Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Many sites including LinusTechTips, RTINGS, TomsHardware, and others use the free Blur Busters pursuit camera invention. Now also avaialble as a rail-less smartphone wave, too!
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JDnoob
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Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by JDnoob » 07 Aug 2020, 13:03

Very brightly backlit VA LCD TVs with local dimming could be an excellent and practical way to achieve very low persistence blur (MPRT) for gaming while further achieving a very high contrast ratio and great overall picture quality. Some high end LCD TV's have a peak brightness of nearly 3000 nits! The primary driving force for these uber-bright backlights is undoubtedly HDR. But as a side effect of all this extra brightness, some of these TVs can achieve impressively low persistence blur via BFI. This is wonderful considering these displays also prioritize great picture quality, wide color gamuts, and have much higher contrast ratios than most ULMB or related monitors with TN/IPS panels and without local dimming. They are perfect for gamers looking for great motion performance and great dark room performance out of the same display. 60hz single-strobing also makes these TVs far superior for console gaming, emulation, content consumption (e.g. YouTube, Twitch), and PC games that are limited to 60hz or otherwise have difficulty running at higher frame rates (such as many AAA games).

Last year I bought a 65" 2018 Vizio P Series TV (P65-F1) with motion performance that impressed me enough to give pursuit photography a shot and post about it here. Below are some (no rail, amateur) pursuit photos with my iPhone 7. Although the production value is lower than ideal, it should hopefully be good enough to gauge the motion performance of this TV along with similar models. This model is advertised as having ~1000 nit backlight. I am very curious if brighter models such as the ~3000 nit P Series Quantum X could perform much better.

If anyone is interested, I will mention the settings I have used on the TV when I took the videos. Even though this is a 4k TV, all videos were shot with a signal resolution of 1920x1080 with 100% windows scaling at 120hz, 100hz, and 60hz respectively. The backlight of the TV during testing was set to 0 with "clear action" (BFI) obviously enabled. This appears to be a very usable brightness unless you are in a brighter room. With BFI enabled, backlight is fully adjustable between 0-100 and is inversely proportional with motion clarity. This implies that the backlight setting is adjusting pulse width so the TV is always reducing the maximum amount of motion blur possible at any given brightness. At backlight 0, the brightness is ~100 nits. At backlight 100, the TV is over twice as bright but also with over twice as much persistence blur. I should note it is important that local dimming be set to "low" in order for BFI to be most effective on this TV. I am assuming this is because higher local dimming settings artificially over-brighten small window sizes. This could effectively increase the brightness of peak white in certain areas of the screen at certain times, which wastes backlight potential that could otherwise be used for lower persistence. The picture mode must also be set to Computer for full chroma to work and also to ensure BFI always flickers at the correct refresh rate, avoiding image duplications.

120hz pursuit camera screenshot [~1 ms of persistence blur (MPRT), ~100 nits]:
(960 Pixels Per Second)
120hz Frame.PNG
120hz Frame.PNG (266.48 KiB) Viewed 2814 times
120hz pursuit camera video: https://youtu.be/IlblA2qe-aw

100hz pursuit camera screenshot [~1.2 ms of persistence blur (MPRT), ~100 nits]:
(960 Pixels Per Second)
100hz Frame.PNG
100hz Frame.PNG (259.23 KiB) Viewed 2814 times
100hz pursuit camera video: https://youtu.be/A6Y_X5bBKgQ

IMPORTANT: For some reason, this TV cannot properly display a 100hz signal without chroma subsampling. I will post an update if I resolve the issue. You either need to set the picture mode to something other than "computer" or disable RGB/4:4:4 in your graphics driver settings. Attempting to send a full RGB 100hz signal will result in the bottom of the screen being cut off by a green bar.

60hz pursuit camera screenshot [~2 ms of persistence blur (MPRT), ~100 nits]:
(960 Pixels Per Second)
60hz Frame.PNG
60hz Frame.PNG (299.45 KiB) Viewed 2814 times
60hz pursuit camera video: https://youtu.be/FXTSvEsH3iw

NOTE: This TV is also capable of single-strobe 50hz BFI. It performs very similarly to 60hz but with slightly more blur and less strobe crosstalk. The flicker is extremely intense and I assume most people will never use it.

