Blur Busters Forums

Hi blur busters,

I've experienced this issue while MBR is enabled on my recently bought MSI MAG271CQR. When MBR is switched on, then whenever I dart my eyes around the screen, there'll be a very brief bright red ghosting afterimage trailing behind objects. This is most noticable on white objects against a dark background. Needless to say, this is very jarring, because the things shown on screen may not be red by themselves, but they generate momentary red shadows.

This is not a one-off, I've actually also experienced the same on a monitor sold by a local reseller brand from my country (https://prismplus.sg/products/prism-f270i-pro - they probably rebrand OEM monitors sourced from China). I ended up returning that one for this same reason.

Before that, I was using a BenQ XL2411, and it did not exhibit this problem. Maybe the most obvious difference amongst these 3 monitors can be best described by comparing how they appear on https://www.testufo.com/blurtrail (default settings) when MBR is switched on, and when eye-tracking the moving white line.

BenQ XL2411 (TN, 1080p, 144Hz): a clear but faint 2nd white line appears a few pixels before the 1st white line. no other colors besides black and white are observed (this is as good as it gets)
MSI MAG271CQR (VA, 1440p, 144Hz): The line looks more like its ~6px long instead of 1px. It looks like a cyan-ish white, while the black in front and behind it is more like a reddish black. (There's also a 2nd faint cyan-ish line, FWIW)
Prism+ F270i Pro (local reseller brand, IPS, 1440p, 144Hz): Like the MAC271CQR, but even more pronounced. I recall feeling as if I was looking at 3~4 cyan and red (2 each) ~6px rectangles.

I've resigned to disabling MBR on my MAG271CQR for now, as I don't want to see a rainbow flash everytime I move my eyes.The XL2411 seems to get things right, so I wonder, what's the reason this "color separation" happens on the other 2 monitors? Is this something that is common with many implementations of MBR? Is there a name for this effect?

Do you have a 960fps high speed video camera? One of those smartphones listed at bottom of www.blurbusters.com/scanout

I'd like you to film the red flash at a minimum of 960 frames per second, then I'll be better able to explain why it's happening. I am not even sure if it's firmware-based or a GtG difference with red, or backlight based, so I would like to see this in action.

Wow, I definitely did not realize I had access to a high-speed video camera! Borrowed a Galaxy 9+, pointed its Super Slowmo camera mode at my screen while MBR was switched on, and the true nature of the monitor gets revealed:

https://youtu.be/d6FG1VQ7LOQ

I recorded 4 8-second takes of https://www.testufo.com/blurtrail:

Take 1: MBR OFF, moving edge. (control for the test, everything looks well-behaved and normal)
Take 2: MBR on, moving edge (look at all that red!)
Take 3: MBR on, with 1px lines (it seems I can't capture the lines actually turning red in this take, maybe lines are too thin? EDIT: after looking at the video again, I notice that the white mouse cursor and 1px lines "disappear" when the frame counter is red - I guess the red is not as bright as the white, and won't be captured if the object area is not big enough)
Take 4: MBR on, with 16px lines

Honestly I'm quite relieved that I wasn't crazy and seeing things, the red ghosting is real. I guess it's nothing to do with GtG response, and is probably due to firmware or their strobing implementation? (Any chance its graphics card drivers and/or how the card and the monitor are talking through DisplayPort? Though this sounds like a long shot) And any idea if this defect would be fixable on my monitor?

sneakertack, check out my review of the XG270QG at 13:07:
https://youtu.be/aNDCK6PiChY?t=788

Most of the wide gamut panels use a red phosphor that gets repeatedly excited during strobing by the backlight. LG, smartly, doesn't even offer blur reduction on their wide-gamut panels because they know it won't look good.

I often wonder if the engineers at the other companies even look at their screens...

sneakertack wrote: ↑

27 Jan 2020, 05:26

Honestly I'm quite relieved that I wasn't crazy and seeing things, the red ghosting is real. I guess it's nothing to do with GtG response, and is probably due to firmware or their strobing implementation? (Any chance its graphics card drivers and/or how the card and the monitor are talking through DisplayPort? Though this sounds like a long shot) And any idea if this defect would be fixable on my monitor?

That definitely is very weird.

No, it won't have anything to do with graphics card or graphics card driver. It's definitely something happening within the monitor.

