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Resolution question

jkkyler
09-07-2009, 04:39 PM
Is scaling (upconverting/downconverting) happen independent of frame rate. Meaning, can I downconvert from 1080p/24 to 720p and keep it at 24fps or will it gp to 720p/60. The reason I ask is that my projector PT-AX200u is 720p but accepts a 1080p/24 signal and runs at 24fps effectively giving 720p/24.

Currently 480p,720p,1080i and 1080p 24/60 are all fed to my projector natively as my Sat/HDDVR is set to native and my AVR to passthrough since two different displays are plugged/unplugged as needed. My tv does an acceptable/good job of upscaling 480 content but my projector not so much. I plan on adding an Onkyo TX-NR 905 w/ dual HDMI Outputs and trying the REON-VX HQV chip do the video processing -set to 1080p for my 1080p Plasma HDTV and set to 720p for my projector but I was wondering if when 1080p/24 was downconverted would it still be passed on as 720p/24 and does the PT-AX200u accept a 720p/24 signal. I don't know if their exists a 720p/24 spec.

Lee Stewart
09-07-2009, 05:11 PM
Is scaling (upconverting/downconverting) happen independent of frame rate. Meaning, can I downconvert from 1080p/24 to 720p and keep it at 24fps or will it gp to 720p/60. The reason I ask is that my projector PT-AX200u is 720p but accepts a 1080p/24 signal and runs at 24fps effectively giving 720p/24.

Currently 480p,720p,1080i and 1080p 24/60 are all fed to my projector natively as my Sat/HDDVR is set to native and my AVR to passthrough since two different displays are plugged/unplugged as needed. My tv does an acceptable/good job of upscaling 480 content but my projector not so much. I plan on adding an Onkyo TX-NR 905 w/ dual HDMI Outputs and trying the REON-VX HQV chip do the video processing -set to 1080p for my 1080p Plasma HDTV and set to 720p for my projector but I was wondering if when 1080p/24 was downconverted would it still be passed on as 720p/24 and does the PT-AX200u accept a 720p/24 signal. I don't know if their exists a 720p/24 spec.

Frame rate is independent of resolution

Your projector can handle 24P properly because it has a vertical scan rate of:

Vertical scanning frequency 50 Hz - 87 Hz (page 48 owners manual)

So you should have an option to run 24P from bluray at 72 hz which is the same frame rate that Pioneer used for it's plasma HDTV's.

The down conversion from 1080x24P will result in 720x24P which your PJ will multiple 3X to get rid of frame judder by having no 3:2 pulldown.

The benefit of 1080p/24 transmission between the HD player and the projector is that it eliminates the need for 24 frame/sec film material to go through 2:3 pulldown conversion. This conversion has always been necessary to get film to synch with the 60 cycle displays that are part of the NTSC world. But with digital projectors being able to run at 24 Hz (or multiples thereof, 48 or 72 Hz), the conversion to 60 Hz is no longer needed. This will reduce occasional artifacts such as judder in slow panning sequences and allow a smoother, cleaner display of the film source.

http://www.projectorcentral.com/panasonic_ax200u_home_theater_projector.htm