6600GT has too much shimmering!

Discussion in 'Videocards - NVIDIA GeForce Drivers Section' started by raul100, Jun 18, 2005.

  1. flexmaster

    flexmaster Maha Guru

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    So it only happens to you when the picture is in motion, does it happen when you set negative LOD bias to clamp in the control panel cause that is exactly what it is for and what it fixes, just read the description in the control panel.

    Tell me if this helps
     
  2. tomilius

    tomilius Member

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    Doesn't help, thanks though. I think I've said before Negative LOD bias clamping does nothing for me in terms of this problem (it is when the scene is in motion). Last post I said I'd update after I tried something. I'll just repost though--I'm checking something in terms of GTA:SA. I'm going to force Trilinear mipmapping on and force AF off and see if it actually mipmaps and that ground texture outside always looks bad or if it really doesn't do any mipmapping.

    Again about the Negative LOD bias thing, that really bothers me that little thing it says in "What's this," because that's the point--AF has been, in some cases, CAUSING unwanted aliasing as I've perceived it in terms of this shimmering!

    OK, results on the GTA: SA thing. Forcing AF does make it use mipmapping, but even in the mipmapping those certain textures (like the ground outside the safe house and the road) look TERRIBLE and COMPLETELY aliased whereas others look blurry in the distance (characteristic of mipmapping) but still smooth.

    So anyway, with any mipmapping for me, GTA: SA makes those textures totally aliased and shimmering (forced AF off). Same thing with forced AF on. I'm actually starting to remember my Ti4200 making that ground look really aliased when I forced AF off, I think, but forcing it on or letting the game put it on never had these issues with that card.

    Those specific types of textures look aliased, to be clear, with AF forced off or on in GTA: SA, but not with it in-game on (except for some shimmering), and all the other textures react normally to AF or mipmapping.

    Did you read the part I wrote about the "blue frames"? See http://usera.imagecave.com/tomilius/blue-frame-diff.PNG.
    Notice how in the "blue" frame, the black splotches on the ground aren't visible. The blue frame was part of the video clip that I edited out, a result of a framebuffer capture being taken before the frame was fully rendered (or something like that). The frame after a blue frame in the video was the same frame fully rendered, so it's perfect for comparison. In other words, do you think this might have something to do with the way games use multiple textures and an optimization in that regard? I don't really know.

    Also, notice even with AF forced off in GTA the double-yellow line on the street outside of the safe house remains sharp, whereas on some other streets without the aliasing it gets blurry in the distance as you'd think it would with mipmapping. Curious.

    As for Guild Wars, there is a bit of shimmering with just mipmapping even, but the textures aren't horribly aliased like those certain ones were with GTA: SA with mipmapping.

    To verify it's not my monitor itself, I tried looking at the clips on another CRT; it's not. I'll try GTA: SA itself on my sister's Radeon 9600 sometime later, possibly tomorrow (well, much later today, we're talking at least 13 hours from now, hehe) if I can get her off her computer.

    Don't ask me why because I don't really know why, but notice how this particular game street smooths itself so nicely (looks blurry, I know, but still) with mipmapping, whereas other textures nearby, lik the sidewalk and the white brick, become quite aliased (the brick shimmers, the street doesn't). Actually, the street does shimmer but very minimally, which leads me to believe once more it's another algorithm type thing. It's odd, but certain textures don't seem to "blur" like others do. Instead, they just get more and more aliased. Maybe it still IS the texture that causes it and nVidia just doesn't handle it as well in the newer cards. Your guess is as good as mine.
    [​IMG]
     
    Last edited: Jul 22, 2005
  3. vatosky

    vatosky Guest

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    I dont get the point of your post :(
    Can you explain?

    All I did was:
    -installed graphics card
    -installed ** driver
    -Oc'ed the card
    -AF:2
    -play the damn games.

    What did i do wrong?
     
  4. tomilius

    tomilius Member

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    Maybe you didn't read any of my rambling, but I've said it time and time again--at LEAST in GTASA and some (or all since flexmaster was able to reproduce this when he started reading my posts a bit more) Series 6 cards (I think flexmaster is on the wrong track with the Brilinear thing) forcing AF via the driver (on or off) causes aliasing like that you've shown. For me, the moire patterns are never quite removed, though, and there's always a certain degree of shimmering on some textures. Try setting AF on a per-app basis and for aliased apps choose to have the app decide the AF.

