"Color Burn" (Or maybe "Dodge") effect when strafing @240Hz?

[layla]

Hi All,

I'm a new member here, but have been reading some of the material for quite a while, and also am a ZisWorks x39 owner

On a 240Hz 1080p TN display with pixel overdrive enabled, I'm noticing what looks to be similar to "color-burn" or "dodge" of intense colors under strafing motion (e.g. image a poster on a wall, and strafing side to side while facing the wall - the poster looks normal at rest, and then appears to have a "color burn" applied to it under motion. It returns to it's normal (correct) appearance again at rest).

Has anyone else ever observed this kind of phenomenon? I'm going to do more tests later today and try to determine whether it's panel-related/panel-specific, or a generic artifact. And moreover, try to determine whether something we're doing in our engine is causing the issue, or whether again, it's a panel issue (or an optics issue - though I'm inclined to doubt that)...

This is vsync@240Hz with no dropped frames.

Thanks in advance for any feedback, particularly anyone who might have insight!
Layla

P.S. For those interested in high refresh displays (probably everyone here) - heads up that we're quietly developing a game/graphics engine which is already capable of driving 4K@1500Hz+ in complex interactive scenes today (unfortunately no displays actually support displaying this many pixels this fast, of course) - but hopefully one day we can help be a driving force in creation and adoption of actual 1KHz+ displays...

[lexlazootin]

Nice, a ZisWorks x39 owner! i'm really curious how many of them Zis sold.

The color 'burn' you might be talking about is probably simple pixel response. When pixels change from one color to another they have to physically change. This process can take anywhere between 2-10ms depending on the panel, the technology (IPS/TN) and how big the change. In the OSD sometimes called Overdrive or whatever the manufacture wants to call it tries to speed up this process essentially pumping more voltage through it but it can cause overshoot and a inverse ghosting.

www.testufo.com/ghosting

That link will send you to a test that was purposefully built to cause overshoot and show off your panels flaws.

[layla]

... called Overdrive or whatever the manufacture wants to call it tries to speed up this process essentially pumping more voltage through it but it can cause overshoot and a inverse ghosting.

www.testufo.com/ghosting

That link will send you to a test that was purposefully built to cause overshoot and show off your panels flaws.

Thanks for the quick response! That makes perfect sense, and the inverse ghosting is readily apparent on that particular test - and fully gone as soon as I set the panel OD back to "normal".

That's quite frustrating however, because I'm sure lots of panel owners will not be aware of this limitation and may end up blaming the content...

P.S. Re: ZisWorks - tough to know, but extrapolating from the forums, I'd guess somewhere above 50 and less than 200? (As far as I know, he sold all of his kits, I'm just unsure of how many had )

[layla]

Also interesting, while the ghosting test was mostly clean after setting OD back to "normal", our engine content still displays some "color burn" at all settings.

At "OD Extreme" - dramatic color burn in our engine while strafing and marked inverse ghosting on the ghosting test
At "OD Normal" - most ghosting on the test is gone, but some minor color burn still remains in our engine
At "OD Disabled" - looks like normal (not inverse?) ghosting in the ghosting test, and some minor color burn visible in engine

"OD Normal" seems to be the best compromise, but again, I'm left dreaming of the day when we have better panel technology which doesn't suffer these kinds of artifacts. Our engine has almost no perceptible aliasing, which makes these panel artifacts particularly stick out like a sore thumb against otherwise very creamy smooth graphics I'm guessing OLED would do a lot better, but of course then you have to worry about actual panel burn of a very different variety

[RealNC]

The ovedrive setting exists exactly because of the compromises. If the highest setting looked good, there would be no reason to offer the setting in the first place. Monitors would ship with it set to maximum and not offer a configuration setting for it at all.

The vast majority of monitors offer a medium setting that reflects the best compromise between image quality and least amount of ghosting. The low setting is mostly useless on many monitors, except the fastest TN panels where "OD low" is still a very low pixel response time and thus you can maximize image quality at very little cost. The high setting gives you maybe 1-2ms (tops) lower pixel response but for a rather big degradation in image quality. So it's not that useful either. But it's there if 1-2ms are more important to you than image quality.

[layla]

The ovedrive setting exists exactly because of the compromises.

Naturally! A UI Setting would be worthless if it didn't offer some set of compromise or trade-off interesting to the user.

If the highest setting looked good, there would be no reason to offer the setting in the first place.

You should realize that this is not at all an obvious conclusion. It would be perfectly reasonable to assume, like I did, that the reason the setting existed was because while it lowered latency and also looked better (due to less motion blur) on overdrive, it would also shorten the life of your panel and/or void your warranty. I was wrong in my assumption, but it was not an unreasonable assumption for a person to make.