HDTV with 800 lines of resolution?

Archived from groups: alt.tv.tech.hdtv (More info?)

curtgottler@yahoo.com (CGott) wrote in
news:70fae150.0408311406.360e2edc@posting.google.com:

> I was looking at a Samsung hdtv recently(TXP2670WH) and I thought the
> sticker said it had 800 lines of resolution. I was under the
> impression that all hdtv's had 1080 lines of resolution, or am I
> wrong?
> This tv was a crt direct view.

A lot of smaller direct view TV sets have considerably less than the 1920
pixels of HORIZONTAL resolution. Many of them can only do about 800.
That's still more than twice what a standard NTSC analog broadcast can
achieve and a hair bit more than you'll get out of a DVD. Most Trinitron
type picture tubes do a pretty good job on the vertical resolution,
though, giving all or most of the 1080 lines. To put things in
perspective, few LCD TV's can do more than about 1440 horizontal and most
are not that good.

The limiting factor is usually the dot pitch of the screen. My computer
monitor is much better for that than my TV set is.

Some of the projection models do a fair job and the Samsung DLP 61" that
I saw in the store yesterday had a VERY fine dot pitch. Not as fine as
my computer monitor, but who is going to watch a 61" TV from 24 inches
away?

--
Dave Oldridge+
ICQ 1800667

A false witness is worse than no witness at all.

Archived from groups: alt.tv.tech.hdtv (More info?)

In article <Xns95569D6095247doldridgsprintca@24.71.223.159>,
Dave Oldridge <doldridg@leavethisoutshaw.ca> writes:
> curtgottler@yahoo.com (CGott) wrote in
> news:70fae150.0408311406.360e2edc@posting.google.com:
>
>> I was looking at a Samsung hdtv recently(TXP2670WH) and I thought the
>> sticker said it had 800 lines of resolution. I was under the
>> impression that all hdtv's had 1080 lines of resolution, or am I
>> wrong?
>> This tv was a crt direct view.
>
> A lot of smaller direct view TV sets have considerably less than the 1920
> pixels of HORIZONTAL resolution. Many of them can only do about 800.
>
Horizontal resolution is still measured as normalized to a circle, so
if the 16x9 HDTV format can THEORETICALLY resolve 1920H pixels, then
it can resolve 1920H * (9 / 16) TVL or 1080TVL. If a TV set can
resolve about 1200H pixels (within a reasonable capability for a good
CRT), then the resolution will be 675TVL.

>
> That's still more than twice what a standard NTSC analog broadcast can
> achieve and a hair bit more than you'll get out of a DVD.
>
A 16x9 DVD can likely give you a maximum (in TVL) of 720H pixels * (9 / 16) TVL
or 405TVL. The HDTV will be significantly better than DVD because of
better horizontal resolution, but also significantly better vertical
resolution.

>
> The limiting factor is usually the dot pitch of the screen. My computer
> monitor is much better for that than my TV set is.
>
Yes -- the design tradeoffs for a computer CRT are slightly different than
a consumer TV set. I still believe that consumer TV sets should be made
better than they are. I suspect that the size scaling constraints are
the biggest reason why consumer CRT TVs are so limited.

John