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-   -   Someone please show me the difference in image quality on a ATI 9700 pro vs a GF4 ti? (http://www.nvnews.net/vbulletin/showthread.php?t=2720)

imtim83 10-10-02 09:18 AM

Someone please show me the difference in image quality on a ATI 9700 pro vs a GF4 ti?
 
Ok here is a pic of unreal 2003 retail with my Leaktek GF4 ti 4400 overclocked to GF4 ti 4600 speeds. I am running unreal 2003 at 1600x1200 with all details on maximum. Please someone with a ATI 9700 pro on the same map and area with 6x or 4x FSAA and 16x AF on show me the difference with a pic. I don't see a difference in the pics on some reviews. I just can't see the difference. I want to but i can't.

Thanks


http://members.cox.net/imtim2/pic

Raptorman 10-10-02 03:31 PM

I have a Radeon 9700. I will try and get you a pic before the night is over.

thcdru2k 10-10-02 07:45 PM

it's not really the difference if the image quality, but the power of the r9700 to produce faster framerates of equal image quality. so in a sense, it looks better in motion. i doubt you'd be able to tell a difference from a screenie.

SnakeEyes 10-11-02 11:14 AM

With the settings he mentioned, I'd have a hard time believing the 9700 isn't faster in UT2003. CPU limitations aside, that is. ;)

StealthHawk 10-11-02 06:18 PM

can someone with a R9700Pro please benchmark Tenebrae Quake on a number of different resolutions?

Chalnoth 10-11-02 09:24 PM

From what I've seen over at Beyond3D, the differences are as follows:

1. Radeon 9700 has an anisotropic implementation that's an improved version of what was done on the Radeon 8500. It still will look worse than the GeForce4 at some angles. To me, this makes it worse.

2. The Radeon 9700 has superior FSAA, for three primary reasons:

(a) More speed, due to higher memory bandwidth and other possible optimizations.

(b) Better sample patterns.

(c) Gamma-correct FSAA.

The benefit of the the higher speed is obvious, and the better sample patterns are almost as obvious for those in the known, but I believe both of those actually pale in comparison to the improvment offered for gamma-correct FSAA. Unfortunately, however, the amount by which the FSAA is gamma adjusted is currently not user-selectable, and will therefore be wrong for many people. Still, it is better than nothing.

A quick explanation of what gamma-correct FSAA does: When the voltage signal is sent to the monitor, doubling the voltage will not double the brightness. That is, it's not a linear response. As it turns out, most monitors have voltage response curves that just happen to fit in well with the human visual subsystem, so that while double the brightness isn't being produced, our eye sees it as that.

What this means is that when doing averages, straight averages are actually not the way to go. It is much better to do a reverse gamma adjust before averaging, and then gamma adjust the output. This won't affect the overall brightness, but will affect averages. While it is true that any average done (texure filtering, blending, etc.) should also do this, it really isn't feasible. But, FSAA can show the problems that result from lack of gamma correctness most when viewing wireframe images. Have you ever viewed an image in wireframe with FSAA enabled and noticed that, from a distance, the lines looked dotted? This should not happen with proper gamma.

In sum: The Radeon 9700 offers better FSAA and similar anisotropic (some say better aniso, I say worse) compared with the GeForce3/4 architecture.

Bigus Dickus 10-11-02 10:19 PM

Quote:

Originally posted by Chalnoth
From what I've seen over at Beyond3D, the differences are as follows:

1. Radeon 9700 has an anisotropic implementation that's an improved version of what was done on the Radeon 8500. It still will look worse than the GeForce4 at some angles. To me, this makes it worse.

Following that logic, the GF4 has an anisotropic filtering implementation that looks worse than the 9700 at some angles. Does that mean it makes it worse as well? Are they both worse, since they both look worse than the other in some cases? :confused:

I, like most other people, conclude that if implementation A looks better by 20% 80% of the time, and implementation B looks better by 5% 20% of the time, then impementation A is the better solution, and "looks better" overall. Strange how you reached the exact opposite conclusion.

