10 Replies Latest reply: Sep 26, 2010 10:20 PM by Chris Cox RSS

    Gradient banding in Samsung 20 inch LCD

    NinBuu Community Member

      http://i56.tinypic.com/1z6aa38.jpg

      Now idk where to begin, ok here's the best info i can give

       

      I just assembled a new pc for graphic work/budget gaming 2 days ago:

      intel core i3 530 mhz

      2 gb ddr3 ram 1333 mhz

      xfx nvidia geforce gt 240 1gb ddr5

      windows 7 ultimate 32-bit

      Samsung Myst Eco B2030 widescreen 20 inch lcd monitor

       

      Now when i opened an old psd which contained some brushing and gradients, i could see bands in the gradients, even the wallpaper i put had bands on it. I even noticed that everything on my lcd looks hellish sharp, and when i force my head really close, i can see small square pixels all over the l cd. Is it due to the analogue output(VGA)?, should i switch to DVI?

       

      I use 1600x900 res (native) at 32 bit

       

      Then to test whether all gradients look the same, i opened a new ps document and made a black to white gradient, but it was smooth, there were no bands in there. But when i made a simple white box, applied full gaussian blur, and zoomed in around 2000% i could see the gradual bands again though not as bad as in the colored psd. It seems the problem only happens when i give a glow, or blurs. Then i played Splinter Cell Conviction (everything Maxed out) and again  i could see gradient bands forming up in dark places, like when i die and a small cutscene is played, i could see gradient bands on the 4 corners. What could be the problem, is it the card? the lcd? i am new to lcd monitors so i dont know how to calibrate or whatever.

       

      Please check if anyone else can see the bands on their lcd?


        • 1. Re: Gradient banding in Samsung 20 inch LCD
          Noel Carboni Community Member

          Sounds like you're considering bad what most people think of as positive things about LCD displays:  Increased sharpness and increased ability to see small variations in brightness.  I take it you're moving up from a CRT monitor?

           

          Regarding banding, I don't know how sophisticated the games may be, but it's possible either the game or the video card you chose simply doesn't support "deep data" in the gaming environment.  Thus things like gradients are rendered as discrete transitions in an 8 bit environment.

           

          Why you're not seeing banding (aka posterization) in Photoshop gradients you make now may be that Photoshop is set to deliver a dithered gradient, meaning the gradient is salted with pixels of varying brightness to "hide" the posterization.  There's a checkbox for "Dither" at the top of the Photoshop main window when the gradient tool is selected.

           

          -Noel

           

           

          P.S., yes, I can easily see some minor posterization in the deep blue of the image you posted.

           

          P.P.S., you might consider working in 16 bits/channel mode to minimize the chances of seeing posterization, but keep in mind that if you make 8 bit products (e.g., JPEGs) out of your 16 bit documents you'll need to look them over critically for this kind of degradation.

          • 2. Re: Gradient banding in Samsung 20 inch LCD
            NinBuu Community Member

            yeah i am moving up from a crt monitor.

            Um but, i thought that my card supports HDMI output, and has been reviewed as quiet good for photo editing softwares.

             

            I am not used to working with 16 bit mode

             

            and after you said that, i checked a b/w gradient with and without dither, but i am getting posterization(bands) in both of them

            • 3. Re: Gradient banding in Samsung 20 inch LCD
              Noel Carboni Community Member

              It's not unreasonable that you should be able to see posterization - modern monitors have such large brightness ranges that the 256 levels of display brightness that are possible with 8 bit processing somewhere in the output pipeline can easily be seen.  Rest assured that with 16 bit data in the image it's not really happening because of the image data itself.  You can verify this by doing a Curves operation on a 16 bit image, pulling up or down on the curves, and observing whether the edges of the bands actually move.  If they do move, the image data isn't the cause, but something in the display pipeline is 8 bit.  This is state of the art at the moment and quite common.

               

              In short, if you're seeing posterization with 16 bit data, and you find it disturbing, then it's possible you find yourself in the growing company of people looking for higher bit depth monitor operation (e.g., what are commonly referred to as "10 bit display" systems).  Between Windows and Photoshop and display hardware and drivers, not everything is quite there yet.

               

              Do you have Windows set for 32 bit color?  Have you checked for updated display drivers (I know it's new, but...)?

               

              -Noel

              • 4. Re: Gradient banding in Samsung 20 inch LCD
                NinBuu Community Member

                hey noel sorry for the late reply, it was late at night and i had to sleep,

                 

                Yeah i set up windows 7 to highest 32 bit and i just checked my windows is up to date. I also downloaded the latest nvidia card drivers from the site.

                so you mean to say that i will have to put up with the posterization?

                 

                Hey man, i think i saw the display in pure darkness at night and was frustated at the bands showing up in color non existent area, but today morning when i studied it again, due to the room being bright i see less bands, and when i changed the channel to 16 bit they completely vanished, no problem except its taking a toll on my pc,

                 

                do you think upgrading to cs4 will change anything? thanks for the assist.

                 

                 

                P.S. I think i can put upwith a little banding in daytime, but it will bea huge problem when i work at night. And if you are suggesting 16 bits channel, then please tell me how to save for web display and print display

                • 5. Re: Gradient banding in Samsung 20 inch LCD
                  NinBuu Community Member

                  Hey Noel, I think i finally got the hang of it why i am seeing bands. I think its because of oversaturation in lcd monitors. Do you have any idea how to manage the oversaturation in an lcd monitor or do i have to buy some monitor calibration software?

                  • 6. Re: Gradient banding in Samsung 20 inch LCD
                    Noel Carboni Community Member

                    "Oversaturation in LCD monitors" is an overgeneralization.  What you're talking about has more to do with the color gamut of a particular monitor.