    If you ARE letting apps choose (or setting it ingame), check the Performance and Quality settings in the nvidia control panel to make sure it's not being set there anyway and is set to let the application choose.
     
    Last edited: Jul 22, 2005

  5. {HLH}

    {HLH} Guest

    its called motion blurr.....
     
  6. flexmaster

    flexmaster Maha Guru

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    Hmm looking at your information I cant see whats wrong, the textures don't blur they are filtered and the image you posted is not bad anistropic filtering its simply weak anti alising, the "shimmering" you see in that picture is simply alised and nothing and anistropic filtering doesen't fix ati alised edges, anti alising does (It was the same on my 9600 pro anti alising had to be simply turned up). And about the blue frame, I believe its simply a picture of that spot before it was rendered all the way, and those black spotches have to be there they are there with every graphics card and I don't see any change in shimmering between the blueframe and the other frame its just simply darker.
     
  7. raul100

    raul100 Member

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  8. flexmaster

    flexmaster Maha Guru

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    Hmm so the 7800 series has even more shimmering than the 6 series according to that link, can anyone confirm this with their 7800 GTX.
     
  9. tomilius

    tomilius Member

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    This is a long post with many images so there's some headings.

    *ahem*
    No, it's not motion blur, thank you. And I would definitely consider the effect on the street texture a blur-like effect because I didn't know what else to call it.

    flexmaster, my point is WHY does the street texture have that blurlike effect with mipmapping the further in the distance it is (that snipped was in the distance in a larger screenshot), and WHY doesn't the sidewalk, or that brick wall, or the ground texture outside of the first safe house, or the road texture next to that? My God, I'm sorry, but can you please read? I write a lot for the purpose of clarifying but people don't seem to even look at it.

    It's not supposed to show weak AF because AF isn't even applied. AF is forced off, however, and because of that certain textures aren't smoothed over with mipmapping or AF or anything, apparently, as you can see (the sidewalk, at least).

    To clarify FURTHER, look at the black lines on the edge of the sidewalk. They maintain sharpness and aliasing even into the distance, whereas the double yellow line in the middle of the road there, in the distance, has a blurlike effect and does not become aliased.

    ENLARGED IMAGES--Street Texture Same with AF via Driver or Game, Sidewalk Not--Difference in Texture Rendering Technique or Multitexturing?--Repeat, Ti4200 could have AF forced on without such penalty
    OK, here's a comparison between forced AF and in-game AF. Red marks signify differences to point out, and green marks signify something that's the same that I'm pointing out (the street); click to see without marks:

    Forced AF (16x):
    [​IMG]

    In-game AF (who knows, probably 16x but handled correctly):
    [​IMG]

    Again, I did my best as far as the angle goes--it's not exact, but since I use my Xbox controller and was too lazy to switch temporarily to mouse and keyboard, I couldn't really get it exact. I can understand how someone might feel the angle is the sole cause of any difference, but having played in-game, I can say the sidewalks really don't appear smoothed with forced AF since it's done horribly as you can see by the moire; the lines aren't all-over smoothed on the left sidewalk--the sidewalk on the right side of the street is much better than the left but as you can see from the in-game AF it's still not as smoothed as that.

    The red rectangles on the in-game AF image show how the anisotropic filtering works differently and how the smoothing works the way it should, at least compared to the image with forced AF. The lines, being in the distance, aren't prominent like they are in the forced AF image, and that's what I tried to point out.

    Were there some moire patterns with the in-game AF? You bet! But not so much that far in the distance and never nearly as bad. You have to understand that the enlarged images I've shown are from near the very top part of a 1280x1024 screen and, if I were to reckon in-game distance, at least 25 meters away from the camera. I'm bad at that sort of reckoning, but it's at the end of a block the camera doesn't even begin on.

    Notice how the street in both images (attempted to be taken from the same angle but at least taken from the same distance) looks about the same. The way anisotropic filtering applies to the road is pretty much no different, and they both even start to "fade out" smoothly at the same distance (before the double yellow line ends). However, if you look at the sidewalk in both images, in the one with AF forced on you can see the anisotropic filtering used to smooth it is much crisper in a bad way. The in-game AF handles the sidewalk much better, however, with the lines, at such a distance, blended in with the gray of the sidewalk as they should be and not so prominent. Therefore, forcing AF on in GTA: SA increases moire patterns on these certain textures as well.

