HD Explained

Pity the section on progressive scanning is not quite correct!

In progressive scanning each line is displayed sequentially instead of in alternate order as interlaced scanning provides. Thus interlacing is not involved in progressive scanning.

Whoops! Just noticed that it was in the 1080i description, so it is interlaced... If technical people get confused, what chance for the salesman? :)

Roll on 1080p then I'll buy HD otherwise there is no point.
 
Last edited:
JimM said:
Pity the section on progressive scanning is not quite correct!

In progressive scanning each line is displayed sequentially instead of in alternate order as interlaced scanning provides. Thus interlacing is not involved in progressive scanning.

Whoops! Just noticed that it was in the 1080i description, so it is interlaced... If technical people get confused, what chance for the salesman? :)

Roll on 1080p then I'll buy HD otherwise there is no point.
Click to expand...

Whats the point? By the time 1080p becomes the only one available, 2100p (just pulled a figure out of thin air) will be the "new" 1080. Buy 720 and wait until most programs require min 1080.
 
I watched a HD TV in Look & Listen Menlyn (at the Blu-Ray stand). Didn't look that impressive, sharper but not so much as I expected.
 
Broadcasts:
1080i50 is there for a reason. It's for broadcasting video that has a temporal resolution of 50Hz (that fluid "video look"). Another way it to broadcast using 720p50 (what DSTV is doing). Those are the two HD broadcasting standards; 1080i50 & 720p50. They are both more than enough for broadcasts.

Consumers:
Don't concern yourself with which format the broadcasters use. (720p or 1080i) Your HDTV will be compatible.
Look at the screen before you buy it:
Is it an HDTV?
Latest model?
Can't see lines from the distance you'll be watching? (if this bothers you)
Picture look good? (watch some DSTV-HD & Blue-ray)
Got the features you want?
Price right?
 
vodacom3g said:
There's a 4K spec being thrown around. Think Apple defined it.
Click to expand...

You give Apple too much credit. :)

Digital Cinema 2K: 2048 by 1080.

4K at 16:9 aspect is 4096x2304.
Many Hollywood films have been recorded on video this way for a number of years.
The cameras record progressive frames which allows for a filmic look of video.

6K is 6000 by 4000

Super Hi-Vision: 7680 by 4320

Red EPIC - 9334 by 7000

IMAX (film): 10000 x 7000

http://en.wikipedia.org/wiki/Image:UHDV2.svg
A nice comparison of many of these video formats. You'll see how tiny 1920by1080 really is.

So HD 1920x1080/30p is really a tiny video format in comparison :).
 
No-one mentions this, but the rule of thumb is that you need to sit within 3 screen heights to benefit from 1080i or 1080p. Otherwise no point, get 720p instead OR a bigger TV, even good quality SD signal will look good. Your own eyes can only resolve so many pixels per square inch - putting too many won't make a difference if you sit too close.

Here is a graph:
http://www.engadgethd.com/2006/12/09/1080p-charted-viewing-distance-to-screen-size/
Print it out and bring to the shop next time you want to buy a 1080p set.

The main reason behind HD is to get the same SD screen resolution but on a huge cinema like screen - ie about 4x. It's not really about seeing stubble or individual hair follicles on an extra's face.
 
Veroland said:
Still a good article though, I've always been getting confused between 1080i and 1080p
Click to expand...

Interlaced = only alternative lines of each frame, in the form of odd and even fields are shown at a time. So 1080i50 is 50 fields, each one showing half the available information per second. For North America and Japan: 1080i60.

Progressive = each frame is shown simultanously (at the same time) = full frame, 1080p25 or 1080p30. There is also a 1080p24 mode if the material is derrived from FILM and not VIDEO. Many prosumer and professional cameras (eg Panasonic Varicam) shoot at 1080p24
which allows direct transfer to film. Film Cameras (Panavision) record at 24 fps (frames per second) progressively (ie each frame is full - full photograph of the scene).

Video, as you can often see when you record on a camcorder, looks like video and not like film, because it's interlaced (and some other things too).
 
For everything but Blu-ray, 1080p is a waste. So unless you have an extra ten grand in the bank that you need to urgently get rid of, or you plan to spend a lot of time watching Blu-ray movies, 720p may offer better value.
Click to expand...

720 it is then :)
 
PeterCH said:
You give Apple too much credit. :)

Digital Cinema 2K: 2048 by 1080.

4K at 16:9 aspect is 4096x2304.
Click to expand...

No I'm taking about 4096 lines (as opposed to 720 or 1080 lines). Think HDMI 1.3 already supports 1440 lines.

As you know video is not normally spec'd in resolution (like PC monitors), only in the number of horisontal lines. From this you can deduce resolution depending on the aspect ratio of the material.
 
Last edited:
PeterCH, the graph is useful, but it needs an attention grabbing headline.

Here goes:

To get the full benefit of 1080p, if you're sitting 4 metres from the screen, the screen needs to have a 2.5m diagonal.

or

To get the full benefit of a 60 in Full HD TV, you need to be sitting 2.3 m from it.

I agree totally that screen size more relevant than resolution, hopefully your graph helps folks choose the right TV for their lounge setup.
 
Drunkard #1 said:
PeterCH, the graph is useful, but it needs an attention grabbing headline.

Here goes:

To get the full benefit of 1080p, if you're sitting 4 metres from the screen, the screen needs to have a 2.5m diagonal.

or

To get the full benefit of a 60 in Full HD TV, you need to be sitting 2.3 m from it.

I agree totally that screen size more relevant than resolution, hopefully your graph helps folks choose the right TV for their lounge setup.
Click to expand...

The rule of thumb is 3-3.5 screen heights. It works for everything. Go to a shop, measure how 'tall' the screen is and sit within 3-3.5xTHAT height.
If your living room is bigger, then you need a bigger TV set. If you're a super rich /b/tard :) with a tennis court sized living room, you're gonna need a display to match. 102 inches is the biggest available but a full HD projector (or a 4k projector) is an alternative. If you live in a tiny
bachelor's flat, you may only need a 32 inch display or even a 24 inch monitor.
 
Last edited:
vodacom3g said:
No I'm taking about 4096 lines (as opposed to 720 or 1080 lines). Think HDMI 1.3 already supports 1440 lines.

As you know video is not normally spec'd in resolution (like PC monitors), only in the number of horisontal lines. From this you can deduce resolution depending on the aspect ratio of the material.
Click to expand...

You know 1920by1080p25 is supported by component. :)

NHK however wants to start broadcasting in Super Hi-Vision, 7680 by 4320,
by 2015. Japan's had analog 1035i (1920x1035i60) for ages already, before the rest of the world thought of HD so I don't doubt they'll pull it off. They'll still keep the mosaics on the naughty bits though when it comes to pr0n. Think primarily baseball matches and J-pop Morning Daughter concerts at that huge res, I'm sure it will fly. :) The power of certain Japanese fans to want to watch their baseball and their favourite Junior-Jpop idols in super high def is unstoppable. :p
They will do it, for great justice :) !!!

I also don't doubt an abundance of such high resolution video. Only 2 years ago a full HD pro video camera would cost over $100K, Red (Red.com)
is now churning out 4K CMOS based video cameras for about $30K. Their EPIC format (9K) will be featured in an upcoming camera Red EPIC,
which will also cost below $100K. CMOS sensors are amazing.
 
Last edited:
You must log in or register to reply here.
Back
Top
Sign up to the MyBroadband newsletter
X