                     

                    If you have a wide gamut monitor, you can bring the color saturation of your images under control in color-managed apps only - e.g., Photoshop - through the use of a hardware calibrator.   I'm not sure how this is going to affect the visibility of posterization on your system though; I simply can't say by personal experience as my monitors are sRGB gamut.  I can say that you can expect to see MUCH more on a good LCD monitor than on even the best CRT monitor.  It's like night and day.

                     

                    Your best bet is to do research around your specific monitor and video card to find out if there's any way to configure/connect the hardware you have to give you deeper (10 bit) color.  I was reading a bit more on the subject and it's not clear what is the best way to accomplish that with a given system.  As I mentioned, you're on the cutting edge.

                     

                    -Noel

                    • 7. Re: Gradient banding in Samsung 20 inch LCD
                      NinBuu Community Member

                      i reduced contrast to around 60 (max 100) and increased sharpness to 100 because i was seeing really coarse text (idk why), I dont know if its wide-gamut or not, how do i check it? Its kind of a good but cheap monitor (Samsung Myst Eco B2030) costing around 150 USD. Now the text doesnt looks quite as coarse as it used to. I also reduced an option called "Coarse" to around 1800 (range 1700-1900) and increased fine to 100. Somehow even at night the posterization reduced. Now i dont see as many patches as yesterday.

                       

                      More on the matter is that i am not yet a proffesional graphic artist so i am not into buying any calibrating hardware. And the oversaturation problem still persist. I tried different color gamut's through color management in windows 7 but alas, the system default (sRGB IEC61966-2.1) looks the best, or it looks best because i am used to it.

                      The reason why i am talking about oversharp look is because whenever i see an image on web or photoshop or any other application, I can see sharp edges which i really think are worst thing for a designer. I dont want to make my eyes get used to sharp edges and produce graphics with that perception.

                       

                      If you are talking about a hardware calibrator : 1) I never used it and heard the first time from you (then searched it on google) 2) I dont think they are available in my area.

                       

                      I just want a simple fine look here, but no matter what things i try i am only getting coarse effect. Should i try switching to DVI?

                      Thanks for assist

                       

                      Message was edited by: NinBuu

                      • 8. Re: Gradient banding in Samsung 20 inch LCD
                        Noel Carboni Community Member

                        Regarding calibrating your display, it's not strictly necessary, but you did mention "oversaturation" in a post above.  It's certainly your call whether you want to make your color-managed applications put out calibrated color.

                         

                        Re switching to DVI, that's falling out of favor...  How are you currently cabled to your monitor?  HDMI?  VGA?  You've mentioned both.  DVI would CERTAINLY be better than VGA.

                         

                        This "Coarse effect" you speak of...  Are you talking about jaggy fonts, or what?  If so, do you have Font Smoothing enabled?

                         

                        When I first switched from CRTs to LCDs (in 2004) I marveled that most graphics created by people using CRTs were actually butt ugly, simply because they could not see the actual image content very clearly and tended to overlook things and overcompensate for their own monitors' shortcomings.

                         

                        On a good LCD using a good interface (DVI or better) you can see every pixel as a discreet element.  That's a given.

                         

                        After my switch from CRT to LCD I had to reset my perceptions - I had thoughts just like yours!  After a while you start to realize that what may look oversharp and harsh to you may even still be too subtle for CRT users.  For some time there's been a mix of CRTs and LCDs in the world, though honestly lately I've started to ignore the former as they are truly a dying breed (just try to buy a new CRT monitor nowadays).  It is not wrong to concentrate solely on making graphics look good on ultra sharp LCD monitors.  Don't be too hard on yourself for what you've produced in the past, when you couldn't "see clearly" yet. 

                         

                        That said, I should note that there are some LCDs that are not sharp at all.  From time to time people post on this forum that they have trouble seeing the Photoshop UI elements at their fixed small size, and as you're no doubt aware now with your monitor there's really no problem seeing them on a very sharp display.

                         

                        You could try taking a macro photo of what you're seeing on your display that you don't like.  Other than that it's very difficult to communicate about such issues on a forum.

                         

                        -Noel

                        • 9. Re: Gradient banding in Samsung 20 inch LCD
                          NinBuu Community Member

                          yeah i have font smoothing aka cleartype font is on.

                          I know what you are talking about but i am seeing too much clearly, all images are so saturated that i can see bright areas too bright with gradual bands. And yeah the text jagged and seperated with pixels. I think its not the fault of smoothing but the over sharpness and over saturation i was talking about. Take for example, type something in photoshop and sharpen it like hell. wait i can show you that.

                          Untitled-1.jpg

                          Well not as much like this coz i cant differentiate much between oversharpness and regular, but i applied sharpen four times here.

                          One more thing i noticed is that, when i squint my eyes all text are looking jagged at round corners and sharp edges, like midline in 'e' or round 'g'.

                          And another interesting thing i saw was that, i can see red pixels where the text was jagged. Like someone gave it a red glow. a pixelated red glow. And its really irritating.

                           

                          I cant take a macro shot coz i dont have a good cam. I am using VGA right now. So you are saying if i switch to DVI i am going to see more clear pixels than right now?

                           

                          Idk if this is related or not, but the ingame text is absolutely perfect, even the graphics are perfect.

                          • 10. Re: Gradient banding in Samsung 20 inch LCD
                            Chris Cox Adobe Employee

                            Yes, DVI would be clearer.

                            VGA may be going through a low quality DAC - causing banding.

                            HDMI - who knows.

                             

                            Get a good quality signal to the dispaly, then we can look at other color problems.