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Trick with using PC CRT
RoomTenONine:
Randy, thank you so very much for the insightful posts. I've learned something here and that is awesome! :cheers: to you!
Ummon:
Um, Xiaou2, while the exchange between you and Randy is illuminating in ways, I ask you don't get too involved in it here.
--- Quote from: RandyT on July 15, 2008, 01:09:18 pm ---I just checked out the video options in ZNES...But for the most part, these type of effects, sans the active "jitter" effects, can already be applied in MAME.
--- End quote ---
Really? I don't like it anyway, but I didn't know Mame could do that.
@Room: running my integrated Intel video, I didn't have any trouble with the NTSC effect or any other filters on ZSNES. Although I did have trouble with running the particular rom I found. Not that it matters, as I just wanted to see the effect, which you can demo from the fe main screen. The NTSC effect is pretty decent.
--- Quote ---The negative effect of low resolution can be seen quite clearly by noting the difference in quality between a 640x480 screen res and one that is 1280x960. The extra resolution allows for things like bleed and scan line simulation, as well as non-sharp-cornered pixel representation. At 640x480, these effects fall apart as they have inadequate space in which to perform.
--- End quote ---
And at 640x480 on a PC CRT, there's already hardware scanlines. Ginsu, get that ZSNES emulator and start it. By default, it should display at 640x480. If it isn't, set it there. When it is, there should be very noticable hardware scanlines due to the resolution. Just like if I set the desktop to VGA, or run a Mame game with at VGA+hwstretch. If not, then I have no idea. Below are some camera pictures of what it looks like. For the 640x480 pics, you may need to save and view at high resolution as the lines are fairly fine. Actually, I just viewed them, and it's hard to see - but the ZSNES 640x480 pic I think it is visible.
-- using the original posts settings:
- bubbles
- DK horizontal orientation
- DK vertical orientation
--using ZSNES
- 25% scanlines
- NTSC composite
- NTSC s-video
- NTSC rgb
- no effects, resolution configuration = 640x480 SF (stretched, full screen)
Ummon:
By the way, Ginsu, here are my ini files.
Also, remember that one can create high refresh modes (31khz, 120hz) and get hardware scanlines, as seen below. (Afte clicking the thumb, click on the picture to magnify.)
RoomTenONine:
--- Quote from: Ummon on July 17, 2008, 09:09:48 pm ---
--- Quote from: RandyT on July 15, 2008, 01:09:18 pm ---I just checked out the video options in ZNES...But for the most part, these type of effects, sans the active "jitter" effects, can already be applied in MAME.
--- End quote ---
Really? I don't like it anyway, but I didn't know Mame could do that.
--- End quote ---
I don't like any of the presets for it, but I've achieved something very close to what I personally want out of such filters. That being an image that has scanlines that looks like it is from a properly calibrated high quality SD 4:3 TV circa the mid 90's. That is the type of TV I played all my consoles on and that is waht I'd like to emulate. I've done so successfully with the NTSC filter and custom settings.
Although I get similar results in advanceMAME, it isn't the same there is a big lack of control/tweaking options compared to ZSNES...unless I'm missing something. Perhaps Randy could explain further on how to achieve this??? Pretty please?
--- Quote ---@Room: running my integrated Intel video, I didn't have any trouble with the NTSC effect or any other filters on ZSNES. Although I did have trouble with running the particular rom I found. Not that it matters, as I just wanted to see the effect, which you can demo from the fe main screen. The NTSC effect is pretty decent.
--- End quote ---
You shouldn't have issues. All the issues I've ever had with it were due to nVidia drivers. It still works 100% the GUI just crashes when you enable it (or HQx). I jsut have to turn it on using the config file, then all is good in the video menu.
Xiaou2:
This is a really bad way to think about this....
Ignoring the fact that if you subscribe to this conclusion, you must also subscribe to the idea that the entire image is an illusion
That is exactly what I was getting at. Most of what is seen is an illusion.
The difference is that I am saying is that what a person is seeing is not an
actual line from the drawing - but instead, the lines are simply from the
shadowmask instead.
Your brain can only process visual imagery so quickly, which is why you can watch a movie with 24 frames per second separated by blackness and see moving imagery without obvious flicker. We can argue all day long about whether something is real because we can only perceive it as such, but the plain fact is that lines are created, and we can see them.
If they are going so fast you cant see them... are you really sure you are
seeing them? Or is it really just mostly the shadowmask + the illusion
of the darks and lights throwing off your perception?
As the beams move horizontally across the screen, and have physical space separating them, there are indeed lines formed by the scanning. Scan lines is a real term and it refers to exactly the thing that you would expect it to refer to; lines created by the scanning method. Even very high frequency displays have them, but they are far less apparent because they are spaced much tighter together.
