Asus VG248QE or BenQ XL2411Z for use with Lightboost/MBR?

[kapit0]

Just returned my Acer GN246HL as I found the inverse-ghosting really annoying and found it had a weird scanline effect during vertical movement with lightboost enabled.

Out of the Asus VG248QE and BenQ XL2411Z, which would you guys recommend for use with backlight strobing?

Side-question: I know the BenQ has slightly less customisable overdrive settings (responsible for inverse-ghosting). How noticable would the ghosting be with MBR?

[masterotaku]

Just returned my Acer GN246HL as I found the inverse-ghosting really annoying and found it had a weird scanline effect during vertical movement with lightboost enabled.

That will be key for my following opinion.

Out of the Asus VG248QE and BenQ XL2411Z, which would you guys recommend for use with backlight strobing?

I would normally recommend the BenQ because its motion blur reduction method can be used at any refresh rate >=50Hz. Perfect for 60fps capped games, or when you can't maintain very high fps (you can also control the strobe length a lot, removing a lot more motion blur than Lightboost). It works with any custom resolution even at fractional Hz, like 62.5Hz or things like that. The Asus however only has Lightboost between 100Hz and 120Hz.

Buuut....

The BenQ has a lot more overdrive artifacts (source: owners of both monitors, not me), and I think I've heard that your Acer monitor is a worse, but I don't know how much. The Asus is basically perfect in motion.

Still, the BenQ can also use Lightboost instead of motion blur reduction, where the overdrive mode is totally different. It isn't as perfect as the Asus, but still pretty good regarding overdrive artifacts.

Side-question: I know the BenQ has slightly less customisable overdrive settings (responsible for inverse-ghosting). How noticable would the ghosting be with MBR?

There is a hidden setting with firmwares V4 and up, which requires simply toggling the overdrive setting. That way it will be less strong. But it will still be stronger than I'd like.

Another hidden setting is using Lighboost and then going back to the normal MBR mode. At best conditions, it will look like this is you lower contrast a lot:



But it has bad artifacting if you use normal contrast levels.

What you can expect with MBR and the toggling trick is this:



This last screenshot may be a bit better than what you'll see in real life :p.


So your choice is: freedom of blur reduction vs almost zero overdrive artifacts.

[Falkentyne]

Inverse ghosting and overdrive artifacts are a byproduct of LCD tech and can't really be avoided. Pixels need time to transition from one color to another and reset back, and depending on the color it starts at and ends, each transition takes a different amount of time. At best case, you can do a transition in 2ms (usually one shade of grey to another shade of grey), and at worst case, around 18ms. Also screens refresh top to bottom, thus the bottom will have more "input lag" than the top. When you wind up combining these two, with backlight strobing (blur reduction), then you get crosstalk (the next frame's pixel data being merged with the current frame), and the higher the refresh rate, the worse the crosstalk, since the frame time is lower(120hz = 8.3ms response time, vs 60hz=16.7ms response time. now if you have an 18ms color transition at 120hz (8.3ms frame), you can see how bad the crosstalk can be, compared to 60hz (16.7ms frame with 18ms max color transition).

The scanline effect you see with lightboost is a byproduct of a longer blanking interval being used to help greatly reduce crosstalk. If you use XL2411Z WITHOUT a vertical total tweak, for instance and enable blur reduction, you won't have any scanlines, but you will have LOTS of crosstalk. If you use a VT tweak, which accomplishes the same thing that Lightboost does internally, lower crosstalk, but might have scanlines.

All that being said, the Asus VG248QE in Lightboost mode, at 100hz (Only at 100hz) has the LOWEST amount of overdrive ghosting artifacts of any blur reduction monitor tech currently out, that's not a CRT. While it's not 100% perfect, to get extremely good results, the monitor must be warmed up for 1 hour, then after you enable Lightboost mode, go into the Asus service menu and change Overdrive gain (OD Gain) from 0F to 0C. This will reduce the faint inverse ghosting around the bottom of the screen and make it close to invisible, while barely affecting the top of the screen in a bad way (a very slight amount of normal ghosting will be added by the lowering of the OD gain, but it looks awesome. And in games, you will see NO artifacts at all).

