I'm trying to recreate the effect used in the beginning of this video below. I want to make something like the colored football players seen here, but for hockey. Can anyone tell me how they did that? or suggest a good filter that can imitate the 70's feel?
I would start with keying the playes, this could be done using a green screen or playing with luminance keying and rotoscoping to cut out a silhouette and add a color fill. The next bit is the visual echo, and back then it would have been most commonly done using an Abekas DVE or ADO, or a couple passes using a Pinnacle Alladin, or a Video Toaster, it is a DVE effect called "trails" or something similar.
I think you can imitate this a couple of ways today. In FCP, there may be an effects plug-in from one of the-third party suppliers like Nosie Industries or Red Giant, etc. to do a trails/afterimage trail. This might also be possible to do using replicators or particle-based replication in an AfterEffects comp or Apple Motion composite. You would have precision keyframed control of the effect in that composite.
A super-cheesy way to do it would be to roll the keyed player shots on a TV monitor with a camera set up in front of it, and set up visual feedback from a camera shooting the monitor, into the switcher rolling the source tape.