    REGULAR IMAGES of Texturing Comparison
    And now for some not-enlarged images (click for their PNG counterparts):

    Forced AF:
    [​IMG]

    In-game AF:
    [​IMG]

    Notice once more the darker, more prominent lines on the sidewalk even in the distance with forced AF, and realize that since it's just a small clip out of a 1280x1024 screen, it IS noticeable when playing. I think the sidewalk has a texture-rendering mechanism similar to that of the ground outside of the first safe house considering how the street in the center looks almost exactly the same with forced AF or not if you ignore the angle and reacts as one would think it would to normal mipmapping as well.

    IMAGE--Texture Differences with Mipmapping Too
    Maybe you can see what I mean about the mipmapping in this image and ANOTHER explanation:

    Trilinear mipmapping (no optimizations, AF forced off):
    [​IMG]

    Notice how the double white line simply blends into nothingness as it goes into the distance with no aliasing at all. On the other hand, the sidewalk's moire pattern gets worse rather than reacting as one would expect it to to mipmapping--rather than reacting how the street does. The street outside of the first safe house with the double yellow line--its yellow lines don't "fade" out like that double white one or the yellow one seen in other mipmapped image as they go into the distance because its texture is rendered the same way as the sidewalk is. That's the way I see it.

    I'm curious as to why that needs to be confirmed. Don't you trust BeHardware? :D

    Saying so much without knowing what you're talking about but without a hint of uncertainty isn't going to help us make any progress. In the future read my whole posts. Please. Anti-aliasing does not help reduce the "shimmering" or the moire patterns that you're referring to as shimmering because the moire patterns are part of the way the TEXTURE is rendered, and the texture has no edges that anti-aliasing would look at unless it was supersampling anti-aliasing, but even then the moire patterns wouldn't be completely eliminated and the shimmering is barely reduced at all (I've tried it). Besides, the shimmering can only be seen in motion. That's what shimmering is.

    IMAGE--Antialiasing/Supersampling Doesn't Fully Eliminate Moire or Shimmering But Helps
    Because I'm on a roll, here, I'll add in proof that 8xS doesn't fully eliminate moire patterns. I can't prove it doesn't eliminate my shimmering problem without taking another video though, but it doesn't fully (though it's certainly not very noticeable since the framerate is so incredibly low anyway and because it's supersampled), especially since I have the AF forced here.
    [​IMG]

    The Guild Wars shimmering is not eliminated either, though it is reduced.

    IMAGE--Black Splotches NOT in Partially Rendered Frame--Multitexturing the Reason?
    All I have at the moment to use is paint since I just reinstalled Windows but I inverted the colors of the image to help you realize the black splotches are not there (with inverted colors they'd be white but still noticeable). The ground is probably multitextured.
    [​IMG]
     
    Last edited: Jul 22, 2005
  10. particleman

    particleman Active Member

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    There were some really long threads about this issue on nvnews when the 6800 was first released. Eventually nVidia released a driver with the negative LOD clamp and that seemed to help fix the problem in most games, but not all. It also resulted in slightly blurrier visuals in some games. The shimmering is not due to any brilinear transition optimization, because the 5900 did not have this problem. The root of the problem is on cards after the 6800 nVidia does not take enough texture samples for the level of AF being applied, and their mip map blurring is insufficient on certain mip map layers. On ATi cards the problem isn't entirely non-existent, it is to the point where it isn't noticeable in most case and much much less compared to the 6XXX and 7XXX cards.

    Anyways the two settings that I find which help fix the shimmering most are the Image Quality setting: always turn it up to High Quality (HQ isn't the same as quality with all optimizations disabled), and turn on the negative LOD texture clamp.

    Here are some really long nVnews threads on this from last year, there are a few people that insisted they didn't notice it but there are A LOT of people that have noticed the shimmering.

    http://www.nvnews.net/vbulletin/showthread.php?t=35592&highlight=shimmering

    http://www.nvnews.net/vbulletin/showthread.php?t=38888&highlight=shimmering
     

  11. tomilius

    tomilius Member

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    Thanks very much, particleman, for the links and the valuable info. :D Quite possibly the most useful information about this problem of any I've seen.

    Had a read of the other threads and posted in some nV News ones related to the problem. We're definitely not alone.

    nV News Forums - Drivers use nearest neighbor filtering ...

