wfooshee
O, Woe is me!!
DLP is smooth with motion, just like CRTs were. The sets are bulkier, though, and people want flat-screens. (More probably, marketing people like selling flat-screens, because more of them go out in a shipment.) The motion artifacts with LCD screens is simply because LCDs can't change fast enough. They physically lag behind the picture, some much worse than others. Plasma gives you flat and responsive, both.
For the 1080p vs 1080i question: There are NO broadcasts in 1080p. Only attached devices (BluRay player, game consoles, etc.) can do 1080p. I present the following analysis:
A 720 picture has a resolution of 1280x720, or about 1 megapixel, give or take. The bandwidth allocated to digital channels allows them to refresh that megapixel 60 times a second. It draws the entire picture every 60th of a second in a single progressive scan, giving you the p in 720p.
A 1080 picture has a resolution of 1920x1080, or about 2 megapixels, give or take. That's too much information to refresh 60 times a second in the allocated bandwidth, so they break it into halves. You spend a 60th of a second doing the odd lines, then then next 60th doing the evens, back and forth. That's interlacing, giving you the i in 1080i. You get about the same amount of data flowing, about a megapixel image every 60th of a second, but it takes two scans to draw the whole picture, for an actual frame rate of 30 frames per second.
Attached devices do not have to conform to the broadcast bandwith limitation, so going to 2 megapixels every 60th of a second is no big deal, making the p in 1080p possible.
Most of the modern sets will buffer their 1080i and present it in p mode to prevent the interlacing artifact (scan lines jumping up and down) from being visible. they assemble the full frame from the 2 fields, then present it twice in a row (to take up both 60th-of-a-second time slots) without actually interlacing.
3D puts an entirely new demand on bandwidth. There is more 3D material available on BluRay than there is on broadcast, because to broadcast 3D you have to give up resolution and frame rate. The picture has to be split in two, a left-eye picture and a right-eye picture, but both pictures have to fit in the broadcast bandwidth. ESPN 3D sends the picture full width and half height, while HBO and most others I've seen use full height and half width images. If you tune a 3D picture on a non-3D set (or before turning on the 3D mode) you see a picture that's either two picture squished to fit one above the other, or squished to fit sid-by-side. I think the choice of side-by-side or over-under depends on the original HD format, as ESPN uses 720p and HBO uses 1080i. Turning on the 3D mode combines the images correctly on the set, and synchronizes the glasses to block one eye at a time. When the left eye picture is on the screen, the right eye of the glasses is black, so the left eye sees its version of the image. Then they switch, showing the right image and blacking out the left eye. It's fast enough to be flicker-free (mostly) although you can tell that you're getting a lower frame rate.
Again, BluRay and attached devices are not limited by broadcast bandwidth and don't have to send shrunken images to be reassembled by the TV. They still give up frame rate by alternating left/righ/left/right every 60th of a second, giving you a 3D frame rate of 30 per second, but each frame is full resolution rather than having to be stretched back into place.
Here endeth the lesson.
For the 1080p vs 1080i question: There are NO broadcasts in 1080p. Only attached devices (BluRay player, game consoles, etc.) can do 1080p. I present the following analysis:
A 720 picture has a resolution of 1280x720, or about 1 megapixel, give or take. The bandwidth allocated to digital channels allows them to refresh that megapixel 60 times a second. It draws the entire picture every 60th of a second in a single progressive scan, giving you the p in 720p.
A 1080 picture has a resolution of 1920x1080, or about 2 megapixels, give or take. That's too much information to refresh 60 times a second in the allocated bandwidth, so they break it into halves. You spend a 60th of a second doing the odd lines, then then next 60th doing the evens, back and forth. That's interlacing, giving you the i in 1080i. You get about the same amount of data flowing, about a megapixel image every 60th of a second, but it takes two scans to draw the whole picture, for an actual frame rate of 30 frames per second.
Attached devices do not have to conform to the broadcast bandwith limitation, so going to 2 megapixels every 60th of a second is no big deal, making the p in 1080p possible.
Most of the modern sets will buffer their 1080i and present it in p mode to prevent the interlacing artifact (scan lines jumping up and down) from being visible. they assemble the full frame from the 2 fields, then present it twice in a row (to take up both 60th-of-a-second time slots) without actually interlacing.
3D puts an entirely new demand on bandwidth. There is more 3D material available on BluRay than there is on broadcast, because to broadcast 3D you have to give up resolution and frame rate. The picture has to be split in two, a left-eye picture and a right-eye picture, but both pictures have to fit in the broadcast bandwidth. ESPN 3D sends the picture full width and half height, while HBO and most others I've seen use full height and half width images. If you tune a 3D picture on a non-3D set (or before turning on the 3D mode) you see a picture that's either two picture squished to fit one above the other, or squished to fit sid-by-side. I think the choice of side-by-side or over-under depends on the original HD format, as ESPN uses 720p and HBO uses 1080i. Turning on the 3D mode combines the images correctly on the set, and synchronizes the glasses to block one eye at a time. When the left eye picture is on the screen, the right eye of the glasses is black, so the left eye sees its version of the image. Then they switch, showing the right image and blacking out the left eye. It's fast enough to be flicker-free (mostly) although you can tell that you're getting a lower frame rate.
Again, BluRay and attached devices are not limited by broadcast bandwidth and don't have to send shrunken images to be reassembled by the TV. They still give up frame rate by alternating left/righ/left/right every 60th of a second, giving you a 3D frame rate of 30 per second, but each frame is full resolution rather than having to be stretched back into place.
Here endeth the lesson.
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So much to consider. I read 'em all and was reaching for my wallet :lol: -- then along came Aasland and Cibrd0wn with the voices of reason ! I DID recently replace the lamp in the set .. then purchased another (expensive little buggers) as a back-up. So that fact is at the back of my mind also. Consensus is I should go HD anyway, and you're all correct 