Any difference in color or brightness between the screenshots is due to the camera. Picture quality and brightness were identical for the three refresh rates tested. The moving aliens appear slightly less blurry in real life eye tracking then I was able to capture in these videos/screenshots. But I did my best. Likely limitations of an old camera and the hand-wave method. Also keep in mind the minor upscaling blur caused by displaying a 1920x1080 signal on a 4k panel (this was required for consistency at all refresh rates as the 2018 TV model tested lacks the HDMI 2.1 functionality required for [email protected]). I also tried to estimate the persistence/MPRT by comparing the clarity of the moving UFOs and pursuit photos to Blur Busters charts for visualizing persistence blur at 960 pixels per second. Please keep in mind that this is an amateur/end-user post and I lack any serious testing equipment.

I would also like to mention that it appears that this TV uses the local dimming zones to scan the backlight down the screen instead of strobing it all at once (somewhat like a CRT?). Anyone please correct me if I am misinterpreting this but I believe it to be a scanning backlight or rolling-strobe BFI. This could partially explain why I do not find the 60hz flicker of this TV to be particularly hard on the eyes, unless looking at an entirely white background. Rolling-strobe BFI should also in theory allow for maximally effective strobing on displays with local dimming as they can get brighter on smaller window sizes. The behavior at 50hz, 100hz, and 120hz is similar so I did not include slow motion videos for those refresh rates. I am curious if most TVs with local dimming do this? Do any monitors with local dimming do this?

Scanned 60hz BFI in iPhone 7 slow motion (play at 0.25 speed):
phpBB [video]


In terms of strobe crosstalk, it is basically perfectly uniform across the entire screen with 60hz BFI. At 100hz and 120hz BFI, strobe crosstalk varies across the screen. Strobe phase is unfortunately tied to the backlight setting at 100hz and 120hz (which also controls pulse width and perceived brightness). For example: I personally prefer ~100 nits of brightness while gaming. This corresponds to a backlight setting of ~0 on this TV during BFI. When the backlight is set to 0, 100hz BFI puts the least strobe crosstalk in the middle of the screen as most would prefer. At 120hz though, the backlight would need to be set brighter than 0, otherwise the sweet spot for strobe crosstalk is 80% up the screen and the bottom is less than ideal. 60hz strobe crosstalk works pretty much identically at all backlight settings.

My personal observations of this TV below:

Advantages:
- Scanned BFI could be slightly easier on the eyes and have lower input lag compared to other BFI methods
- Very low input lag on almost all modern 4k TVs
- Enabling BFI and/or game mode does not in any way change the overall picture quality, contrast, or local dimming performance (at least for Vizio TV's)
- Extremely deep blacks and contrast ratio with VA LCD and local dimming far exceed almost any ULMB/BFI monitor
- Native 60hz BFI works with any input including consoles and no need for a 60hz ULMB hack
- Pretty good pixel response times make strobe crosstalk not super noticeable, even at 120hz
- Industry leading HDR peak brightness and wide color gamut performance from TVs (especially ones with quantum-dot technology)

Disadvantages:
- 65" is far too large for typical desk usage
- Color washout and gamma shift with VA LCD at an angle (some expensive Samsung TVs have a "wide viewing angle layer" to compensate for this)
- VA black smearing often almost as bad as OLED
- Response time is not perfect and some strobe crosstalk is occasionally noticeable in games, strobe phase is not always where you want it to be at 100hz BFI and 120hz BFI depending on your preferred brightness

I can see TVs such as this one as being excellent for console gaming and emulation due to great picture quality and very effective 60hz BFI. The only thing stopping it from being excellent for PC gaming is its size. If you are able to use one for PC gaming though, there are some advantages. Many pretty AAA PC games cannot realistically be run at high frame rates so 60hz strobing is particularly helpful for improving the motion experience on those graphically and CPU-demanding titles. Content consumption is also especially improved, and I now find it difficult to enjoy YouTube or Twitch gaming videos without 60hz strobing. I am further tempted to say that one of these or a similar TV (especially a brighter one) would be an excellent low-persistence CRT-replacement for 60hz retro games without sacrificing much in terms of contrast ratio or picture quality (except for VA viewing angles). The native 60hz single-strobe BFI is just so immensely useful. It is such a shame that the vast majority of monitors will not even allow 60hz flicker by default. Furthermore, the difference in picture quality with local dimming enabled compared to a ULMB/BFI monitor is especially stark considering most monitors use TN or IPS technology with a poor contrast ratio (often made worse with ULMB/BFI enabled). The only major complaint I have of this TV overall is the viewing angles. I just hope "wide viewing angle layers" become more common among future VA LCDs. As a final note, I would be VERY INTERESTED to see pursuit camera tests done with Vizio's top-of-the-line Quantum X TV with a 3000 nit backlight. One could expect that display to perform three times as well as this one at motion blur reduction. At that point, it might be the best display available in terms of BFI capability. The Quantum X also appears to have the best BFI pursuit camera photos out of any TV reviewed on RTINGS.