Ashun wrote: ↑

30 Jan 2020, 22:13

sneakertack, check out my review of the XG270QG at 13:07:
https://youtu.be/aNDCK6PiChY?t=788

Most of the wide gamut panels use a red phosphor that gets repeatedly excited during strobing by the backlight. LG, smartly, doesn't even offer blur reduction on their wide-gamut panels because they know it won't look good.

Very interesting! Perhaps this is the cause

Ashun 1st time watching, new fan! Thank you for producing such a detailed review, and digging into why the red ghosting occured on your XG270QG. Your explanation cleared things up for me! So it seems like there are at least a few monitor models on the market where the red subpixels are photoluminescent (with a decay) which effectively makes MBR unuseable. But to my knowledge the MAG271CQR isn't wide-gamut? So it may not be limited to wide-gamut models? (basing it off the fact that it doesn't have HDR - but I'm a color noob and may be wrong though)

Initially I was frustrated that this defect didn't get reported in the RTINGS review, but thinking about it I can imagine why it didn't - the graphic they use to test BFI (their logo) is entirely red, slight red ghosting would not look out of place. To catch this, they'd be better served by a white-on-black test subject.

Looking at Ashun's red phosphur rise and decay graphs, I've now also concluded that when shopping for my next monitor, I should look for a strobing graph that's fully rectangular (no diagonal rising on the peak, no diagonal decay on the trough, trough should be zero), because that diagonal portion could be one subcolor photoluminescing.

We've personally reported this happening with the Viewsonic XG270QG and the MSI MAG271CQR (and a local rebranded monitor), but looking at the MAG271CQR's suggested alternatives on RTINGS, it seems there's a chance the MSI MPG27CQ and Gigabyte AD27QD could exhibit this defect as well. (maybe there's more, I only checked a few)

Chief I feel like this issue needs more awareness somehow. I wonder how many people might be trying MBR for the 1st time on one of these monitors, getting eyestrained / jarred by the color artifacts, and therefore wrongly concluding "I guess I'm one of those people who's susceptible to flicker, I should never switch on MBR again".

It looks like all of MSI's Optix line is advertised as having 115% sRGB coverage, so while not HDR, they do have the extended gamut.

You're right about people potentially being off-put by this. Most sites that review monitors don't seem to spend much time on backlight strobing. LG, Samsung, AUO, etc. probably need to give the monitor makers better guidance about when and when not to allow strobing.

I have an MSI MPG341CQR and it also exhibit this problem. It's way too late for me to return it and I'm a bit angry about this. I realized the importance of strobing too late I thought 4ms response time would eliminate most of the blur anyway, only then I realized how sample-and-hold displays really work at lower framerates.
That's when I experimented with the "Anti Motionblur" mode more and noticed the red and teal ghosting who not only looks awful by themselves but the worst thing about them is how the "red ghost" can create blobs of unnaturally bright spots inside objects, WHILE the "blue/teal ghost" create dark spots inside other objects. It's honestly pretty bad although not visible all the time, when it does happens the image is ruined.

This is with native single strobe FPS (which doesn't even go lower than 75hz, this is another BS I wasn't aware about at all!!)
The somewhat good news is that double/triple strobe really reduce the bad effects but this shows double or triple images. So 72 FPS at 144hz strobing, or 60FPS with 120hz strobing. I noticed setting the FPS to x1.5 of the refresh rate (ie 96FPS at 144hz strobing) shows the best quality with the bad ghosting diseapearing almost entirely and the image staying very clean with barely noticeable image doubling, at the cost of very minimal motion judder. Unlocked framerates over 80FPS with 144hz strobe in general looks pretty good. But yeah, judder and triple image isn't optimal and I can't reach those framerates everywhere.
But I also heard actual CRTs does this anyway so, what do you think? Is this usable to you guys?

Still, I'm having an hard time coping with this, even if there was no way for me to avoid it, it's not like monitors reviewer do their job correctly (save for Ashun I guess) so I wouldn't have known either ways, and from what I know there's no ultrawide with those specs and speed with a good BFI mode, the LG one being stuck to 144hz strobing apparently.
My brother had an LCD monitor with a great 60hz strobing mode for more than a decade now and I can't believe I get something worse on a 900$ monitor in 2020 :/

Since I'm going to keep the thing anyway, what do you guys suggest I do?
1) just forget about MBR and deal with the blur
2) use MBR with non native Hz strobe despite the double/triple image and motion judder
3) sell it and get that sweet, non existent 1440p144hz ultrawide monitor with perfect strobing features