Our post house thought it might be a bad HMI light, camera malfunction, or a lab error. Without knowing the exact source of the issue, it made it harder to determine the best fix.
And one of the largest problems was that the flicker was not noticeable until over a year after filming. Why was that? We never projected the film on the big screen until we were working in a Digital Intermediate. Throughout editing, we watched the film on a tiny screen and couldn't detect the flicker. Once on the big screen though, you could definitely see it and we worried the film would never pass Quality Control once we sold it. Now what? (as my blood pressure rose)
Well, first, we hoped the flicker could be captured by a certain algorithm and then removed. Unfortunately, our flicker was not moving at a constant rate. Instead it was fluctuating at many different speeds, making it impossible to capture easily and remove. This was when we knew we had a big problem.
I then contacted our insurance company. I was very nervous about filing a claim more than a year after filming but the problem obviously occurred during production. I hoped I wouldn't run into any problems. Sure enough, the insurance company's biggest complaint was the amount of time between filming and the detection of the problem. I explained what happened and had three post houses confirm that it happened during filming. That's all I could do. And the insurance company eventually agreed to honor the claim. (blood pressure began easing)
The next step was getting quotes from post houses who could fix the problem. However, this was not a simple fix nor was it going to be cheap. I went to four different places and luckily one referred me to the wonderful team at Identity Studios in LA. These guys are miracle workers. None of the other post houses could offer an affordable fix that would even work well. Not because they weren't capable post houses -- the others just didn't have the specialized experience with this kind of problem.
Identity, on the other hand, had experience with these kinds of flickers and they offered a near-perfect fix and an affordable quote. When I say affordable, I mean affordable in the post world of costs. It was still very expensive! I could have bought a really nice car with what it cost.
I guess the moral of this story is to not give up. If you see a problem that seems impossible to fix. Keep trying until you find a way. Just like we found Identity, you will find your miracle worker too.