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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by Chief Blur Buster » 11 Aug 2020, 14:13

Hey!

Firstly, welcome to Blur Busters.
JDnoob wrote:
07 Aug 2020, 13:03
Last year I bought a 65" 2018 Vizio P Series TV (P65-F1) with motion performance that impressed me enough to give pursuit photography a shot and post about it here. Below are some (no rail, amateur) pursuit photos with my iPhone 7. Although the production value is lower than ideal, it should hopefully be good enough to gauge the motion performance of this TV along with similar models. This model is advertised as having ~1000 nit backlight. I am very curious if brighter models such as the ~3000 nit P Series Quantum X could perform much better.
Secondly, fantastic hand-wave pursuit camera photography! The only real change in the future I might do is to turn off all room lighting (I saw some reflections), but that is very good freezeframe selection technique for your smartphone hand-wave video pursuit photography! You certainly studied the pursut camera HOWTOs, and executed the technique correctly, to the point that I can trust the strobe crosstalk is relatively WYSIWYG.
JDnoob wrote:
07 Aug 2020, 13:03
They are perfect for gamers looking for great motion performance and great dark room performance out of the same display. 60hz single-strobing also makes these TVs far superior for console gaming, emulation, content consumption (e.g. YouTube, Twitch), and PC games that are limited to 60hz or otherwise have difficulty running at higher frame rates (such as many AAA games).
(Paging Falkentyne: 50 Hz single-strobe BFI... This is a rare catch!)

Indeed. I've been working to convince gaming monitor manufacturers to add 60Hz single-strobe support, that is widely found in many HDTVs but rarely found in desktop gaming monitors. Some say it's a backwards step, while I say it's a sideways step (feature expansion) to include legacy framerate material that can never be benefitted by other technologies (60Hz consoles).

The slight strobe crosstalk is actually not too shabby for a VA panel. VA historically has a big problem with strobe crosstalk, but this is relatively decent for VA. I am somewhat surprised to see more strobe crosstalk for 60Hz than 100Hz, but as long as it's an early-timed pulse, that will reduce 60Hz strobed latency (in exchange for a bit more crosstalk).

(Aside: I wonder how a Quick Frame Transport (Large Vertical Total) 60Hz signal might increase/reduce strobe crosstalk on this panel, basically, a 60Hz signal with a 1/120sec scanout (vertical total 2250 instead of default HDTV vertical total 1125), although that would be PC-specific rather than console-capable.)
JDnoob wrote:
07 Aug 2020, 13:03
As a final note, I would be VERY INTERESTED to see pursuit camera tests done with Vizio's top-of-the-line Quantum X TV with a 3000 nit backlight. One could expect that display to perform three times as well as this one at motion blur reduction. At that point, it might be the best display available in terms of BFI capability. The Quantum X also appears to have the best BFI pursuit camera photos out of any TV reviewed on RTINGS.
It certainly looks like it, though comparing all the strobed refresh rates will be interesting!

Since strobe crosstalk is an independent variable than MPRT; In some cases, I would prefer a slightly higher MPRT for same brightness, but with less crosstalk. Since crosstalk is hugely influenced from the GtG pixel response speed moreso than a well-timed strobe pulse (though longer strobe pulses can enroach into the GtG curve creating more crosstalk).
JDnoob wrote:
07 Aug 2020, 13:03
Scanned 60hz BFI in iPhone 7 slow motion (play at 0.25 speed):
Nice! So the Vizio has a fairly decent scanning backlight. And this ordinary unassuming video reveals some strobe-backlight engineering surprises I didn't know Vizio was already doing (scanning + internal large VT). Nothing new to me, as I've long been famliar with all of these.

Blur Busters used to be www.scanningbacklight.com almost a decade ago before we renamed to Blur Busters. For most displays, a global-flash strobe backlight is superior for crosstalk because of lack of light leakage from ON-sections to OFF-sections. But this one seems to have relatively good backlight leakage control, so it may improve VA crosstalk (and lowers input latency) relative to a global strobe.

There's a hard-to-optimize strobing performance threshold where a scanning backlight turns from worse-than-global-strobe to better-than-global-strobe, and it appears that this Vizio passes the necessary threshold.

