CRT Ghosting Sync Adjustment?
I have access to several CRT desktop monitors and a Sony VPH-G90 CRT projector.

After some initial issues with getting 3D Vision and Windows7 to get things running in the right resolutions and refresh rates, I find that all the displays have ghosting/separation issues at either the top or the bottom of the screen.

Changing refresh rates and resolutions does not seem to change the characteristics of the problem on any display. For example on the G90 the bottom 1/3rd of the screen is where it ghosts and that stays consistent regardless of the resolution and refresh rates I've tried - and is consistent across whatever application is running.

It seems like being able to adjust the sync time to the glasses a few ms up or down would probably mitigate the problem.

In other posts I've seen references to previous driver versions that allowed some sync adjustment. Is that true? If so, what versions had options and what were they?

As it stands I am not satisfied. The fact that the CRTs I have tried are all a little different in the way they perform underscores the need for individual adjustment options.
I have access to several CRT desktop monitors and a Sony VPH-G90 CRT projector.



After some initial issues with getting 3D Vision and Windows7 to get things running in the right resolutions and refresh rates, I find that all the displays have ghosting/separation issues at either the top or the bottom of the screen.



Changing refresh rates and resolutions does not seem to change the characteristics of the problem on any display. For example on the G90 the bottom 1/3rd of the screen is where it ghosts and that stays consistent regardless of the resolution and refresh rates I've tried - and is consistent across whatever application is running.



It seems like being able to adjust the sync time to the glasses a few ms up or down would probably mitigate the problem.



In other posts I've seen references to previous driver versions that allowed some sync adjustment. Is that true? If so, what versions had options and what were they?



As it stands I am not satisfied. The fact that the CRTs I have tried are all a little different in the way they perform underscores the need for individual adjustment options.

#1
Posted 02/02/2010 02:53 AM   
CRT's will always have ghosting problems due to an issue known as phosphor decay.

Radiation is shot from the rear of the monitor and hits pixels that are actually filled with phosphor. When green phosphor is charged the image takes longer to decay than red or blue and therefore it lingers on the screen which causes the ghosting as it hasn't fully faded before the shutter on the glasses opens on the other eye.

Also, the way you describe that only some of the image is ghosting is due to the way cathode ray tubes actually paint the image onto the screen. It starts at either to top or bottom and paints up or down. If you change the sync the ghosting will just appear at different parts of the screen.

There is nothing you can do the get around this issue, except invest in new hardware.

My suggestion for truly ghost free images are DLP projectors and rear projections TV's such as the new Optoma HD66 or Mitsubishis line of DLP rear projection tvs. LCD's still have slight ghosting due to pixel response times (substantially better than CRT).
CRT's will always have ghosting problems due to an issue known as phosphor decay.



Radiation is shot from the rear of the monitor and hits pixels that are actually filled with phosphor. When green phosphor is charged the image takes longer to decay than red or blue and therefore it lingers on the screen which causes the ghosting as it hasn't fully faded before the shutter on the glasses opens on the other eye.



Also, the way you describe that only some of the image is ghosting is due to the way cathode ray tubes actually paint the image onto the screen. It starts at either to top or bottom and paints up or down. If you change the sync the ghosting will just appear at different parts of the screen.



There is nothing you can do the get around this issue, except invest in new hardware.



My suggestion for truly ghost free images are DLP projectors and rear projections TV's such as the new Optoma HD66 or Mitsubishis line of DLP rear projection tvs. LCD's still have slight ghosting due to pixel response times (substantially better than CRT).

#2
Posted 02/02/2010 03:44 AM   
[quote name='mourt' post='993635' date='Feb 2 2010, 03:44 AM']CRT's will always have ghosting problems due to an issue known as phosphor decay.[/quote]
Nevertheless, it's totally possible that by adjusting the sync timing the situation could be improved. nVidia just have generic timing in there to try and work with as many screens as possible, but it's not tailored to individal screens, and all screens are slightly different. Since it used to be in the drivers it's something they can obviously easily do, so why not allow that extra control for hardcore users? (I think probably most people with 3D Vision [i]are [/i]hardcore users). It doesn't have to be in the control panel where noobs can mess things up, just some registry settings. Let us control the shutter period as well if the hardware allows that.

Come on nVidia, give us this sort of control and there's far more chance I'll be buying Fermi and sticking with 3D Vision in the future.
[quote name='mourt' post='993635' date='Feb 2 2010, 03:44 AM']CRT's will always have ghosting problems due to an issue known as phosphor decay.

