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New arcade vga on pc monitor pics, Not impressed at all.
Xiaou2:
Nick G,
Define Scanliine. Looking at my arcade monitors under magnification, and there is not such
lines seen.
The only thing that I consider a scanline might be when you see a video game or pc monitor video-taped and displayed on tv. You see the 'line' of the monitor refresh. And that looks Nothing like what is shown in the effects in mame. The lines shown in mame are the ones you actually see on a monitor - which is the shadow mask.
Shadow masks do not vibrate. It simply is a divider which seperates each of the
Red,Green, & Blue phosphors "clusters" (or pixels).
Shadow masks are fairly thick in arcade monitors and older tvs. They can be seen as black
lines when viewed closely. And under magnification, you can see the actual grill cells.
As far as I recall last time using the RGB effect.. there was no shadow mask added to the effect.
Not to mention, they just dont come close to looking and behaving correctly. I wouldnt call them
"Close" at all.
Apperature Grill? I believe that you mean shadow mask.
The bleed is not from the mask.. but the actual RGB phosphors brightnesses. Thier light expands beyond the mask and bleeds and blends with the nearby colors.
http://electronics.howstuffworks.com/tv10.htm
NickG:
As per Xiaou2's suggestion here are some nice definitions of scan line and aperture grille. He has done an excellent job defining shadow mask already.
The following info is from wikipedia, sorry if I am getting OT at all here.
"A scan line is one line, or row, in a raster scaning pattern, such as a video line on a Cathode ray tube (CRT) display of a television or computer. A scan line represents a row of picture elements (pixels) in the image being displayed."
"An aperture grille is one of two major technologies used to manufacture cathode ray tube (CRT) televisions and computer displays; the other is shadow mask.
Fine vertical wires behind the front glass of the display screen separate the different colors of phosphors into strips. Depending on the size of the display, one or two horizontal stabilizing wires are also used, and may be visible as fine lines across the face of the screen, providing the easiest way to distinguish aperture grille and shadow mask displays at a glance. Additionally, aperture grille displays tend to be vertically flat and are often horizontally flat as well, while shadow mask displays usually have a spherical curvature."
It is the aperture grille which is susceptible to vibration. A Shadow mask, being one piece is not. I don't see scanlines either, Xiaou2, merely wished to confirm that they do exist in the signal of any scan line - rendered game.
Aperture grille close up
You can compare the difference with the shadow mask close up in Xiaou2 post with the car close up. As the caption mentions "arcade rgb monitor" yes the shadow mask is much more common to arcade monitors than aperture grilles. So back on topic his close up is probably the effect most of us are after here.
On another subtopic here, I use a multisync presentation type monitor (NEC XM29) that syncs to jamma and a standard resolution arcade monitor. From a non-magnified playing/viewing position my jamma games look great on both monitors.
RandyT:
Scanlines don't exist......riiiiight.
I'm here to inform you that they most certainly and absolutely do. Normal raster tubes draw horizontal lines onto phosphor with varying persistence properties, using a focused electron beam guided by magnetic fields. It starts at the top of the screen, drawing line by line until it reaches the bottom, where it snaps back up to the top to start again.
The higher the horizontal frequency, the more lines there are to "paint" on the phosphor, and therefore the less space present between the lines. A low horizontal scanning frequency, as used by CGA or NTSC monitors, will have very visible black lines between the scanlines.
If there were no such things as scanlines, your NTSC TV couldn't uses interlace to vertically offset the starting point of the scan in order to fill the spaces in between them.
If you don't clearly see horizontal (or vertical in the case of a vertically oriented screen) scan lines on your low-res arcade monitor, the EB gun is out of focus... or your eyes are.
RandyT
AndyWarne:
I would not disagree with most of what has been said on this thread.
Yes the graphics certainly do look more "blocky" because the original games were such a low resolution and they are not being smoothed out by the effect of stretching.
I think actually there are two categories of game.
The first type are the games where the designer drew out the character sprites on squared paper and then they were mapped into a ROM. Galaga, Pacman etc.
I believe these games are simply better at native resolutions with the AVGA, no question about that in my mind. On my 31Khz monitor in my Sega cabinet these games look fantastic. Horizontal movements are much smoother as well which is another benefit of the native mode: correct vertical refresh rate.
The second type are the games where artwork has been produced and then scanned at a fairly low resolution. If these are run at native resolution they do appear to be more blocky and for these graphics using stretch blurs the picture slightly but smooths out the blocks and gives a picture which is easier on the eye.
The difference is akin to HD-TV against conventional. HD looks great with the right kind of source but with a poor source, lower definition might be better for some people.
I will try to explain the benefits more clearly on the site to ensure people are not being misled.
Andy
RandyT:
--- Quote from: AndyWarne on September 15, 2006, 12:56:40 pm ---I think actually there are two categories of game.
The first type are the games where the designer drew out the character sprites on squared paper and then they were mapped into a ROM. Galaga, Pacman etc.
I believe these games are simply better at native resolutions with the AVGA, no question about that in my mind. On my 31Khz monitor in my Sega cabinet these games look fantastic.
The second type ....<snip>
--- End quote ---
It's not surprising that they look great on the 31khz monitor in your Sega cab (Sanwa is it?) There is a big difference between the dot pitch of an arcade monitor and that of PC monitor. On larger arcade monitors the dot pitch is somewhere around .75mm. Most PC monitors have a dot pitch that is roughly one third of that. The large dot pitch allows the edges of the pixels to blur together and that just doesn't happen with a modern PC monitor, even though both are capable of scanning at the same 31.5khz frequency.
This is true regardless of the way the game was designed. Either the graphics were intended for the gross dot pitch of an arcade monitor, or they were not.
--- Quote ---Horizontal movements are much smoother as well which is another benefit of the native mode: correct vertical refresh rate.
--- End quote ---
No argument there.
--- Quote ---The difference is akin to HD-TV against conventional. HD looks great with the right kind of source but with a poor source, lower definition might be better for some people.
--- End quote ---
I'm not sure of the point you are trying to make with this analogy. The PC monitor is the "HD-TV" and the arcade graphics (all low-res arcade graphics, in fact) would be considered the "poor source". A good HD TV will incorporate some rather impressive upscaling technology to smooth out a low-res source. It doesn't try to sharpen the blocky edges.
RandyT