I also additionally observe that your high speed video is completely black frames for 1/240sec. Since you adjusted for full-open shutter (is the slo-mo video 1/240sec shutter 240fps?). If so, that means your backlight was completely off for a minimum of 1/240sec, which also means it must use internal VBI-lengthening techniques simultaneously to add more GtG-settlement time between refresh cycles. This is because the VBI of a 60Hz 1080p signal is only 1080/1125ths of a 1/60sec (about ~0.5ms), and 1/240sec is almost ten times longer.

So the high speed video is a huge engineering clue of how the scanning backlight reduces VA strobe crosstalk, high contrast between ON section and OFF section, probable large vertical distance (on other side of GtG fade zone) between the panel scanout and scanning backlight illumination zone, Internal large vertical total, using scan-conversion technique, to reduce strobe crosstalk

(I wouldn't mind you filming www.testufo.com/scanout -- even if 240fps is your highest speed -- in a similar way that I did the High speed videos of display scanout as well as Red Phosphor)

This simultaneous combination of automatic internal large vertical total (scan conversion), combined with a scanning backlight of a custom scan velocity (slightly faster than 60Hz signal scanout, since VBI on a signal is longer than 1/240sec).

For more information about fixed scanrate panels, see this post. This technique can be used in simultaneous conjunction with a strobe backlight or scanning backlight, to reduce strobe crosstalk.

Image

While this is a 60Hz-on-240Hz diagram, the Vizio is probably doing a 60Hz-on-120Hz, which is still sufficiently good opportunity for VA strobe crosstalk reduction.

The Vizio might be doing something similar to this already, to intentionally create a VBI large enough to hide VA LCD GtG between refresh cycles (owing to your long 1/240sec blackness in your high speed video that seems to indicate a panel-based or backlight-based VBI longer than the VBI of a typical 60Hz signal).

The simultaneous combination of scanning + higher velocity (than the Hz) scanning backlight + longer VBI + high contrast between ON/OFF segments, is creating a winning combination for reducing VA strobe crosstalk.

I've included this thread into the Area51 forum since this is an actual hardware implementation of Blur Busters combo recommendations for reducing VA strobe crosstalk with a scanning backlight. I don't know if it was Vizio existing knowledge or if they used the great universe of Blur Busters knowledge, but this is the Blur Busters known winning combo for scanning backlights
1. VBI lengthening technique being done (backlight level, or both panel/backlight)
2. High contrast local dimming (OFF segment stays dark when ON segment stay bright)
3. Scanning with reasonable strobe phase tuning (backlight scanning phase sufficient distance away from phase of GtG)
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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by AddictFPS » 15 Jan 2021, 22:19

Shocking discovery !! Good work ! :)

High quality strobing backlight, taking the best of LCD. Excellent result, and using only 120Hz scanout speed. I can't wait to see it implemented over current FHD 360Hz panels + BlurBusters Approved

To see in detail the rolling scan, pause video and use keys "," and "." for previous/next frame.

Up to 3,000 nits peak FALD + Rolling Scan, all toghether single strobing high refresh LCD. I never see any gaming monitor using all these technologies toghether during strobing. In fact, those with FALD that i know, not support strobing. And Rolling Scan in monitors missing since CRT.

More the FALD zones, with proper design against light fugues, more close to OLED/MicroLED contrast, and also cause Glow minimized in black areas. If is good isolated light Off, can't have fugues from any angle. This is very interesting for 21:9 films over 16:9 screens, black bars like OLED, side spectators without issues.

Well isolated FALD maybe it is what improve Samsung VA viewing angles in high end models. I think is not a coating feature, beause i have one old Samsung TV 40" VA FHD 60Hz 8000 series, with FALD named "Micro Dimming Ultimate", excellent black, even at angles, and has Glossy finish.

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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by JDnoob » 16 Jan 2021, 00:27

Well isolated FALD maybe it is what improve Samsung VA viewing angles in high end models. I think is not a coating feature, beause i have one old Samsung TV 40" VA FHD 60Hz 8000 series, with FALD named "Micro Dimming Ultimate", excellent black, even at angles, and has Glossy finish.
I'm going based on Rtings reviews. They claim it is because of a coating. It makes a lot of sense as this coating also decreases the contrast of VA panels on-axis. I would read through the Rtings review of the Samsung Q90T or the likes to see where I got my info.