Nevertheless, it's totally possible that by adjusting the sync timing the situation could be improved. nVidia just have generic timing in there to try and work with as many screens as possible, but it's not tailored to individal screens, and all screens are slightly different. Since it used to be in the drivers it's something they can obviously easily do, so why not allow that extra control for hardcore users? (I think probably most people with 3D Vision are hardcore users). It doesn't have to be in the control panel where noobs can mess things up, just some registry settings. Let us control the shutter period as well if the hardware allows that.



Come on nVidia, give us this sort of control and there's far more chance I'll be buying Fermi and sticking with 3D Vision in the future.

#3
Posted 02/02/2010 02:59 PM   
I have a Barco Graphics 808 runnning at 100hz and 120hz and seen the issue mentionned with both frequencies.

I don't think it is "ghosting" in the sense that everyone talk about it. It looks more like the images don't align at all.

As I understand ghosting is residual. We're talking here full fledge dual images.

I can live with some residual ghosts so to speak, but the dual images like KrisRobert is talking about are really difficult to deal with.
I have a Barco Graphics 808 runnning at 100hz and 120hz and seen the issue mentionned with both frequencies.



I don't think it is "ghosting" in the sense that everyone talk about it. It looks more like the images don't align at all.



As I understand ghosting is residual. We're talking here full fledge dual images.



I can live with some residual ghosts so to speak, but the dual images like KrisRobert is talking about are really difficult to deal with.

#4
Posted 02/03/2010 12:20 AM   
Yeah, before I got my 2233 I was running a 24inch CRT. The bottom of the screen, maybe 2 inches or so of it were completely ghosted. As in, those 2 inches looked the exact same as the screen looks without wearing glasses. Top of the screen had the least ghosting anywhere on the monitor. Timing adjustments would have allowed me to set the middle of the screen as the least ghosted area.
Yeah, before I got my 2233 I was running a 24inch CRT. The bottom of the screen, maybe 2 inches or so of it were completely ghosted. As in, those 2 inches looked the exact same as the screen looks without wearing glasses. Top of the screen had the least ghosting anywhere on the monitor. Timing adjustments would have allowed me to set the middle of the screen as the least ghosted area.

#5
Posted 02/03/2010 01:25 AM   
[quote name='sdumas' post='994237' date='Feb 3 2010, 12:20 AM']I don't think it is "ghosting" in the sense that everyone talk about it. It looks more like the images don't align at all.

As I understand ghosting is residual. We're talking here full fledge dual images.[/quote]The images aren't supposed to 'align' on screen, otherwise you get no 3D. It's the seperation that gives your brain the depth information. When you see a double image it means the left eye is seeing part of the image intended for the right eye, and vice versa. You'll see the double image is there even with one eye closed.

Ghosting is a good term for the effect because it is a ghost image, even though it's completely different to the motion blur type ghosting you get on LCDs. I think most people when using the term ghosting here know they're talking about stereo crosstalk.
[quote name='sdumas' post='994237' date='Feb 3 2010, 12:20 AM']I don't think it is "ghosting" in the sense that everyone talk about it. It looks more like the images don't align at all.



As I understand ghosting is residual. We're talking here full fledge dual images.The images aren't supposed to 'align' on screen, otherwise you get no 3D. It's the seperation that gives your brain the depth information. When you see a double image it means the left eye is seeing part of the image intended for the right eye, and vice versa. You'll see the double image is there even with one eye closed.



Ghosting is a good term for the effect because it is a ghost image, even though it's completely different to the motion blur type ghosting you get on LCDs. I think most people when using the term ghosting here know they're talking about stereo crosstalk.

#6
Posted 02/03/2010 04:06 PM   
[b]"The images aren't supposed to 'align' on screen, otherwise you get no 3D. It's the seperation that gives your brain the depth information. When you see a double image it means the left eye is seeing part of the image intended for the right eye, and vice versa. You'll see the double image is there even with one eye closed."[/b]

Thanks for the clarification, but I still have some questions.

I understand that the images are separated for left and right eyes. If you look without glasses, yes you will see dual images, but with the glasses on, they should be aligned making a seamless 3D image. I don't see two images when I look through the glasses with either eye (one at a time of course). But when I look with my two eyes through the glasses - it should be smooth - ei - one "virtual image". What I see is dramatic double images- center has a tendendy to be OK, but everything else is going bananas. If I increase depth to more than 10-12% it's literraly unwatchable. If there is no depth, what is the point of having 3D. My 126" screen might as well be in 2D.