The problem?
1) you're limited to 100hz if you want this clarity (Lightboost at 110hz looks very butt ugly for some reason; this also applies to the same Lightboost refresh rate on the Benq monitors), and Lightboost at 120hz will have more inverse ghosting. You can't use Lightboost at custom refresh rates like 60hz or 80hz or 91hz or 85hz like you can with Benq blur reduction via VT tweaks and custom resolutions. (technically, you CAN use 60hz lightboost, by creating a custom resolution and using a VT of 1155-1180 (this depends on the firmware and model, but basically only certain values of VT for lightboost activation were "checked" for valid range) but it's double strobed using 120hz rates, and looks as bad as 60hz Benq blur reduction with "Single strobe=OFF")

2) the BIG problem with Lightboost--the contrast ratio. The monitors that have a 900-1000:1 contrast ratio drop down to lower than 350:1 in Lightboost mode (VG248QE), AND in addition to that, the color temperature rises to over 11,000K, and the monitors that keep a 900:1 contrast ratio in Lightboost mode--only the 27" 1080p TN monitors can do that (Benq XL2720Z, Benq XL2720T, Asus VG278H) have FAR worse inverse ghosting than the 24" monitors due to the higher contrast.

The Lightboost bad contrast and the extremely blue LB color temp is why many people moved on from the good old VG248QE. It was one of the first, though, and still a decent entry level monitor if you get it cheap.

[kapit0]

Thanks for your replies!

Another hidden setting is using Lighboost and then going back to the normal MBR mode. At best conditions, it will look like this is you lower contrast a lot:

What do you mean by this? If I use Lightboost and then go back to the BenQ's MBR, why is this different from just using MBR?

I'm thinking more about going for the BenQ now. It's on offer right now for £199 at my local Maplin (as opposed to the Asus for £279, lol). The inverse ghosting is barely noticable at all in this photo though, so if I can really get it looking like that, I'd be fine using it

[kapit0]

Also, I saw someone complaining that their XL2411Z looks like this: http://www.overclock.net/t/1505130/ligh ... id/2118605

Does it actually look like this or did he do something wrong? I'd much rather spend more on the Asus if it means no inverse-ghosting.

Thanks again in advance.

[masterotaku]

What do you mean by this? If I use Lightboost and then go back to the BenQ's MBR, why is this different from just using MBR?

Yes, it's different. As for why, I think it's because it's trying to apply the Lightboost overdrive to MBR or something like that.

The inverse ghosting is barely noticable at all in this photo though, so if I can really get it looking like that, I'd be fine using it

Best case scenario, remember. With normal (40) contrast, there will be some very fucked up color transitions, mostly with bright elements and backgrounds. It's pretty good with very low contrast, however. But you probably won't like using that. So I recommend this secret overdrive mode for dark games.

Does it actually look like this or did he do something wrong?

It looks like that when you don't toggle the overdrive setting (which you have to do after every resolution change, refresh rate change, and every time you turn on your monitor). The toggled setting is a bit better, but not a lot.

It's the only complaint I have about that monitor, and with that price difference, certainly go for it .

[kapit0]

Hmm...it's a tough decision. I can get the Asus for £210 on Amazon, and if it means a clearer image with Lightboost I think I'd be happier spending the extra.

How does the BenQ look with the VT tweak (apparently it allows more time for the pixels to switch colour)?

Sorry for the questions After the hassle of returning my old Acer I don't want to need to do it again.

[masterotaku]

How does the BenQ look with the VT tweak (apparently it allows more time for the pixels to switch colour)?

It doesn't affect overdrive artifacts. What it does is reduce crosstalk in the screen (by default there is a lot of it), to make it very similar to Lightboost (which does something like that automatically). With MBR, you can control where you want to place the crosstalk zone.

And I repeat, the BenQ has Lightboost available too (you have to unlock it with different methods than the Asus). Just not as perfect as the Asus, but still with low overdrive artifacts compared to MBR.

[kapit0]

Alright. I'll do some thinking about it. Thanks for your help!