Better Glimpse at 60hz Single-Strobing Scan-Out Behavior on Vizio P65-F1
phpBB [video]

This is only at 240fps and the iPhone 7 gives me no other info as to shutter speed or the likes. My more advanced camera app doesn't have a slow-motion option either. I was going to post this much sooner but I really wanted a 960fps camera. One day, one day...

Just for Fun, here is proof of 50HZ!!! Single-Strobing. Very good - around 2ms MPRT at 100nits. Crosstalk basically non-existent.
phpBB [video]
IMG_0124.PNG
IMG_0124.PNG (141.67 KiB) Viewed 2210 times

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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by AddictFPS » 16 Jan 2021, 14:02

Thanks !

Even at 50Hz, with 20ms betwhen frames, VA GtG can't be fuly hided, some transitions exceed a bit this value, causing very subtle crosstalk. Is needed a big jump in GtG, and more rolling granularity to take full advantage of GtG to reach 100% crosstalk free at flicker-free frequencies.

Rtings P65-F1 60Hz single strobe picture is almost perfect, very good TV, most GtG are inside 20ms window, crosstalk here is almost undetectable, but is at center of screen. They should take also Up/Down and all strobed frequencies availables, hope they update this to go deep in future reviews, worth it, your work here is good proof of it ! :)

https://www.rtings.com/tv/reviews/vizio/p-series-2018

Image

Oscilloscope picture confirm some dark GtG above 20ms, and Vizio only apply overdrive in GtG over 8.33ms, exactly the 120Hz goal. This is why these curves show overshot and the rest are perfect. Very good work at Vizio also with overdrive, only where is needed, and the offset relative to the GtG offset over 8.33 :)

https://i.rtings.com/images/reviews/tv/ ... -large.jpg

GtG 100% max. 22.2ms for VA panel is very fast, taking into account than last Samsung G5 monitor has 41.7ms in this same (0 to 20) transition, with recommended overdrive fast, but even with fastest only reach 35.2ms

https://www.rtings.com/monitor/reviews/ ... odyssey-g5

Image

No matter if Vizio (0 to 20) has heavy overshot, because is fuly hided during short MPRT :)

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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by Chief Blur Buster » 21 Jan 2021, 01:16

JDnoob wrote:
16 Jan 2021, 00:27
Better Glimpse at 60hz Single-Strobing Scan-Out Behavior on Vizio P65-F1
phpBB [video]

This is only at 240fps and the iPhone 7 gives me no other info as to shutter speed or the likes. My more advanced camera app doesn't have a slow-motion option either. I was going to post this much sooner but I really wanted a 960fps camera. One day, one day...
That is damn good quality strobing.
Lower framerate cameras usually actually amplify the appearance of strobe crosstalk, but I'm able to detect none. I still welcome 240fps footage.

And did you know you can buy a beat-up Sony Xperia XZ Premium (damaged, but with camera good) off eBay for $150-200? Even locked, just use WiFi and camera only. It has a 960fps HD camera perfect for display scanout research.
AddictFPS wrote:
16 Jan 2021, 14:02
Even at 50Hz, with 20ms betwhen frames, VA GtG can't be fuly hided
Actually there's a trick. Just massively overdrive, then strobe when the colors cross the destination value (like a camera flash, photographing the correct color), and let the overshoot mess happen unseen in total darkness. Some crazy clever strobe tuning does that.

RTINGs' and JDnoob's evidence seems to show a really good strobe job -- the high speed videos of www.testufo.com/scanout shows a pretty good job with a large gamut of transitions. If that Vizio is pretty crosstalk-free, I'll have to say they've done a superlative job in virtually complete GtG transitions between strobe flashes. Hiding VA transitions in the dark cycles between transitions.

Remember....Look at what happened to IPS panels, they were too slow to be good strobed, then they became strobing par excellence. There are probably faster-than-average VA specimens, when combined with advanced engineering (Y-Axis compensated Overdrive Gain algorithms and/or scanning backlights), might go practically crosstalk free.

VA is very, very hard to strobe-tune though, but it appears Vizio did a kick ass job.