Chalnoth 10-12-02 01:09 AM

Quote:

Originally posted by Bigus Dickus
[b]Following that logic, the GF4 has an anisotropic filtering implementation that looks worse than the 9700 at some angles. Does that mean it makes it worse as well? Are they both worse, since they both look worse than the other in some cases? :confused:
No, because the Radeon 9700's implementation is inconsistent. It may use an anisotropic degree of 16 on a horizontal surface, but will only use somewhere around an aniso degree of 4 or so on a surface at around the angle of 23 degrees. I claim that fluctuations like this are far more noticeable than the more consistent implementation available in the GeForce3/4 series.

In another manner of speaking, I believe that image quality is only as good as the lowest-quality part of the image. As a quick example, why increase image quality? The entire reason, for me, is so that I don't notice image quality problems (such as overly-blurry textures, aliasing, z-buffer errors, and so on). Since the Radeon 9700's worst-case anisotropic is in the region of 4-degree aniso, I don't consider it much better than 4-degree aniso. By contrast, the worst-case scenario for the GeForce3/4's using max aniso is still their maximum aniso (8-degree).

Bigus Dickus 10-12-02 01:53 AM

So consistency is King then? I suppose 2x SSAA looks better to you then than 6x gamma-correct MSAA? No? What about those cases where an alpha texture might come into the screen? Well, that's the lowest quality part of the image. Using your rather clearly stated logic ("Since the Radeon 9700's worst-case anisotropic is in the region of 4-degree aniso, I don't consider it much better than 4-degree aniso"), you would conclude then that gamma-correct 6x MSAA isn't that much better than no AA? Hell, let's make it 2x performance Smoothvision just to give it some equivalent AA, which isn't all that spiffy IMO.

I mean, hell, sure it's jaggy as can be, but at least it's consistent about it, right? And since it's worst part of the image is better than the 9700's worst part, then it must be the better implementation, correct?

Apples to oranges you say? Why? Because it's a silly argument in this case... but why not in the case of AF?

You know, you had a point back when the 8500 lost all AF on 45 degree rotations, and had only bilinear so the moving mip-map line was actually noticeable (though personally I've never noticed it, not being a flight simmer). Now that trilinear blends the mip-map lines, and there is AF there (and I've seen the screenshots at B3D too, and in the worst case it's just a hair worse than the GF4 is there), I just don't see the argument.

I know you like to stick to your guns, and I know this has always been your trumpet call (lowest part of image defines IQ of entire image... at least where AF is concerned), but perhaps you should do a bit of deep thinking about this. If the AA example doesn't illustrate why, then perhaps we can find another example.

Again, I've seen the SS's at B3D. The 22 degree rotations were nearly identical on the GF4 and 9700 (much less difference than between the 4x and 8x mode of the 9700... though perhaps not between the 4x and 8x of the GF4 as it doesn't seem to do a whole lot more in 8x mode). On the other hand, on non rotated surfaces the difference isn't nearly identical, but very obvious.

Perhaps you're just arguing that a change in IQ, from whatever to whatever, is what bothers you? Then, if the 9700 changed from 32x to 16x (hypothetically) you would still conclude a straight 8x AF is better IQ? What if it chaged from 16x to 15x (not a real possibility, but used for rhetorical value)... would it be worse by virtue of it still changing in IQ, or would it be a "small enough" change to pass your threshold? You can see what I'm getting at here. You've defined your IQ criteria as "lowest quality part of the image" which is obviously silly, or perhaps you are implicitly defining it as being "the most consistent," since you did mention that, without qualifying statements about the required level of consistency, restraints on minimum level of IQ even if consistency is maintained (since you can run with no AA and no AF and have perfect consistency).

It's absurd, plain and simple, but to each his own I suppose.

