3:2 Pulldown Explained
Why reverse 3:2 pulldown?
Reverse the process? Am I kidding? Sadly no. There are a few DVDs available that come as progressive scan rather than interlaced, but not many. When you consider the fact that the majority of people are watching DVDs on NTSC televisions and do not have the luxury of seeing them on the big screen from a front projector, it makes sense. It's okay to think about how much better our world would be if we all had giant progressive scan images from projectors in our homes, but it doesn't solve our problem. What does solve the problem is reverse 3:2 pulldown or de-interlacing.
"Reverse 3:2 pulldown" is the process of finding the original film frame. It would be easier to find the original frame if the new frames were not interlaced. However, as we mentioned before, we created extra video frames, which are interlaced, by combining two different non-interlaced film frames. Simply displaying each video frame in progressive scan will create 'jaggies' and other distortion.
Luckily, new progressive scan DVD players come with the de-interlacing built-in. Basically, the DVD player uses an MPEG decoder that knows which frames will create images with the least distortion and puts them together for you. Some DVD players will do this better than others, so you will need to do some homework if you are a stickler. For most of us, the picture is so much better than NTSC a few glitches won't matter.
Some people may think that a simple line-doubler will solve this problem. But without reversing the 3:2 pull down process, a projector with an internal line-doubler will try and 'double' or de-interlace frames that are inconsistent. What you will see is a periodic jumbled mess of confused images with artifacts, and artifacts do not make for film-like images.
So in your quest for the best image for your money, what is the easy answer? Get yourself a progressive scan DVD player with 3:2 pulldown detection and use your projector's component input. You could spend the money on a projector with the reverse 3:2 pulldown as well, but getting it in the DVD player will cost you less, and it is a little more efficient because the conversion process is taking place at the source. Using your component input will bypass the internal circuitry of your projector and show the progressive, film-like image in all its native glory.