In fact... VA used to be better quality for strobing more than 5 years ago. Because of stereoscopic 3D. The overdrive algorithms back in the day was superior. They've slacked off on precision overdrive tuning.
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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by JDnoob » 27 Jan 2021, 22:24

Here is the best case and worst case strobe crosstalk at 120hz (75% up the screen vs the very bottom of the screen). Not too bad and totally usable. I apologize for the differing exposure/color.
IMG_0126.PNG
IMG_0126.PNG (177.48 KiB) Viewed 1941 times
IMG_0125(1).PNG
IMG_0125(1).PNG (175.43 KiB) Viewed 1941 times
Crosstalk really isn't really a problem at 100hz and below. 100hz strobing on the Vizio is almost subjectively perfect in terms of crosstalk in-fact. Note that black smearing can become a bit of an issue in some games. Black smearing on the Vizio is certainly no worse than the OLEDs I've used though. When I say black smearing, I'm generally referring to the dark grey<--->black transition.

The most impressive thing about the Vizio IMO is how local dimming remains fully functionally and quickly adapts to on-screen content simultaneously with the rolling-strobe BFI and very low input lag (relatively speaking).
AddictFPS wrote:
16 Jan 2021, 14:02
Rtings P65-F1 60Hz single strobe picture is almost perfect, very good TV, most GtG are inside 20ms window, crosstalk here is almost undetectable, but is at center of screen. They should take also Up/Down and all strobed frequencies availables, hope they update this to go deep in future reviews, worth it, your work here is good proof of it !
Crosstalk variation is extremely negligible at 60hz. There is next to zero perceptible difference anywhere on the screen. So what you see in the middle is pretty much identical to what you get at the extreme top and bottom as well. It noticeably varies at 100hz and 120hz though as displayed above.

Rtings could definitely do a lot better if they just added a little more depth to their BFI analysis. You can infer a lot of information with their luminosity/time graphs under the PWM dimming section and under the BFI section (although I'm not sure if the methodology is 100% consistent for all TV's). Because the PWM dimming frequency is 120hz on the Vizio, it approximates the 120hz BFI behavior. That PWM graph could therefore give you some info on the rolling strobe at 120hz. The only real difference between BFI on/off at 120hz in-fact seems to be that the backlight is put into overdrive with BFI on, which lowers MPRT a bit more. Strobe phase also changes somewhat. The evidence gathered from the PWM graphs also seems to indicate that the P-Quantum X would well outperform the P65-F1 currently tested, leading to ridiculously low MPRT.
Chief Blur Buster wrote:
21 Jan 2021, 01:16
And did you know you can buy a beat-up Sony Xperia XZ Premium (damaged, but with camera good) off eBay for $150-200? Even locked, just use WiFi and camera only. It has a 960fps HD camera perfect for display scanout research.
Awesome! The only thing holding me back is I plan on buying a new phone soon anyways which I will ensure has true 960fps. I'll further make sure to have a 960fps camera on hand whenever I get around to buying a P-Quantum X (I will whenever Vizio fixes the issues on the 2020 model or next years model) for that [email protected] sub-1ms MPRT sweetness!

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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by Chief Blur Buster » 27 Jan 2021, 22:41

Thanks for providing this feedback!

That's what I thought. Seems like it's extremely good for a strobed VA panel 60-100Hz, but has some difficulty at 120Hz.

It's probably recycling refreshrate headroom to reduce strobe crosstalk, as is recommended strobe-tuning practice. It's essentially refreshing a 60Hz refresh cycle in 1/120sec, to speed up a refresh cycle and let GtG complete between refresh cycles. (Such as emulating Vertical Total 2500 out of a standard Vertical Total 1125 from HDTV 1080p standard, via buffering the signal and doing a fast scan-out to panel)
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Re: Vizio P65-F1 Pursuit Camera Tests and Review, 60hz Single-Strobing, 100hz, 120hz, TV BFI Discussion

Post by JDnoob » 28 Jan 2021, 17:40

Fullscreen Crosstalk: 120hz on P65-F1(top) vs. 119hz on XG270 for reference(bottom):
IMG_0198.PNG
IMG_0198.PNG (342.06 KiB) Viewed 1912 times
Screenshot 2021-01-28 135657.jpg
Screenshot 2021-01-28 135657.jpg (87.21 KiB) Viewed 1912 times
Source: Blur Busters User Ansive - viewtopic.php?t=5998&start=220

I used pursuits because the rolling-strobe makes pictures nearly impossible to take. I think the XG270 with pureXP does a little better, but the fact that they are this close is very impressive, especially considering the Vizio is at its maximum refresh rate. The Vizio struggles a little bit with the 100% response time so you can see extremely faint crosstalk even in the sweet spot.

P65-F1 at 100hz might be better if you're sensitive to crosstalk:
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IMG_0188.PNG (340.76 KiB) Viewed 1912 times
MPRT is still ~1ms 100nits.

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