and getting a big bisou from Catherine Deneuve.

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