Page 1 of 1

instant mode and AMA

Posted: 28 Sep 2016, 16:57
by knypol
I just bought Benq 2411z and I have few questions:

1) Do i always need to change AMA after every reboot of the computer to achieve best ghosting reduction? Im not touching any osd settings just rebooting the PC. If i wont switch AMA i clearly see more ghosting in UFO test.
2) Is it normal that with Instant mode ON there is a little bit more ghosting than with OFF?
3) When i watch UFO test time to time there is litlle stutter (browser losing sync and i have everything closed except that one page). Is that mean i have some wrong settings?

For now with Instant mode ON im using:
strobe duty 10
strobe phase 50

ps. Im using 100Hz refresh rate and I did VT 1502 with CRU

Re: instant mode and AMA

Posted: 28 Sep 2016, 17:38
by Falkentyne
Instant mode ONLY deals with signal processing acceleration. Always leave it enabled.

I have the XL2720Z, so I can't see any ghosting improvement from disabling instant mode. Maybe you can, and I am not surprised if there is improvement. The 27" panels handle ghosting differently than the 24" panels, and tend to have more ghosting, but also have more contrast, and the gamma doesn't "degrade" at higher refresh rates. For one thing, 3d vision 2 has far more crosstalk on the XL2720Z than it does on the XL2411Z.

Disabling it improves some sort of rendering with video. I'm guessing it has something to do with dithering. It has absolutely no effect on game quality except making the input lag noticeably higher. If you really want to see how bad disabling instant mode is, set the refresh rate to 60hz THEN disable instant mode. Lag city.

If you're talking about the AMA "bugs", those are different and there are two different AMA "bugs" you can use.
One with blur reduction on.
One with a PROFILE SWITCH regarding blur reduction disabled. (this actually is a "workaround" to get the blur reduction AMA improvement to work with blur reduction disabled, there's no other way to do it).

The blur reduction on AMA improvement is brainless and easy:
1) Set blur reduction on.
2) Go to AMA and move the slider to off/premium then back to "high". Done.

ANY change to monitor BRIGHTNESS, any change to refresh rate, resolution (unless it's GPU scaled and the monitor doesn't refresh), any changes to the Service Menu Strobe settings (any of them) will revert the AMA to "high default" instantly.

The AMA improvement for blur reduction OFF is easy to do but hard to understand at first.
First you do the "blur reduction on" AMA toggle.

THEN you switch into a PRESET PICTURE MODE that has blur reduction DISABLED.
With blur reduction off, you can change brightness and the strobe settings without reverting the AMA. You still can't change refresh rate or resolution, though.

Turning blur reduction off manually does NOT work--the AMA gets instantly reset if you use the OSD to turn blur reduction off. You have to use profile switching instead.

This "bug" works because, when you change picture modes (in picture->advanced), when blur reduction is "on", and you change into a picture mode that has blur reduction "off" in the saved preset, the AMA is not recalibrated for blur reduction "off" due to a (lucky) firmware bug. So the blur reduction on improvement you did gets applied without being reverted.

I hope you can understand this. I have no way to explain it any easier :(

TestUFO having sync errors is just normal web/html stuff. Anything that causes CPU/video card usage can cause this. Not an issue with your monitor.

Re: instant mode and AMA

Posted: 28 Sep 2016, 18:38
by knypol
Falkentyne wrote:Hi,

The blur reduction on AMA improvement is brainless and easy:
1) Set blur reduction on.
2) Go to AMA and move the slider to off/premium then back to "high". Done.

I set blur reduction to ON and then swith slider off/high and everything is OK. I can clearly see much of the improvement in the matter of ghosting. But when i reboot (or just first boot up) my PC i need to swith the slider again from high to off to high to make that improvement ok. Im just wondering if this is normal and i have to do it every time. I dont make any changes to resolution, osd, brightness etc.

What is that 3d vision u mentioned?

Re: instant mode and AMA

Posted: 28 Sep 2016, 18:48
by Falkentyne
Rebooting changes the resolution. Your monitor is in 640x480 in BIOS. Or 60hz. Or 800x600 or something.
Remember I said ANY resolution change (that is not GPU scaling a different resolution at the same refresh rate) refreshes the monitor.

3d vision thing is Masterotaku finding a way to make GSYNC And ULMB blur reduction work at the same time on 1440p Gsync panels that have 3d vision 2 support. Doesn't apply to this monitor.

Re: instant mode and AMA

Posted: 28 Sep 2016, 23:07
by knypol
I read that my monitor can also work with lightboost. Is it better than Benq MBR - less crosstalks? Is that true that LB doesnt work with every application - only works with those installed in progra files?

Re: instant mode and AMA

Posted: 29 Sep 2016, 00:00
by Falkentyne
Lightboost has identical crosstalk (pixel for pixel position) as Benq Blur Reduction with VT 1500 (VT 1497-VT 1502).
VT tweak (1497-1502) works because of a bug in the firmware regarding Lightboost (the scalar uses this range internally, I tested it pixel for pixel. That's why the scalar internal resolution at VT 1497-VT 1502 is reported as 1280x1440).

The only reason to use lightboost is if you want less ghosting, but Lightboost will have 2.1ms lowest pixel persistence at 100hz and 1.4ms at 120hz (LB=10%). BBR can go down to 0.5ms before it gets too difficult to use. Also on the 24" monitors, Lightboost will raise the color temp to over 11000K, and the contrast will drop below 400:1. The 27" monitors can keep a 900:1 contrast ratio and reasonable color temp, but the overdrive ghosting is much worse on the 27" monitors. If you do the AMA "Low" toggle trick you already know about, there's absolutely zero reason to use Lightboost unless you want to use 3d glasses, the LB inverse ghosting on the 24" monitors is only slightly less than your "toggled" AMA (low), but the colors and contrast are much worse.

Re: instant mode and AMA

Posted: 29 Sep 2016, 07:29
by knypol
Thx for answers. After some testings with MBR ON i decided to leave it OFF. I switched to 144Hz without MBR and did Yours trick with AMA and MBR OFF. It works but...again... do I always need to go whole procedure after every reboot of the PC? In short:
1) turn on PC
2) pick picture mode Gamer2 (mbr on + ama high)
3) go to picture settings and toogle AMA
4) pick picture mode Gamer1 (mbr of + ama high)

I cannot imagine doing this every sad Benq implemented overdrive and basically without doing "the trick" its unusable - overshoots are so huge.

Re: instant mode and AMA

Posted: 29 Sep 2016, 12:41
by Falkentyne
Yes you have to do that, unfortunately.

The AMA mode is undocumented. Benq intended these monitors for gaming and low input lag. I asked them why didn't they document it. They said that the lighter overdrive has more input lag. (even if it's just 2 ms...its still "more"). And in FPS gaming at 144hz without blur reduction, you don't really notice the inverse ghosting. It's on the desktop that you usually notice it.

And yes they should have at least made more AMA steps. Masterotaku was the first one to bring that up over here. That's probably why we can even do this now to begin with. In V002 firmware, this wasn't possible. Setting AMA to high after enabling blur reduction in V002 firmware just made the AMA even higher, with even more inverse ghosting...