If you're a fan of watching the Making Of extras on DVDs, you may have encountered the phrase "Check the gate" as the crew finishes a take on set.
What does that mean, exactly?
A film gate is the access to light exposure necessary for an image to be captured on film. Covered by glass, it's located in the body of the camera between the film as it rolls by, and the camera lens which controls how much light passes through the gate to the film stock.
Because of the static created by the rolling film stock, there is a continual tendency for the gate to attract dust particles or the dreaded hair.
Due to the nature of film, where a take is the culmination of an entire crew of artists and technicians, all of whom must be paid, not to mention the cost of the entire production divided by each take, each shot carries a monetary value generally of thousands of dollars.
A director must be willing to shoot multiple takes in order to get what he or she needs. There is no value in doing all of the pre-production work, then giving all the effort for the scene only to leave before everything gels.
There is always a fine balancing act between knowing how much money each take is costing, and knowing that the film must be served.
One thing no one wants to do -- shoot another take because there was a hair in the gate.
Who gets the job of checking the gate following each take?
The 1st Assistant Camera person or focus puller has this critical job.
Here's a brief glimpse at ruined footage with a rather massive hair-in-the-gate problem.
Here's a quick how-to in avoiding this manageable problem. The camera used is a super-8 camera, but every type of camera used in professional film shoots will follow a similar procedure.