Where did 1280x1024 come from?

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Mxsmanic

Why is 1280x1024 so often included among other resolutions as an
option for hardware and software monitor configuration? Almost all
monitors have a 4:3 aspect ratio, and all selectable resolutions have
the same ratio ... except 1280x1024. Why this exception to the rule?
There must be some sort of historical reason for it.
 
| Why is 1280x1024 so often included among other resolutions as an
| option for hardware and software monitor configuration? Almost all
| monitors have a 4:3 aspect ratio, and all selectable resolutions have
| the same ratio ... except 1280x1024. Why this exception to the rule?
| There must be some sort of historical reason for it.

I've wondered that as well, but my questions about it have never resulted in any
logical answers. My CRT is set to 1280 x 960, which is 4:3.

Larc



§§§ - Change planet to earth to reply by email - §§§
 
Mxsmanic said:
Why is 1280x1024 so often included among other resolutions as an
option for hardware and software monitor configuration? Almost all
monitors have a 4:3 aspect ratio, and all selectable resolutions have
the same ratio ... except 1280x1024. Why this exception to the rule?
There must be some sort of historical reason for it.
Click to expand...

Wish I could tell ya but I don't know either.

That's the resolution I'm using, though,
 
Lez Pawl said:
same here and its perfect for my 19"er
Click to expand...

From elsewhere in cyberland:

"For mostly obscure hardware reasons, early DRAM/VRAM
graphics controller implementations favored horizontal
resolutions that were a multiple of the row size. 1280 is
divisible by 256, the row size of a 64K DRAM.

One of those obscure reasons was address translation. If you
form the linear framebuffer address as (2048*y)+x, it made
doing blt hardware much easier: just map x and y onto the
appropriate row and column bits.

Another of those reasons was being able to load the video
shift registers at the same times each line. This made the timing
control easier to do in the logic of the day (think MSI counters
and gates.)

Modern gfx conrollers refresh the display using periodic burst
DRAM access instead of actual shift registers; and they have
hardware to help deal with the x-y to linear address translation.
So the whole issue of row size pretty much goes away."
 
EDM said:
From elsewhere in cyberland:

"For mostly obscure hardware reasons, early DRAM/VRAM
graphics controller implementations favored horizontal
resolutions that were a multiple of the row size. 1280 is
divisible by 256, the row size of a 64K DRAM.

One of those obscure reasons was address translation. If you
form the linear framebuffer address as (2048*y)+x, it made
doing blt hardware much easier: just map x and y onto the
appropriate row and column bits.

Another of those reasons was being able to load the video
shift registers at the same times each line. This made the timing
control easier to do in the logic of the day (think MSI counters
and gates.)

Modern gfx conrollers refresh the display using periodic burst
DRAM access instead of actual shift registers; and they have
hardware to help deal with the x-y to linear address translation.
So the whole issue of row size pretty much goes away."
Click to expand...

do you know, I was just gonna say that.
 
Mxsmanic said:
Why is 1280x1024 so often included among other resolutions as an
option for hardware and software monitor configuration? Almost all
monitors have a 4:3 aspect ratio, and all selectable resolutions have
the same ratio ... except 1280x1024. Why this exception to the rule?
There must be some sort of historical reason for it.
Click to expand...
All standard LCD monitors are 5:4 ratio, the only ones that are not are
widescreen models. 17" and 19" LCD's have a native resolution of
1280x1024, these are the most bought monitors now. That means most
monitors have a 5:4 aspect ratio and not 4:3 as you said. Very few
people buy 4:3 crt's anymore.
 
Garrot rattled this off his keyboard on 8/21/2006 :
All standard LCD monitors are 5:4 ratio, the only ones that are not are
widescreen models. 17" and 19" LCD's have a native resolution of 1280x1024,
these are the most bought monitors now. That means most monitors have a 5:4
aspect ratio and not 4:3 as you said. Very few people buy 4:3 crt's anymore.
Click to expand...

Bingo, give the man an Havana.
 
Except the 1280x1024 resolution pre-dated the commonly available LCD panels.

Take back the man's cigar...

Clint
 
Clint rattled this off his keyboard on 8/21/2006 :
Except the 1280x1024 resolution pre-dated the commonly available LCD panels.

Take back the man's cigar...
Click to expand...

<snip>

The only time you should use 1280x1024 is if it is the native
resolution of an LCD monitor. If you are using a CRT monitor, do not
use 1280x1024. Why?

