View Full Version : A little confused?


tazpc
01-05-07, 04:21 AM
A little advice would be appreciated. i am intereseted in going Hi-def.
Currently have a HS50 from Sony. Which is a native 1280 720 PJ. It says it can accept 1080/24PsF What is this and is it better than the 1080/50i signal that I am currently feeding it. Confused ???

Thanks Tariq

marcusm750
01-05-07, 09:37 AM
If you're projector can do 1080p/24fps (frames per second), then frame rate conversions can be skipped when sourced by either HD DVD or BD playing material encoded as such (native frame rate for film is 24fps). The advantage is not spatial (ie. resolution, geometry, etc. of the image you see), but rather temporal (how the individual frames are displayed to make motion possible). With a 1080i/50 signal, a conversion must be done to go from 24 progressive frames to 50 interlaced fields (25 frames) which adds lots of "time distortions" expressed as blurry movements, judder, and other artifacts.

In other words, you're getting "mechanically" closer to how the film is shot and presented in a theater: at its native frame rate and in high-definition resolution. To quote that hag Martha, "it's a good thing!" :)

tazpc
01-05-07, 10:42 AM
Thanks Marcus, in the Manual it is very specific about the PsF and not FPS.
I read it to mean a 1080p image at a rate of 24 but the PJ is only a 720p. What on earth will I be viewing ?

fa8362
01-05-07, 11:07 AM
Thanks Marcus, in the Manual it is very specific about the PsF and not FPS.
I read it to mean a 1080p image at a rate of 24 but the PJ is only a 720p. What on earth will I be viewing ?

Your projector will downconvert the image to its native resolution. You won't see a 1080p image, instead, you'll see a downconverted image.

marcusm750
01-05-07, 12:15 PM
Your projector will downconvert the image to its native resolution. You won't see a 1080p image, instead, you'll see a downconverted image.
Correct. The resolution will be scaled down to 720, but that does not affect the 24fps capability. Skipping the frame rate conversions, even at lower resolutions (compared to the 1080p on the disc), is a big improvement.

marcusm750
01-05-07, 12:26 PM
Thanks Marcus, in the Manual it is very specific about the PsF and not FPS.
Hmm, don't know what "PsF" could mean. Typically the "p" goes with the resolution to indicate if it's progressive or interlaced (ie. 1080p, 1080i, etc.). The units for the frame (or refresh) rate are implied, but technically they are: frames per second (fps) for 24, and Hertz (Hz) for 50 or 60. Some label all three values as Hz which is OK too but a little less accurate.

I read it to mean a 1080p image at a rate of 24...
Exactly correct.

cadillacjr
01-05-07, 12:39 PM
24 PsF stands for 24 Progressive segmented Frame. It is 24 frames per second but
each frame is split into 2 halves. To me it sounds like interlaced but, according to people who understand it better than me, it's different.

It was popular a couple of years ago. When the Sony Qualia projector came out this was the only type of 1080 signal it could accept.
You don't seem to hear about it much anymore.

marcusm750
01-05-07, 01:15 PM
24 PsF stands for 24 Progressive segmented Frame. It is 24 frames per second but each frame is split into 2 halves. To me it sounds like interlaced but, according to people who understand it better than me, it's different. It was popular a couple of years ago. When the Sony Qualia projector came out this was the only type of 1080 signal it could accept. You don't seem to hear about it much anymore.
Cool! Thanks for the info. I'm guessing that due to the "segmenting" it is not compatible with the 24fps signal from either HD DVD or BD? I'll do some research and will report.