New FAQ

[57U]

I've developed the following post which I will soon move into the FAQs. Before I do that, I wanted some feedback, suggestions. Once the feedback dies down, I'll repost a revised version in the FAQs. Thanks in advance for your comments. (I've tried to limit the advantages/disadvantages to three of each.)

Comparison of Display Types:

Each type of HDTV has advantages and disadvantages.
Here is a short list for each display type:

CRT-based RPTVs

Advantages:

Least expensive per inch (available in sizes 40" – 80")
Easily repairable
Excellent colour rendition, including blacks
"Known quantity" for many years

Disadvantages:

Requires initial and periodic convergence and setup
Large, "ugly" black box (typically) (takes up floor space)
Susceptible to burn in

There are no CRT-based RPTVs that can natively display 720P. If the TV accepts 720P it gets converted to 1080i or 480P, depending on the set.


Direct View HDTVs

Advantages:

Smaller size for some smaller rooms/entertainment centers (maximum size 40")
No need for convergence.
Better vertical viewing angle than RPTVs

Disadvantages:

If tube goes bad, repair cost is exorbitant – equivalent to cost of new TV
Horizontal resolution typically 800-1000 lines max (100-300 lines less than RPTVs)
Can burn in
Very heavy in the larger sizes.

There are no "consumer" Direct View TVs that can natively display 720P. If the TV accepts 720P it gets converted to 1080i or 480P, depending on the set.


LCD-based RPTVs

Advantages:

Light/compact for its screen size
High resolution – 720P (actually 768P) (720P is considered by many to be superior to 1080i, hence the higher price for these sets)
No need for convergence.
Less sensitive to burn in than CRTs, but still some greyscale degradation possible.

Disadvantages:

Periodic lamp replacement - about 2 years - ~$200-$400.
More expensive than CRT-based RPTV
Doesn’t display blacks well


DLP-based RPTVs

Advantages:

Light/compact for its screen size
High resolution – 720P (720P is considered by many to be superior to 1080i, hence the higher price for these sets)
No need for convergence.
No possibility of burn in

Disadvantages:

Periodic lamp replacement - about 2 years - ~$200-$400.
More expensive than CRT-based RPTV
Doesn’t display blacks well


Flat Panel LCDs

Advantages:

Sexy, thin, light, can hang on the wall
Excellent resolution (768P typical)

Disadvantages:

Extremely expensive
Only available in smaller sizes at this time
Doesn’t display blacks well

Be careful - inexpensive flat panel displays may be 480P only.



Plasma

Advantages:

Sexy, thin, can hang on the wall
Available in sizes to 61" (expensive)
Excellent resolution (768P typical)

Disadvantages:

Expensive
Does not display blacks well
Susceptible to burn in
Some have difficulty with multiple inputs

Be careful - inexpensive plasma displays may be 480P only.



Projection

Advantages:

Large, variable screen size
Compact unit
Excellent viewing angles

Disadvantages:

Typically need dedicated, darkened "home theater"
Lamp life (LCD/DLP) - about 2 years - ~$200-$400.
Be extremely careful when buying regarding resolution. 720P units are $5000+, yet some units are on the market with lower (non-HD) resolutions for $1000+…


LCoS-based RPTVs

Advantages:

High resolution – 1080P
No need for convergence.

Disadvantages:

Only a couple of manufacturers
Very expensive, new technology
Doesn’t display blacks as well as CRTs


OLED

Organic Light Emitting Diodes – possibly the future of flat panel displays
Will make inroads into PDAs, cellphones, digital cameras, etc.

Advantages:

Can be made into a flexible thin display – like plastic
Sexy

Disadvantages:

Not yet available for TVs
Largest size to date – 20", proven only in small displays – 4" or less
Concerns regarding long term viability of actual OLED system (display fades quickly)


Holodecks

In your dreams…

[mhdiab]

Under Projector:

720P units are $5000+, yet some units are on the market with lower resolutions for $1000+…

I think that most people when reading the FAQ will not realize that lower resolution means no true HD - so should probably be spelled out ...lower resolution, which is not HD, for ....

Just a thought - also great stuff really good FAQ about something that is really needed.

Also under Plasma: Very susceptible to burn in

Is this 100% correct? I was under the impression that this was fairly hard on to do on a plasma..

[57U]

Thanks for the comments. Made the change under projectors. As for Plasmas, the burn in comment stands (although softened) as they are susceptible to burn in.

[mikehbkwm]

57 nice faq I think you covered it pretty well couldnt think of anything else you could add to it.............

The holodeck thing thats funny.........

