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"Digital" is a buzzword today, and it is regularly abused. Most "digital" cable is NOT transferring high definition digital signals, but they are transferring the 480i NTSC analog signals into digital format, so that they can compress them, to get more channels across the line. So being digital, does not always mean better quality.
People are looking for Digital TVs, and now looking especially for ones with DVI inputs, and although a full digital-to-digital transmission and playback will be cool, the analog to digital translation is VERY good at HDTV resolutions.
A MUCH more important variable is the actual resolution that you are viewing on the TV.
Also mostly all consumer display devices cannot actually resolve the full 1920 X 1080i resolution. But the consumer electronics companies conveniently don't measure the display's resolvable resolution, but the maximum digital input resolution (often called the addressable resolution), which is the highest resolution signal that the internal scaler can sync to.
Some digital displays are actually digital in their technology (like plasma, LCD, DLP, D-ILA/LCOS/SXRD) as opposed to CRT-based displays (tube TVs, most RPTVs, and CRT-FPTVs) that use analog CRTs.
True digital technology displays have a "native" resolution, which is the maximum (and only) resolution that they are going to display. So if you input NTSC 480i broadcast TV, the internal scaler will convert the analog signal into digital and then upconvert the 480p image to match the digital display's native resolution. Say 1280 X 720p, with gray bars formatting the 4 by 3 active image to around 1024 X 720p.
And likewise when a higher resolution image like 1920 X 1080i is recieved, the display's internal scaler downconverts and deinterlaces the image to the display's 1280 X 720p native resolution.
But even if the source signal is digital (HDTV), the connection to the TV is almost always analog (progressive component or RGB), which is internally converted back to digital, for digital technology displays.
And the difference with CRT-based displays (Tube TVs, RPTVs and FPTVs) is that the scaler will take in the signal and if it not within the CRT's frequency range, it will downconvert it, and if it IS within the TV's scan capabilities, the display will do it's best to resolve the image.
But NTSC-only TVs will only show a 640 X 480i image (regardless of 1000 lines of resolution claims) most digital capable tube TVs max out around 900 X 750i resolvable resolution, with RPTVs around 1150 X 800i, and better CRT FPTVs capable of around 1280 X 1024 resolvable resolution.
The biggest reason for converting to digital connectivity is NOT for enhanced picture clarity, but to introduce digital copy protection into the TV to prevent media piracy, and content copy theft. DVI is the front contender with their HDCP/HDMI encryption, but it is NOT the standard, with 5C/Firewire and DFAST competing standards out there.
Generally, if your TV doesn't have a HDTV input (Y-PbPr, RGB, DVI) then like most TVs it's a 480i analog-only TV. But if it can accept a progressive input from a progressive-scan DVD player (not analog component, S-Video, or composite) then it can also accept and display a HDTV signal as well. Even though it's not fully resolving the 1920 X 1080 resolution.
And before you start regretting that current digital-capable "HDTV" diplays cannot full resolve HDTV, understand that depending on the size of the display, and the distance that you are viewing it from, your eyes might be the weak link in this chain. With most people needing to be only one screen-width away from the display to be able to fully discern 1920 X 1080i resolution.
And it's quite likely that 1280 X 720p will look just as good from 20' away from a 96" widescreen image showing HDTV material as full 1080i.
-Dean.
People are looking for Digital TVs, and now looking especially for ones with DVI inputs, and although a full digital-to-digital transmission and playback will be cool, the analog to digital translation is VERY good at HDTV resolutions.
A MUCH more important variable is the actual resolution that you are viewing on the TV.
Also mostly all consumer display devices cannot actually resolve the full 1920 X 1080i resolution. But the consumer electronics companies conveniently don't measure the display's resolvable resolution, but the maximum digital input resolution (often called the addressable resolution), which is the highest resolution signal that the internal scaler can sync to.
Some digital displays are actually digital in their technology (like plasma, LCD, DLP, D-ILA/LCOS/SXRD) as opposed to CRT-based displays (tube TVs, most RPTVs, and CRT-FPTVs) that use analog CRTs.
True digital technology displays have a "native" resolution, which is the maximum (and only) resolution that they are going to display. So if you input NTSC 480i broadcast TV, the internal scaler will convert the analog signal into digital and then upconvert the 480p image to match the digital display's native resolution. Say 1280 X 720p, with gray bars formatting the 4 by 3 active image to around 1024 X 720p.
And likewise when a higher resolution image like 1920 X 1080i is recieved, the display's internal scaler downconverts and deinterlaces the image to the display's 1280 X 720p native resolution.
But even if the source signal is digital (HDTV), the connection to the TV is almost always analog (progressive component or RGB), which is internally converted back to digital, for digital technology displays.
And the difference with CRT-based displays (Tube TVs, RPTVs and FPTVs) is that the scaler will take in the signal and if it not within the CRT's frequency range, it will downconvert it, and if it IS within the TV's scan capabilities, the display will do it's best to resolve the image.
But NTSC-only TVs will only show a 640 X 480i image (regardless of 1000 lines of resolution claims) most digital capable tube TVs max out around 900 X 750i resolvable resolution, with RPTVs around 1150 X 800i, and better CRT FPTVs capable of around 1280 X 1024 resolvable resolution.
The biggest reason for converting to digital connectivity is NOT for enhanced picture clarity, but to introduce digital copy protection into the TV to prevent media piracy, and content copy theft. DVI is the front contender with their HDCP/HDMI encryption, but it is NOT the standard, with 5C/Firewire and DFAST competing standards out there.
Generally, if your TV doesn't have a HDTV input (Y-PbPr, RGB, DVI) then like most TVs it's a 480i analog-only TV. But if it can accept a progressive input from a progressive-scan DVD player (not analog component, S-Video, or composite) then it can also accept and display a HDTV signal as well. Even though it's not fully resolving the 1920 X 1080 resolution.
And before you start regretting that current digital-capable "HDTV" diplays cannot full resolve HDTV, understand that depending on the size of the display, and the distance that you are viewing it from, your eyes might be the weak link in this chain. With most people needing to be only one screen-width away from the display to be able to fully discern 1920 X 1080i resolution.
And it's quite likely that 1280 X 720p will look just as good from 20' away from a 96" widescreen image showing HDTV material as full 1080i.
-Dean.
Luke: "Hey, I'm not such a bad pilot myself, you know"
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