I've been hearing lately that sending 48Hz to the projector gives a more "film-like" experience. The only source I use (or need) is an HTPC running Debian to HDMI, and Xwindows can only put out a fixed refresh, so I must choose 48 or 60. (or higher?) 90% of my viewing is recorded DishNetwork HD and OTA HD, each at 59.970 Hz natively, and H.264 and mpeg2.

Are they saying it's more film-like because there's flicker? If so, no thanks. Or is there a qualitative difference?

What gives?

It's all about the source framerate and how it's displayed. Most movies are 24 fps, and that can't be evenly put into 60Hz refresh. If you feed the projector 60Hz, then every other frame is refreshed a different number of times, 3 times, then 2, 3, 2. This creates judder, or unsmoothness in the display of the movie that's not in the source.

Feeding the projector 24, or 48Hz, eliminates the uneven refresh judder. Ideally you change your refresh rate based on content.

But if you must choose, you don't want to use 48Hz, 60fps/Hz content will look absolutely horrible if displayed at 48Hz.

Thanks. The vast majority of my source material is at 59.970Hz, so it sounds like that's what I should set X to.

Yeah, ideally you want to switch, if that's not an option (can you setup a shortcut to switch or something?) then you definitely want to use 60Hz..

I could have it change on the fly, but I question the value of it. For the 10% of the time I watch a BluRay, would it be worth it to switch to 48Hz?

Only way to know is to try it and see if it's worth it to you.

I've been hearing lately that sending 48Hz to the projector gives a more "film-like" experience. The only source I use (or need) is an HTPC running Debian to HDMI, and Xwindows can only put out a fixed refresh, so I must choose 48 or 60. (or higher?) 90% of my viewing is recorded DishNetwork HD and OTA HD, each at 59.970 Hz natively, and H.264 and mpeg2.

Are they saying it's more film-like because there's flicker? If so, no thanks. Or is there a qualitative difference?

What gives?

If the source is "film" based Blu-ray, DVD, Sat etc then it will probably have a 24fps capture rate. For NTSC 60hz these frames are simply repeated in an odd/even 3:2 sequence five times per second to get 24 frames to fit into 60(hz). The downside is the unequal 3:2 repeat causes additional judder that is most noticeable during panning. Although if you have grown up viewing film at 60hz you may be conditioned to it and don't really notice. If you haven't the judder can be very distracting compared to system that use equal frame repeat i.e. 2:2.

Thus a display that can properly process a 24hz,48hz etc input for film material should eliminate the 60hz 3:2 repeat judder. The display will simply repeat these frames in a equal 2:2,3:3,4:4 etc type fashion depending on the display tech.

D