Chalnoth 10-12-02 03:33 AM

Quote:

Originally posted by Bigus Dickus
[b]So consistency is King then? I suppose 2x SSAA looks better to you then than 6x gamma-correct MSAA? No? What about those cases where an alpha texture might come into the screen? Well, that's the lowest quality part of the image. Using your rather clearly stated logic ("Since the Radeon 9700's worst-case anisotropic is in the region of 4-degree aniso, I don't consider it much better than 4-degree aniso"), you would conclude then that gamma-correct 6x MSAA isn't that much better than no AA? Hell, let's make it 2x performance Smoothvision just to give it some equivalent AA, which isn't all that spiffy IMO.
I've posted on this again and again, and the answer is simple: the alpha test/MSAA problem is solvable through programming. The anisotropic problem is not.

And the other thing is simply that both the GeForce3/4 line and the Radeon 9700 use MSAA, so the point is meaningless here, whichever your stance.

Quote:

Perhaps you're just arguing that a change in IQ, from whatever to whatever, is what bothers you? Then, if the 9700 changed from 32x to 16x (hypothetically) you would still conclude a straight 8x AF is better IQ?
Meaningless. Again, refer to my previous argument. I would consider such a technique little to no better than a more comprehensive 16x anisotropic implementation.

As a side note, I don't believe any current consumer-level video card supports non-power-of-two anisotropic degrees (Every pixel on the screen is either 1x, 2x, 4x, etc.).

Oh, and please stop with the pointless personal attacks. It seems that every argument I make is riddled with personal attacks in return. Try arguing the point for once. If you can't do that, then shut up.

Bigus Dickus 10-12-02 11:51 AM

Quote:

Originally posted by Chalnoth
I've posted on this again and again, and the answer is simple: the alpha test/MSAA problem is solvable through programming. The anisotropic problem is not.
But it's not solved currently so my point is perfectly valid. I suppose then, that if an ATI hardware designer or driver delveloper were to reveal that the 9700's AF implementation could, in fact, be altered through programmability but they had simply not been sucessful at "correcting" the behavior, then your opinion would suddenly be reversed and the 9700 would have superior AF simply because it could be "fixed?" I find that unlikely. Until they actually solve the MSAA/alpha test problem, it's still a problem.

Quote:

And the other thing is simply that both the GeForce3/4 line and the Radeon 9700 use MSAA, so the point is meaningless here, whichever your stance.
Then you agree that the 8500's 2x performance smoothvision is of better quality than both the 9700's 6x MSAA and the GF4's 4x MSAA? Stop dodging the issue.

Quote:

Oh, and please stop with the pointless personal attacks. It seems that every argument I make is riddled with personal attacks in return. Try arguing the point for once. If you can't do that, then shut up.
:confused: :confused: :confused: I've done nothing but argue my point. I recall (and looking back at my posts in this thread) making no personal attacks against you at all. I think your opinion is absurd, but I never questioned your intelligence or anything remotely similar. Trying to cloud the discussion here instead of addressing the point yourself?

Chalnoth 10-12-02 01:35 PM

Quote:

Originally posted by Bigus Dickus Then you agree that the 8500's 2x performance smoothvision is of better quality than both the 9700's 6x MSAA and the GF4's 4x MSAA? Stop dodging the issue.
No. Not on the least. And I personally feel that both nVidia and ATI should be getting on game developers to fix this particular issue.

You should know by now that I prefer to argue more from a theoretical standpoint. From that standpoint, MSAA is most certainly a good thing (compared to SSAA) because it separates edge AA from texture AA. Because the two are fundamentally different, separating the two is necessary for the best performance/image quality ratio.

And as for alpha textures, the games that I play the most right now (Neverwinter Nights and Morrowind) use alpha blends. After I get UT2k3, and once the renderer source is released, I plan to see if I can't go ahead and use alpha blends there, too, just as I did with UT (Btw, alpha blends are used for some surfaces in UT2k3, just not all...though I'm willing to bet it'll be a fair amount more challenging to implement them in the remaining surfaces than it was in UT).


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