    I have to say, with High Quality for Image Quality and RivaTuner set with a 0.5 LOD bias (yes, positive, to smooth it out more not sharpen it), things are better and the shimmering is just barely noticeable, and I think I could learn to ignore it. Still, I will definitely consider buying another nVidia card, ever, much more critically for this kind of junk.
     
    Last edited: Jul 23, 2005
  12. Darren_Hodgson

    Darren_Hodgson Master Guru

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    I must admit that I've not really noticed shimmering much in PC games but it was one of my pet hates about console games, PS2 ones especially.

    Then I bought GTA: San Andreas on PC, ironically a PS2 port, and I was shocked at how appalling the shimmering problem was in the game even with anti-aliasing set to full and mipmapping on via the ingame settings. No amount of tinkering with the AF or AA would eliminate the 'ugliness'. However, using nHancer and using 4x4 supersampling seems to have drastically improved the image quality and now the road markings at mid-distance onwards no longer look jaggy. Even the overhead cables no longer look excessively jaggy, something even 8xS AA from the control panel couldn't even get rid of.

    Now at least I can play the game without the visuals becoming annoyingly distracting...
     
  13. raul100

    raul100 Member

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    I thought I have already posted these links here before.

    Others:

    http://www.hardforum.com/showthread.php?t=821421&page=1&pp=20

    http://www.beyond3d.com/forum/viewtopic.php?t=16196&postdays=0&postorder=asc&start=0

    http://forums.guru3d.com/showthread.php?s=&threadid=107410&highlight=shimmering
     
  14. tomilius

    tomilius Member

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    In this thread? Didn't see the other Guru3D one. Plus I'm blind.

    You'd better believe this problem will never be fully solved. We'll have to try our own solutions. As I said, for myself, it does make things a little more blurry but 0.5 LOD bias helps (in that last Guru3D thread it said 0.3 but 0.5 reduces most shimmering best for me I'd say). But that's along with all of the other precautions for GTA: SA if that's the game I'm playing (no forced AF, Visuals at High or Very High when game starts).

    nVidia would have fixed this problem if it were possible by now. It's not like they couldn't notice something like this. They did it obviously to increase performance in hardware at Image Quality's sake. And as long as there are jerks around here that act like there's no problem (or maybe there really isn't for them but that would be kind of complicated and wouldn't make *cough* some of them any less of jerks for the horrible way they say there's no problem), nVidia will be nice and shielded from the issue by denial. People all around saying, "It's that way with every game," "The textures are bad in that game." Give me a break, seriously, and read the information using logic before making such statements.

    Oh, gee, sorry, got a little carried away there. ANYWAY, I think I've actually seen shimmering-type stuff in console screenshots as somebody else mentioned somewhere. Even next-gen console shots perhaps. That is, having little patches of areas aliased with the rest looking like anisotropic filtering went over it. But that's just from memory, I could be wrong about the next-gen thing, plus the stuff wasn't in motion so how could I tell (some stuff obviously looked aliased, but I mean the stuff that looked like it had AF applied still appeared to have some areas where shimmering must have been).

    Don't expect this problem to go away in the near future, anyway. When they're able to reach a near-"free" point with anisotropic filtering in terms of performance, thenn nVidia will probably advertise the normal, regular anisotropic filtering we had on our FXs and Ti4200s as a NEW feature, like "UltraSmooth Anisotropic Filtering Deluxe," or something. "An unprecedented gaming experience for brainless blind people who can't tell the difference anyway and individuals with multiple eyes who've been pissed off." With all of the people out there that "don't have the problem" .. OK, *ahem*, sorry guys. I can't really define your visual quality for you. .. but your psychologist can ;).

    For now, look around, especially for info specific to the game you're having a problem with, and apply tweaks people recommend to see what works best for you. Setting Image Quality to High Quality, for me, sometimes seems to have a performance improvement and otherwise there's not much difference. If the fps is ever lower, it's not by much. And remember to adjust the LOD bias (upwards) as that will help all-around with the problem.
     
    Last edited: Jul 23, 2005
  15. raul100

    raul100 Member

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  16. tomilius

    tomilius Member

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    That's one of the street textures that causes problems (and then that sidewalk texture in the second image causes problems too as does just about every sidewalk texture I'm sure). Even if you force off AF and trilinear filtering should set in, the double-yellow line on that street will not "blur" out... trilinear filtering will not be applied to it, and it will remain crisp and sharp off into the distance. Not a problem with the double-yellow line/street, but other textures do it too. Of course, that's only with forced AF (on or off).

