Only CRT displays can do interlaced video. LCD and Plasma displays can not show interlaced video. They de-interlace 1080i signals. That is why they have artifacts and do not look as good as 720p or 1080p for sports or video games.
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720p or 1080i
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GreatDrok
macrumors 6502a
I've been using progressive displays for quite some time now and watching the improvements in scaling technology has been very interesting. By far the biggest problem is switching 50Hz to 60Hz and vice versa especially when dealing with interlaced video. There are very good standards converters which can take a 60Hz/525 line NTSC signal and convert it into an almost perfect 50Hz/625 line PAL signal without any visible artefacts. Formula One coverage is especially good to see this as the Canadian, American and Japanese Grands Prix are all shot in NTSC and used to look terrible when converted to PAL. These days it is difficult to see any difference. So, high end technology to do motion adaptive deinterlacing and scaling have been around for a while and this has trickled down into stuff you can buy.
A few years back, plasma and LCD screens looked rotten when showing interlaced PAL or NTSC material. You would get double images on fast motion as the two fields of the interlaced video were temporally separated by a 50th or 60th of a second so objects in fast motion would appear twice on a progressive display. However, Faroudja produced a cheap chipset called DDi which included motion adaptive deinterlacing and scaling and made all the difference in the world. It was so cheap it could go in budget displays and essentially rids us of deinterlacing artefacts. Sometimes you will see a flicker on camera angle changes for sports coverage but by and large it does a great job and even extracts the original 24fps from 3:2 pulldown 60Hz material such as my old LaserDiscs.
Basically what I am saying is that these days you can pretty much forget about having to have a panel that fits the exact resolution of the source material. Deinterlacing of 1080i material is perfect if it was originally sourced from progressive material so both fields are from the same original field and motion adaptive deinterlacing can capture fast motion and prevent double images even if the original material was shot as interlaced. Even a 1080p panel will have to deinterlace 1080i material so it isn't guaranteed that 1080p panels will handle 1080i any better than a lower resolution screen since the deinterlacing needs to happen before any scaling. Sure, if the deinterlacer does its job right there is no scaling of a 1080 signal for the panel, but for every other signal there will be upscaling and so 720 may not look as good on a 1080 screen as it does on a 720 screen but the scalers are also very good these days so you are really unlikely to notice any softness unless you are driving the screen from a computer and not matching the resolution. For video I wouldn't worry so much.
Every LCD panel out there that runs at 1366x768 or those cheap plasmas running at 1024x768 are doing some scaling of all the signals that come in and the issue isn't just the quality of the screen, but the quality of the scaler. Not all scalers are equal though and the specs on the screen won't necessarily tell you what is going to give you the picture with the fewest scaling artefacts.
Macky-Mac
macrumors 601
I don't watch much tv at all, indeed the only tv I have is an old 19" tube tv that's starting to fail. So some time in the next few months I'm going to replace it. I've got cable, but not digital cable........am I going to have to upgrade the cable to digital to use an LCD tv?
motulist
macrumors 601
Maybe I'm in the minority, but I'm fully happy with the beautiful 32" standard def tv that I got for free when someone I knew moved out of state. I see little reason to spend my disposable income on a new hd TV that's only slightly better than the great standard def crt TVs that people are just giving away these days.
I guess I'm just not a big consumer. I buy a new (or used) computer once every 5 years.
I guess I'm just not a big consumer. I buy a new (or used) computer once every 5 years.
I also see no real reason yet to upgrade. I have a 1998 Hitachi Ultravision 50" set that is going strong, although it is an analog 4:3 projection crt. I also watch very little tv, and usually watch older 30's-40's film noir movies that themselves are in 4:3 format, so why should I change to a 16:9 tv that would give me a smaller 4:3 image in a larger space (50" 4:3 vs. 50" 16:9)? To get the same 4:3 image size would require a 61" 16:9 that would be almost 2 feet wider (and I simply don't have that kind of space)! The new sets are tempting technologically, but every time I think about it I end up with the realization that I would be getting less of what I need in trade for a wider cabinet and mucho dinero.
sk8ordie
macrumors regular
Im also in no rush to upgrade, Im still on a ~ 11-12 year old 32" Sony Trinitron tube. It works great for my needs.
Once the HDDVD/BluRay war is finished I will probably pick up a new TV and DVD player...but that wont be for a while.
i am planing on buying a new HD tv... i want to know if there is a big difference between 720p and 1080i.... all the advice would be apreciated
Thanks In Advance
Well, for one thing I doubt you'll find a 1080i tv. They would be 1080p.
As for which to buy, it depends on your viewing distance and the size of the screen. In a typical living room, you sit about 15-20 feet away from the screen. At that distance, if you get a 60" or bigger, then go ahead and get 1080. Otherwise, you won't be able to see the difference between 720 and 1080. For example, a 42" tv. Which, by the way, is way too small for that size room anyway.
At a distance of 15-20 feet, your going to want a 50" tv minimum.