Monitors have something called an aspect ratio. This is the ratio
between the horizontal and vertical dimensions of the monitor, and
determines whether the monitor is more square-shaped or more
rectangular. Virtually all CRT monitors and many LCD monitors have a
4:3 aspect ratio, which means if you divide the horizontal size by the
vertical size, you will get (roughly) 4/3, or 1.333333333… repeating.

Screen resolutions also have their own aspect ratio, which is
independent of the aspect ratio of the monitor. Fortunately, most
popular resolutions (800x600, 1024x768, 1152x864, 1600x1200, etc.) are
also a 4:3 aspect ratio, so when you display them on a 4:3 monitor,
everything looks normal. Here is the problem: 1280x1024 is not a 4:3
resolution. It is, in fact, 5:4. Thus, if you use 1280x1024 on a
normal 4:3 ratio monitor (most CRTs are 4:3), everything will be
squished vertically because the aspect ratios are different. There is
no way around this; if your monitor is 4:3, the resolution you want is
1280x960, not 1280x1024.

Of course, it’s more complicated than this. Many new LCD monitors have
a native resolution of 1280x1024. This means that the monitor itself
is now a 5:4 ratio, so regular resolutions will be wrong. 800x600,
1024x768, 1152x864, 1600x1200, none of these will display properly.
Confusing things even more, there are now widescreen monitors, which
are completely different from both 4:3 and 5:4.
 
| The only time you should use 1280x1024 is if it is the native
| resolution of an LCD monitor. If you are using a CRT monitor, do not
| use 1280x1024. Why?
|
| Monitors have something called an aspect ratio. This is the ratio
| between the horizontal and vertical dimensions of the monitor, and
| determines whether the monitor is more square-shaped or more
| rectangular. Virtually all CRT monitors and many LCD monitors have a
| 4:3 aspect ratio, which means if you divide the horizontal size by the
| vertical size, you will get (roughly) 4/3, or 1.333333333… repeating.
|
| Screen resolutions also have their own aspect ratio, which is
| independent of the aspect ratio of the monitor. Fortunately, most
| popular resolutions (800x600, 1024x768, 1152x864, 1600x1200, etc.) are
| also a 4:3 aspect ratio, so when you display them on a 4:3 monitor,
| everything looks normal. Here is the problem: 1280x1024 is not a 4:3
| resolution. It is, in fact, 5:4. Thus, if you use 1280x1024 on a
| normal 4:3 ratio monitor (most CRTs are 4:3), everything will be
| squished vertically because the aspect ratios are different. There is
| no way around this; if your monitor is 4:3, the resolution you want is
| 1280x960, not 1280x1024.
|
| Of course, it’s more complicated than this. Many new LCD monitors have
| a native resolution of 1280x1024. This means that the monitor itself
| is now a 5:4 ratio, so regular resolutions will be wrong. 800x600,
| 1024x768, 1152x864, 1600x1200, none of these will display properly.
| Confusing things even more, there are now widescreen monitors, which
| are completely different from both 4:3 and 5:4.

Understood. But now for the big question. When the accepted aspect ratio for
computer monitors was already 4:3, WHY would LCD monitors come along at 5:4?
Didn't anybody know how to make them 4:3 because of technical limitations? Or
did somebody suddenly decide that 5:4 was better? Most computer graphics were
constructed for 4:3 monitors then, and I suspect that most still are.

So far most of the answers to the 1280 x 1024 question have basically been
"Because that's the way things are." I'd really like to know WHY things are
that way.

Something tells me I may have to keep wondering... ;)

Larc



§§§ - Change planet to earth to reply by email - §§§
 
EDM said:
"For mostly obscure hardware reasons, early DRAM/VRAM
graphics controller implementations favored horizontal
resolutions that were a multiple of the row size. 1280 is
divisible by 256, the row size of a 64K DRAM.

One of those obscure reasons was address translation. If you
form the linear framebuffer address as (2048*y)+x, it made
doing blt hardware much easier: just map x and y onto the
appropriate row and column bits.

Another of those reasons was being able to load the video
shift registers at the same times each line. This made the timing
control easier to do in the logic of the day (think MSI counters
and gates.)

Modern gfx conrollers refresh the display using periodic burst
DRAM access instead of actual shift registers; and they have
hardware to help deal with the x-y to linear address translation.
So the whole issue of row size pretty much goes away."
Click to expand...

Fascinating. Where did you find this?
 
Garrot said:
All standard LCD monitors are 5:4 ratio, the only ones that are not are
widescreen models.
Click to expand...