    The in-game AF is 16x for me (it must be from my comparisons). I think it uses the max your card is capable of, maybe with a Visual quality above Medium... maybe. I know those textures will always look that way no matter what with a Visual quality of Medium or below (for me)--that is, unless it's with my Ti4200, and then I don't remember fully. My dad has the Ti4200 so I'll get the opportunity to take a look this weekend and probably get some shots.

    Again, notice how certain streets look the same between in-game AF and forced AF. Because of this, I think it's the way the game does it, at least "to some extent." The game probably knows that the way some cards handle anisotropic filtering is very bad, so when you don't force it on yourself, maybe it gives AF a clue somehow. Of course, there's still a bit of shimmering no matter what, but when it "gives AF a clue" (and you let it), it certainly helps with those "difficult textures."

    I can't say much more about it than that at the moment. I've said a ton about it already, and taken a ton of screenshots and made comparison images (with Paint, kill me) and a couple videos (aniso-death.wmv is of poor quality and not as demonstrative as auto-af.wmv), but... anyway. That's it from me until I get results from my old video card or somebody tries to hurt my feelings or has something to say that I want to comment on. Hehe.
     
  17. raul100

    raul100 Member

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  18. tomilius

    tomilius Member

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    This probably won't mean very much, and I have little need to take screenshots or videos (the only difference is there's no shimmering, easy enough to understand).

    The most important things I can say is that I can confirm with the Ti4200 there's no difference between AF forced via the driver and AF automatically enabled in-game (forcing it on via the driver does not cause aliasing as in the 6 Series). However, with AF forced off or the in-game quality below High when the game is started (it may be switched to Medium/Low in-game without the effect occuring), the aliasing on those same certain textures WILL occur.

    So, here's a sort of list of what I've found out:

    Ti4200 Tests
    ------------
    GTA: SA:
    In-game Quality on Low/Medium = Aliased Shimmering on "Those" Textures (regardless of other settings)
    In-game Quality on High/Very High:
    (Image Quality: Quality)
    AF Left Alone (Application Preference) = No issues, smoother anisotropic filtering than 6600GT
    AF Forced On = No issues, smoother anisotropic filtering than 6600GT
    AF Forced Off = Aliased Shimmering on "Those" Textures
    AF Forced Off, Trilinear Forced = Aliased Shimmering on "Those" Textures
    Negative LOD bias Clamp/Allow = No effect
    (Image Quality: High Performance)
    With No Issues Otherwise (Generalization/Approximation) = Perhaps a slightly increased amount of shimmering, similar to 6600GT at High Quality

    While due to the nature of pixeled rendering it would be unfair to say shimmering is entirely unpresent, the shimmering effect is much less visible except at lower resolutions.

    Guild Wars (Generalization/Approximation):
    IQ: Quality
    No shimmering with AF forced on or off.
    IQ: High Performance
    Shimmering noticeable 1/3 the amount of 6600GT in Quality

    Shimmering only seemed to barely begin to rear its ugly head at 1280x1024 with High Performance chosen for Image Quality. However, shimmering was noticeable at resolutions lower than 1280x1024. At 1024x768, the shimmering (NOT the shimmering as in the aliasing on certain textures in GTA: SA but shimmering on certain textures in any game) was about 2/3 as noticeable as the shimmering at 1280x1024.

    The image is overall noticeably smoother regardless of any barely-noticeable shimmering in the Ti4200. All of this data was gathered via my old Ti4200... obviously... and observations were made on a 19" LCD rather than my 17" LCD at home, in case that actually has a bearing (I doubt it, shimmering is visible in my videos when I view them on this monitor).

    There's a difference in the shimmering I see in the Ti4200 if I ever see any. It's not a pixel "jumping." It's a less noticeable, smoother pixel "sliding" on the texture if I ever see it. I've taken a video (large and uncompressed now) but it's at a much lower fps and will need to be cropped/compressed if I'm going to be uploading it (if anybody wants me to). So yeah, you'll have to request that. I'm too lazy.
     
  19. g0o

    g0o New Member

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    wait for the next AGP card nvidia releases
     
  20. tomilius

    tomilius Member

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    Is that a joke? :D
    They're not releasing any new AGP cards, I thought.
     

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