I'm starting to get the blue ray bug and I need help understanding some of the technicals of the video output before I pull the trigger.

I've got a Sony Ruby projector which I understand will only accept 1080p/60 on the HDMI input. I understand that blue ray players output 1080p/24 which won't work with my Ruby. I think I've also seen that some players support 1080p/60, but there's this problem they are calling judder? What's judder?

BTW, I currently have an Oppo 981 connected to the Ruby via HDMI which must be running at 1080p/60 and the picture looks pretty darn good.

I've also read that the DVI input on the Ruby will support 1080p/48. Are there any players that support 1080p/48?

Basically, I need help understanding which player I can hook up to my Ruby and get the best results. I'd really like to stick with my optical HDMI cable and either use the HDMI or DVI input on the Ruby. Does anyone have a good explanation of the whole 24/48/72/60 Hz problem?

Typically, 1080p output is 1080p/60, due in large part to the fact that so very few displays support a 1080p/24 input. The 981HD's 1080p support is 1080p/60. Blu-ray and HD-DVD are encoded at 1080p/24 for film sources (the 24fps nature of film makes it a natural choice), but many players will still only output 1080p/60 - in fact, several players have only received support for 1080p/24 output via firmware updates, and others don't support it at all.

To produce a 1080p/60 output from a 1080p/24 source (or any other film-based source, including many DVD's), the player has to properly carry out a "3:2 pulldown" procedure (three frames of video output for every two frames input). There is a good article at The Digital Bits about anamorphic video that I believe includes some discussion of 3:2 pulldown, but the site appears to be broken right now. There's also an excellent discussion of 3:2 pulldown and the resulting potential for judder in this Secrets article . The ideal solution is to use displays that operate at 120Hz rather than 60Hz, as it allows for an easy doubling of frames to support 60fps content (video sources) as well as a quintupling of frames for 24fps content (film sources), but we are just starting to see such displays - and I don't think the Ruby is one of those.

Judder is going to be an issue whether using component or HDMI input on your Ruby - it's been an issue for many, many years now. As the Ruby is a digital display, you will be best off using the HDMI input (component will mean converting that digital video source to analog and back to digital before the LCoS can do its thing). As for which Blu-ray player, the three that I've heard the best things about are the Playstation3, Samsung's S1400, and Panasonic's BD10A. The BD10A will be joined by the BD30 later this month, and it sounds like the BD30 will match or possibly even beat the 10A for picture quality.