The good news though is that the Nvidia demo logo in 3D is OK until about 20%.

Movies through the stereoscopic viewer (the real one - not the Nvidia bundled version) are very difficult to adjust (convergence) and almost unwatchable. Even the Rhine Valley movie is difficult to adjust. I either have to accept that convergence will be bad at the bottom or bad at the top. I tried to adjust convergence according to the words under the nice popping globe. If the text is right, the rest is not. If the main image is clear, I can't read the text. It's driving me nuts.

CODWarfare in 3D is also exhibiting similar behaviour.

I'll be playing with the different versions of drivers. It's a pain, because it takes quite a big amount of time to make sure that the CRT is detected properly, the numerous reboots required when removing drivers, re-installing driver - start the 3D wizard and pray that it will work this time - adjust resolution and frequency to get 100hz or 120hz and make sure that NVidia recognize the res... etc. etc. etc....

If anyone finds a magical solution - let us know!!!
"The images aren't supposed to 'align' on screen, otherwise you get no 3D. It's the seperation that gives your brain the depth information. When you see a double image it means the left eye is seeing part of the image intended for the right eye, and vice versa. You'll see the double image is there even with one eye closed."



Thanks for the clarification, but I still have some questions.



I understand that the images are separated for left and right eyes. If you look without glasses, yes you will see dual images, but with the glasses on, they should be aligned making a seamless 3D image. I don't see two images when I look through the glasses with either eye (one at a time of course). But when I look with my two eyes through the glasses - it should be smooth - ei - one "virtual image". What I see is dramatic double images- center has a tendendy to be OK, but everything else is going bananas. If I increase depth to more than 10-12% it's literraly unwatchable. If there is no depth, what is the point of having 3D. My 126" screen might as well be in 2D.



The good news though is that the Nvidia demo logo in 3D is OK until about 20%.



Movies through the stereoscopic viewer (the real one - not the Nvidia bundled version) are very difficult to adjust (convergence) and almost unwatchable. Even the Rhine Valley movie is difficult to adjust. I either have to accept that convergence will be bad at the bottom or bad at the top. I tried to adjust convergence according to the words under the nice popping globe. If the text is right, the rest is not. If the main image is clear, I can't read the text. It's driving me nuts.



CODWarfare in 3D is also exhibiting similar behaviour.



I'll be playing with the different versions of drivers. It's a pain, because it takes quite a big amount of time to make sure that the CRT is detected properly, the numerous reboots required when removing drivers, re-installing driver - start the 3D wizard and pray that it will work this time - adjust resolution and frequency to get 100hz or 120hz and make sure that NVidia recognize the res... etc. etc. etc....



If anyone finds a magical solution - let us know!!!

#7
Posted 02/03/2010 10:02 PM   
Thanks for the replies.

In the absence of any indication from NVidia that they will support timing adjustments for CRT, I see no option other than to return the kit.

Even if the end result was not perfect, if I was able to adjust it to improve the performance and optimize it for the displays I have I would certainly keep it.

As it is, it is unacceptable.
Thanks for the replies.



In the absence of any indication from NVidia that they will support timing adjustments for CRT, I see no option other than to return the kit.



Even if the end result was not perfect, if I was able to adjust it to improve the performance and optimize it for the displays I have I would certainly keep it.



As it is, it is unacceptable.

#8
Posted 02/05/2010 05:39 PM   
[quote name='mourt' post='993635' date='Feb 1 2010, 07:44 PM']My suggestion for truly ghost free images are DLP projectors and rear projections TV's such as the new Optoma HD66 or Mitsubishis line of DLP rear projection tvs. LCD's still have slight ghosting due to pixel response times (substantially better than CRT).[/quote]

Yeah, the HD66 looks nice. Inexpensive, bright, 120Hz. But, oh wait - its not supported... And if it is in a future driver release, is there any reasonable expectation that it will continue to be supported? I see lots of posts about people dissapointed when driver updates no longer detect their displays properly.

The 3DVision product states that it supports CRT displays capable of 100Hz or better - I have several and none work well enough to use.

The lack of response to overwhelming requests for adjustment options on supported sets and more open compatibilty in general makes spending money on a new set, keeping the 3D Vision kit, or investing in more glasses sound like a bad investment.
[quote name='mourt' post='993635' date='Feb 1 2010, 07:44 PM']My suggestion for truly ghost free images are DLP projectors and rear projections TV's such as the new Optoma HD66 or Mitsubishis line of DLP rear projection tvs. LCD's still have slight ghosting due to pixel response times (substantially better than CRT).