As far as I understand it... As the electron beams pass, they Re-Illuminate the phosphors. Each lit phospher will darken at a set rate. The beams do not create
the darkness... instead, that darkness is the phosphors darkening on their own.
Quote
What is also interesting... is that each R,g and B pixel area... can be lit up fully, or in part. Thus, you see examples where 1/4 th the red pixel dot is lit - while the rest of it is dark.
Again, this is absolutely minimized on a properly adjusted display. If another color is being consistently illuminated when it should not, even partially, you have "color purity" issues.
Strange, because my 27" CRT TV, capable of 480I, which really doesnt get too
much use and is in near perfect condition shows the same traits under my 5x
magnification loop. The individual RGB phosphors can be partially illuminated.
Look at moving images yourself under magnification. Anyone can see it...even on
brand new lower-res CRTs.
You get orange by mixing less green with the red.
Yet, in the pics I see that Red alone is let up to be orange. Green is not
needed.
Bright blue is achieved by mixing equal parts of red and green with high intensity blue, thereby adding a higher "white" or intensity component.
My mistake. I see in the pic that they used green and blue to create the
light blue / canyon color in turbos tires. There was a hair bit of red too, but
mostly dominant green and blue.
If you are getting orange from your red gun, it is simply because the gun is no longer properly aligned with the shadow mask, or the gun is so severely out of focus it is creating muddy color by bleeding into the surrounding colors. You are describing the characteristics of a "broken, or maladjusted monitor", not a properly functioning one where these things are much, much more well controlled.
Not so sure about this. I think the effect is simply the red being brightened to the
point of appearing orange. I will confirm it against my good new tv when I
get the chance however.
Usually, the dot pitch of a monitor is pretty closely matched to the scanning capabilities of the tube. It would make no sense at all to have a very fine dot pitch on a display that was capable of scanning at only 15.75khz (CGA) as it would be a more expensive component that is never taken advantage of. This is why you see large dot pitches on TV's and Arcade monitors and small dot pitches on PC monitors.
How would you know about what these costs factors are? Hes a hypothetical
reasoning:
THey make a lowres monitor that have a large dot pitch.. however, in a year
or so, they improve the ability to make more precise masks. This may help cut
down on possible degradation effect over the lifetime of the unit.. and may
reduce bluring and bleeding.
Games made before that change were designed to utilize the certain qualities
of the larger dot pitch. However, newer games could be designed to use
the slightly crisper qualities of the newer monitors.
It may be possible that the extra resolution was cheaper to make, as they
may have been using that same mask on other non arcade Tvs.
They could have simply just altered the arcade guns positions to skip over the
extra lines that were no to be used. OR, it simply scaled the picture, using 2 or
more rgb groups for what was one group before.
All I know is that last time I looked at the new low res monitors... their dot
pitch was higher than those of the past. One has to conclude that the
display output must have looked different because of it.
The dot pitches are not especially smaller today for the same frequency of display, but you will probably be less likely to find the traditional dot triad type of mask.
- Well, if you are trying to say that the frequency controls where the
lines are drawn... then that would further my argument about exaggerated
appearance of black lines. (skipped/unused pixels)
If not - it still does not consider the different look no matter what.
While this is true, they were not drawn with a malfunctioning display in mind. In fact, some graphics were so meticulously planned to take advantage of the way CRTs work that anything but a properly functioning display would cause the graphic to turn to "mud", not terribly unlike that representation of the Turbo car you are showing.
The pic is a jpeg in magnification. At regular distance, and in person, the monitor
looks pretty darn good.
I can dig up Tons of arcade photos of real machines that show how much
color variance difference there is between svga and an arcade CRT.
Simulated lines do not capture that difference at all.
Now, we can simulate this look using various methods... however, it will have
to be much more complex than some stupid Overlay effect. We know that if we take a picture of an arcade monitor, and or vector.. we can then view them on our
pc monitor and they look accurate. Even at fairly low resolutions compared to the
supposed ridiculously high res that you THINK you need to pull it off. At
a mere 1024*768, you can view an arcade pic full screen and have it look
very authentic.
The extreme would be a raytrace routine that would render the shadowmask
and the phosphors and calculate all the light rays bouncing around.. then
render that and scale it to the correct size.
However, that would take way too much processing power to do on the fly.
A step seeming more achievable, would be to create a ruleset routine of how to
alter the pixels color and brightness depending on its nearest neighbors.. as well
as other factors too. It would then take the high res drawing and again,
scale it to the resolution needed. (probably no less than 1024*768)
My biggest point, is that simply overlaying some dark lines over a
picture does not make it look anything like a true arcade display.
Also.. that newly made monitors made have been altered to the point where
they really do not match the look of the original monitor when it was new.
There is a market, for a device or software solution that re-creates that
arcade quality look on a PC monitor or LCD. Especially with CRTs being expensive,
bulky, electric prices rising, EMF radiation, and finally, CRTs being phased out.