In the movie Green Lantern, We saw that Kilowog was able to create a gravitational force equivalent to that of our Sun (He showed it to Hal Jordan). If creating Solar gravitational force was very-very difficult, Kilowog wouldn't have used it to train and encourage a newbie. So, I can assume that the best Lanterns like Sinestro etc. were able to create Solar gravitational force.
In the end of Green Lantern movie, we did see that Parallax was trapped by the gravitational pull of our Sun. So, logically stopping Parallax was very easy for the team of best Lanterns because they should be able to create dozens of sources of 'solar gravitational force'.
But, the problem: At that time, they didn't know that a solar gravitational pull was more powerful than Parallax. So, they tried a trial & error method against Parallax. They failed however. But, instead of re-attacking with more willpower, why did they feel fear? Isn't it like you are afraid of a coming Tiger after hitting it with a stone when you have gun?
Is this ignored for the sake of plot? Or, am I missing something?