The standard ration is 4:3. I just measured mine: 4:3 (40x30 cm).
17" and 19" LCD's have a native resolution of
1280x1024, these are the most bought monitors now. That means most
monitors have a 5:4 aspect ratio and not 4:3 as you said. Very few
people buy 4:3 crt's anymore.
Click to expand...

I'm not sure where you live, but the situation is exactly the opposite
everywhere I've seen. The latest monitors still have a 4:3 ratio,
even when they have native resolution of 1280x1024. It's easy to see,
too, since circles are obviously oval on the screen when it is set to
this resolution.
 
Senex said:
Of course, it’s more complicated than this. Many new LCD monitors have
a native resolution of 1280x1024. This means that the monitor itself
is now a 5:4 ratio, so regular resolutions will be wrong.
Click to expand...

This is incorrect. New LCD monitors have aspect ratios of 4:3 as a
general rule, just like old LCD monitors and CRTs. If you set them to
any resolution that is not also a 4:3 ratio of row pixels to column
pixels, images will be distorted on the screen. Fortunately, the only
standard resolution that has this problem is 1280x1024.
... 800x600, 1024x768, 1152x864, 1600x1200, none of these will display
properly.
Click to expand...

They aren't necessarily the native resolution of some monitors, but
they display with proper proportions, at least.

It looks like some people still are confused by resolution issues.
 
Larc said:
Understood. But now for the big question. When the accepted aspect ratio for
computer monitors was already 4:3, WHY would LCD monitors come along at 5:4?
Click to expand...

They wouldn't. The LCD monitor screens still have a physical ratio of
4:3.

I do wonder why 4:3 LCD screens are being made with native resolutions
that don't match the aspect ratio, though (such as 1280x1024).
Didn't anybody know how to make them 4:3 because of technical limitations? Or
did somebody suddenly decide that 5:4 was better? Most computer graphics were
constructed for 4:3 monitors then, and I suspect that most still are.
Click to expand...

My guess is that a greater number of pixels was a marketing advantage.
Most users (including some in this newsgroup, apparently) don't
understand that 1280x1024 causes distortion on a 4:3 screen--and a 5:4
screen would distort every resolution _except_ 1280x1024 (which is
5:4).

In any case, I shall make a point in the future of only buying flat
panels with native resolutions that matches their aspect ratios.
 
Mxsmanic rattled this off his keyboard on 8/21/2006 :
This is incorrect. New LCD monitors have aspect ratios of 4:3 as a
general rule, just like old LCD monitors and CRTs. If you set them to
any resolution that is not also a 4:3 ratio of row pixels to column
pixels, images will be distorted on the screen. Fortunately, the only
standard resolution that has this problem is 1280x1024.


They aren't necessarily the native resolution of some monitors, but
they display with proper proportions, at least.

It looks like some people still are confused by resolution issues.
Click to expand...


All LCD screens can actually display only a single given resolution
referred to as the native resolution. This is the physically number of
horizontal and vertical pixels that make up the LCD matrix of the
display. Setting a computer display to a resolution lower than this
resolution will either cause the monitor to use a reduced visible area
of the screen or it will have to do extrapolation. This extrapolation
attempts to blend multiple pixels together to produce a similar image
to what you would see if the monitor were to display it at the given
resolution but it can result in fuzzy images.

Here are some of the common native resolutions found in LCD monitors:

* 14-15": 1024x768 (XGA)
* 17-19": 1280x1024 (SXGA)
* 20"+: 1600x1200 (UXGA)
* 19†(Widescreen): 1440x900 (WXGA+)
* 20†(Widescreen): 1680x1050 (WSXGA+)
* 24†(Widescreen): 1920x1200 (WUXGA)
* 30†(Widescreen): 2560x1600
 
| Here are some of the common native resolutions found in LCD monitors:
|
| * 14-15": 1024x768 (XGA)
- 4:3
| * 17-19": 1280x1024 (SXGA)
- 5:4
| * 20"+: 1600x1200 (UXGA)
- 4:3

Wouldn't you agree there's one that "sticks out like a sore thumb"? That lone
5:4 completely defies logic. There MUST be a reason for it.

I guess we could first consider stupidity and work up from that if there's any
need. ;)

Larc



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They wouldn't. The LCD monitor screens still have a physical ratio of
4:3.

I do wonder why 4:3 LCD screens are being made with native resolutions
that don't match the aspect ratio, though (such as 1280x1024).
Click to expand...


You might want to measure a screen, they don't all have 4:3
physical ratio. I do recall measuring one of the 19" I
have, it's very close to 5:4, probably spot-on, not 4:3.
 
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