Yeah, the HD66 looks nice. Inexpensive, bright, 120Hz. But, oh wait - its not supported... And if it is in a future driver release, is there any reasonable expectation that it will continue to be supported? I see lots of posts about people dissapointed when driver updates no longer detect their displays properly.



The 3DVision product states that it supports CRT displays capable of 100Hz or better - I have several and none work well enough to use.



The lack of response to overwhelming requests for adjustment options on supported sets and more open compatibilty in general makes spending money on a new set, keeping the 3D Vision kit, or investing in more glasses sound like a bad investment.

#9
Posted 02/07/2010 06:11 PM   
[quote name='KrisRoberts' post='997088' date='Feb 7 2010, 07:11 PM']Yeah, the HD66 looks nice. Inexpensive, bright, 120Hz. But, oh wait - its not supported... And if it is in a future driver release, is there any reasonable expectation that it will continue to be supported? I see lots of posts about people dissapointed when driver updates no longer detect their displays properly.

The 3DVision product states that it supports CRT displays capable of 100Hz or better - I have several and none work well enough to use.

The lack of response to overwhelming requests for adjustment options on supported sets and more open compatibilty in general makes spending money on a new set, keeping the 3D Vision kit, or investing in more glasses sound like a bad investment.[/quote]


Well if you would like driver support for a DLP system the Mitsubishi TV's have been supported from day dot, and you could also look into the Acer H5360 which is supported. I'm pretty sure the Optoma will eventually be supported.. its not as if the hardware is incompatible, it still works in its currrent state.

I would never bet on CRT with stereoscopic viewing. As much as I love CRT and wish it was easily possible for 3d its just not really feasible, and while CRT is "compatible" with 3d Vision its not optimal. You may be dissapointed just as I was when my glasses arrived and tried them out on my 2070SB, but making the switch to DLP was truly worth every cent... for me.

Nvidia really should have a disclaimer on their webpage about CRT's and horrible ghosting and other issue though.
[quote name='KrisRoberts' post='997088' date='Feb 7 2010, 07:11 PM']Yeah, the HD66 looks nice. Inexpensive, bright, 120Hz. But, oh wait - its not supported... And if it is in a future driver release, is there any reasonable expectation that it will continue to be supported? I see lots of posts about people dissapointed when driver updates no longer detect their displays properly.



The 3DVision product states that it supports CRT displays capable of 100Hz or better - I have several and none work well enough to use.



The lack of response to overwhelming requests for adjustment options on supported sets and more open compatibilty in general makes spending money on a new set, keeping the 3D Vision kit, or investing in more glasses sound like a bad investment.





Well if you would like driver support for a DLP system the Mitsubishi TV's have been supported from day dot, and you could also look into the Acer H5360 which is supported. I'm pretty sure the Optoma will eventually be supported.. its not as if the hardware is incompatible, it still works in its currrent state.



I would never bet on CRT with stereoscopic viewing. As much as I love CRT and wish it was easily possible for 3d its just not really feasible, and while CRT is "compatible" with 3d Vision its not optimal. You may be dissapointed just as I was when my glasses arrived and tried them out on my 2070SB, but making the switch to DLP was truly worth every cent... for me.



Nvidia really should have a disclaimer on their webpage about CRT's and horrible ghosting and other issue though.

#10
Posted 02/08/2010 10:28 AM   
(THE TRICK TO REDUCE CRT GHOSTING!) The simple fix for those who can only afford a crt and the 3dvision kit is to simply (Run both the PC and the game brightness levels as high as possible). i also ran the max rez, 85 herts refresh rate, and set the nvidia preference too performance. these setting made a HUGE difference! the ghost image is barely noticeable now, where before games weren't worth playing with the heavy ghosting. now all the struggling game enthusiasts can enjoy decent 3d vision. ENJOY!
(THE TRICK TO REDUCE CRT GHOSTING!) The simple fix for those who can only afford a crt and the 3dvision kit is to simply (Run both the PC and the game brightness levels as high as possible). i also ran the max rez, 85 herts refresh rate, and set the nvidia preference too performance. these setting made a HUGE difference! the ghost image is barely noticeable now, where before games weren't worth playing with the heavy ghosting. now all the struggling game enthusiasts can enjoy decent 3d vision. ENJOY!

#11
Posted 02/15/2010 12:23 AM   
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