GreatDrok
macrumors 6502a
I'm struggling to see the point of 1080p at the moment given the price premium. I'm currently watching a 720p DLP projector running at 120" and there is no pixel structure visible from my normal viewing distance of 12 feet. Based on this you would have to go bigger still to get any benefit from 1080p, probably pushing 200".
Well, having gone from a 50" 720p to a 60" 1080p and sitting about 15' away, I can see the difference. Having said that, it isn't terribly dramatic. Just more detailed. Nothing like going from 320 to 720.
And it's hard to discern how much improvement is due to the resolution. My new tv is better in every way, color, blacks, contrast, everything.
Also, there is a big difference if your talking about games, like on ps3.
I can't imagine that you wouldn't see a difference. Especially at that size and distance.
Well, for one thing, unless you're making calibration adjustments, your tv probably has some bad convergence issues at this point. Also, if your watching black and white, a plasma is going to do a lot better at actual black and white (as opposed to black and white with some coloring). And you do realize that a new hdtv will take up FAR less actual space than what you have now, right?
ugh, I could never watch a tv that small, well unless I was sitting about 2 feet away. Forget about resolution, just watching a dvd in the original aspect ratio is painful. A postage stamp picture...
motulist
macrumors 601
I don't see the fascination with sitting so close to a screen. I was at Best Buy the other day and they had a chart of "optimum" seating distances for various sizes of tv displays. I laughed when I saw the "optimum" distance for a 65" hdtv was 6 feet, and 4 feet for a 50"! I sit about 12 feet from my 50" and that seems about right to me. Moving up to 4 feet away I would have to move my head to see the whole screen! I guess they are trying to get you close enough that you can tell the difference between 720p and 1080p, but I think sitting that close is unrealistic.
It's utter nonsense designed to sell progressively larger televisions. People sat a dozen feet away from 15" televisions for decades, and didn't think twice of it. In today's era of "large" TVs though, the goal is to sell the largest televisions possible, which is why retailers are preoccupied with calculating "optimum" distances for you, and telling you how you need a $1000 television if you plan to watch it from your couch after work.
Actually, there's some accuracy to the optimum distance calculation (although it will vary by person).
The previous generation TV and it's TV signal would not allow you to sit close without seen the grains and artifacts until High Definition came along (unless you have 15" CRT as noted above).
I've have many friends who wished they've got larger TV. I have yet to meet anyone who complained that their TV is too big.
You should look at multiple TV's at the store to see if 1080p will make difference to you.
For me 58" Panasonic Plasma at 14ft didn't make a difference so I went with 768P. The price difference were $1,900 (yes, 1080P was double the 768p cost).
I'm still very happy after 1 month of extensive usage 🙂
Stridder44
macrumors 68040
What he said. I got a Philips plasma about 3 years ago that does up to 1080i (ever since then I've been trying to find whether 1080i or 720p looks better). But nowadays, it would be stupid to cheat yourself out and not get a tv that does 1080p.
Like he said, go for 1080p, providing you've got a decent amount of space between you and the tv. It will be worth it in the long run. 50" is a nice figure to go with too by the way.
While the optimum distance stated seems a little silly, the distances that most people use have been set mostly by THX, the theater sound people.
And guess what, it isn't utter nonsense. There is hard science behind it, based on what the human eye can actually perceive in resolution.
And the simple difference between your 15" tube set and a current set is that the resolution on that old set was pathetic. At best, it was 400 lines or so of resolution displaying a 320x240 image.
The reality is that people tend to sit closer when watching a hdtv broadcast. And they do it unconsciously. And they haven't been told to do so by Best Buy. When HDTV sets first came out they recommended the same distances as with a regular set. However, they realized that people moved closer to the set, so they adjusted the recommended distances. It has to do with the clarity of the picture.
Your more than welcome to buy a 15" lcd and sit 30' away. It just will be a bad viewing experience. Or of course you can wait 10 years and buy a 50" set for $300. Or, just read a book.
Not at all. I had an old 32" sony wega trinitron tv in my bedroom. I could never go back to watching it. I'd put on a dvd in widescreen and get a 20" picture. 40% of the screen was black. It looked nice, just in miniature. Besides, a new tv is going to have 2-3 times the resolution of that tv.
It's the difference between a 320x240 jpeg or a 1920x1080 jpeg. Which is going to look better?
Just because you can watch a dvd on a 32" tv doesn't mean its good. You could also just watch it in tinny stereo, or even mono, but I also happen to prefer surround sound through non-junk speakers.
But hey, whatever. A lot of people buy Camrys. And they will get from a to b. Doesn't mean it's a good driving experience.
Well, you might not currently see pixel structure, but that isn't the point. The point with recommended viewing distances is the point at which the benefits of the higher resolution become visibly noticeable. Basically, at your viewing distance, you'd see the difference in resolution. The picture will be noticeably sharper. Whether or not that is worth upgrading to 1080p is up to you.
Since a lot of people seem confused about this, here is a link:
http://www.carltonbale.com/2006/11/1080p-does-matter/