[Jester]

The same (Non-HD) applies to most Flat Panel LCDs. They usually require scaling to display an HD image. If the aspect ratio is 4:3 and the display resolution is 1024x768 or less, the output will be Non-HD. I think that the 768p specification is misleading because on a 4:3 display 768p will only be displayed when upconverting 480i or 480p and depending on the scaler this will typically soften the resulting image.

The Zenith L30W26 is a good example of a widescreen LCD that is Hi-Def. It is 30" and has a display resolution of 1280x768. This is a little confusing because a true 16:9 should be 1280x720, so you are either losing 48 pixels to black bars (let's hope they are hidden behind the bezel) or it has to rescale the vertical picture which would be obtuse because it would mess up the aspect ratio (so I doubt they do this).

Surprisingly, some widescreen LCDs are Non-HD. The Sharp Aquos LC-22SV2U has a 16:9 aspect ratio, is 22" and has a display resolution of 854x480. DOH!

[fbleahy]

57U.....you may want to mention the heavy weight of the bigger direct views. The 36" Sony's are 230 lbs!!!! That was a big turn off for me. Just a thought.

[mikehbkwm]

Yeah i remember helping my old roommate move last year and we moved his 230 pound Sony trinitron 2000 model and it SUCKED........................ But ill admit that thing will produce a pretty picture for an analog set...........

[spaceman_spiff]

Great Job 57, as always you have put great deal of effort in creating this. :)
I would also include the viewing angles. Most RPTVs (CRT, LCD, DLP etc) have relatively low vertical viewing angle, typically +/- 15-35 deg. Direct View TVs can go in the range of +/- 80.
CRT based TVs are prone to magnetic field interference and distortions.
On CRT based RPTVs, you mentioned large ugly box, I would also add 'Poor use of floor space', especially if you want bigger screen and dont have enough room.
Some RPTVs have problems of reflection which could be worse than Direct View sets.
In front projection section, in the part that you mention, 'Need a dedicated home theater', I would also add the problem of lighting conditions. Poor lighting conditions can make the experience rather unimpressive.
These are most of things that I can think of right now. :) I will keep posting when I think of anything else.

[spaceman_spiff]

Originally posted by 57U

Lamp life (LCD/DLP)
Be extremely careful when buying regarding resolution. 720P units are $5000+, yet some units are on the market with lower (non-HD) resolutions for $1000+…

[/B]

Do you want to mention prices, because as time goes by, prices will change which might make it irrelevant for the future. Just a thought.:D

[57U]

Thanks for the comments so far. I've incorporated most of them. Keep the comments coming if necessary.

[keving]

Can you expand, or possibly create another FAQ with a little more technical info describing the differences between these different types of TVs? A definition of the acronym isn't quite enough for me to understand what they are, how they differ, which may be better or a better bargain, etc.

All I know is my TV is a rear projection, and it ain't Plasma or LCD. Beyond that, I can't logically come to a conclusion as to which of the other varieties mine is.

[57U]

Most people buy CRT-based TVs. Whether they're direct view or RPTVs. These are the "least expensive"

If anyone is going to purchase an LCD-based, DLP-based, or other TV, these cost a lot more (sometimes 2-10 times as much as a similar size CRT-based RPTV) and people would do the research required.

If you don't know what yours is, it's probably CRT-based.

[HDMAN]

Good Summary 57...

Just one comment.

You refer to some advantages being higher resolution at 720p, and I know this has been debated in many posts, but the average consumer may not really know the difference between 720p and 1080i, and general interest stores like Circuit City and Best Buy talk refer to 1080i in a lot of their promotional literature, as well as advertisements. When they refer to HD capable or eady, as least for now, they are referring to 1080i and 720p, aren't they? Add the fact that ABC uses the 720p format, and the others use 1080i, it can be confusing.

But you are dead on about 480p. At the Skyforum satellite conference recently in NYC, broadcasters from CBS and NBC heard from some Fox broadcasters that Fox was rethinking their HDTV position and the use of 480p.

[rikelm]

I thought you might add to the disadvantage of a DLP base projector or RPTV that as new technology, no on is sure of the reliabilty of the micro mirrors. If a mirror burns out it leaves a permanent black spot on the screen. Mine is DLP based and I thought I had a mirror burned out and almost paniced till I found out it was dust on the lens. According to Sharp and Texas Ins. they proved to be reliable in testing but there was a very, very small failure rate. In the field they report .02% with a projected lifetime of 100,000 hours of normal use.

TI site (http://www.dlp.com/dlp_technology/dlp_technology_white_papers.asp)


I'm guessing the same problem would apply to all pixal based sets also

[mikehbkwm]

hmmmm didnt know that a mirror could go bad on a DLP based set.... That technology is getting better by the day because everytime I go to Best Buy I go take a look at the Samsungs ........ they sure are pretty :p