Originally posted by: Fox5
Originally posted by: rbV5
CRTs have the same problem in the end. The electron beam can't do both progressive and interlaced material natively.
My 22" CRT certainly can (its something you can test for yourself), interlaced resolutions aren't pretty, but they are supported with my Radeon card...how do explain that?
The CRT doesn't natively support anything interlaced, it's the drivers of the Radeon that can buffer the image.
Checking the specs on a newer model(mine is likely a bit lower, but similar) It states specs 30 kHz to 140 kHz for hrizontal scan rates and vertical refresh 50 Hz to 160 Hz. I don't think any CRT cares whether the signal is interlaced or progressive, it just displays an image (auto sync's) if it supports the horizontal scan rate at a supported refresh rate. The radeon card itself with Catalyst Drivers does have interlaced output support. I could be just misunderstanding it, or mis-stating it slightly as far as how a CRT monitor displays the interlaced signal itself, but my understanding is that each field is displayed at the vertical refresh of 60Hz to produce the 30 FPS framerate of 1080i (1080p has a framerate of 30FPs and 24FPS not 60FPS btw, 720p can be 24,30 or 60 FPS)
The signal my CRT monitor receives for 1920x1080@30Hz interlaced and 1920x1080@60Hz driver settings are definately different (and definately display much differently),
Using my CRT monitor's OSD Diagnosis utility (horizontal scan rate/refresh rate)
1920x1080@30Hz interlaced reports as 33 kHz @ 59Hz (not pretty)
1920x1080@60Hz reports as 67kHz @ 59Hz (flicker, but due to the refresh rate)
1280x720@60Hz reports as 44kHz@ 59Hz (as above)
At 60Hz vertical refresh, my understanding is:
480p and 960i is 31.5 Khz horizontal scanrate
540p and 1080i is 33.75 Khz horizontal scanrate
720p and 1440i is 45 Khz horizontal scanrate
So, I'm not really certain that it is truely interlaced (I'm just a PC enthusiast, and many of the finer details concerning video continue to confuse me), but I'm just guessing that my RPTV supports a much narrower horizontal scanrate at 60Hz than my CRT (31.5 and 33.75 for 480p and 1080i, the resolutions it supports natively) I really doubt it supports to 67kHz, and the reported scanrate from my monitor corresponds to the known 1080i specs.