Discussion about Display Motion Physics (BFI, Color Mixing, Video Issues, Etc)

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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by Chief Blur Buster » 17 Nov 2021, 19:02

First of all, that is the wrong paper.
That's the motion threshold paper, not the sample-and-hold paper


There are different effects cased by a finite refresh rate & frame rate
Motion threshold -- 7 to 13 (Hz=fps)
Flicker threshold -- about 70 (Hz=fps)
Motion blur threshold -- approximately 1000 (Hz=fps)
Stroboscopic threshold -- approximately ~20,000 (Hz=fps)

You might be getting dizzy from looking at too many TestUFOs for too long.
Take breaks.
That way, you will be less tired.

I'd rather continue because if I haven't helped you understand displays better, then Blur Busters has to create new articles that caters to your specific type of thinking, to help explain things better. I'm a born-deaf researcher so I am not a YouTuber (at this time) due to my hearing impairment. So I often write articles, but some people don't always understand my articles.

Take a deep breath and re-read my earlier posts with the new understanding you gained. You might get on track better that way.
mynm wrote:
17 Nov 2021, 17:24
thanks for the info. I see now that at the Eye Tracking Motion Blur - Optical Ilusion test what is conpleting the white line gaps is the motion blur from persistence, I understan right?
Correct.
mynm wrote:
17 Nov 2021, 17:24
it's not explained at the web and the video.
It is already explained halfway down at www.blurbusters.com/1000hz-journey -- it is a bit of a long read, but an important read for those who want to understand display science.
mynm wrote:
17 Nov 2021, 17:24
And the last thing I want to know is if at all the videos I did, the mixed frames are caused by the MPRT as well. That is something I was thinking possible and asking you, but you didn't have answered it clearly. I didn't know MPRT was as high, to do that, I see you have explained it at one post but I was not undesrstandig that it was causing the mixed images even at the 60 fps line.
What are you referring to when you say "mixed images"? Be specific.
When you say "mixed images", do you mean the double image effect from software based black frame insertion?
mynm wrote:
17 Nov 2021, 17:24
Editd: Sorry, I don't have understand if is a persistence how is it going to have a effect to all the nex frame, if is at a different possition.It will have am effect in some its area not all of it. I don't know what I am saying. I am tired. I don't undestand what you are saying.
If you're referring to software based black frame insertion, remember that software based black frame insertion is simulating a CRT by using multiple frames to simulate a CRT refresh cycle. So you have to think about it from the perspective of the pixel, and the pixel visibility time.

Because SOFTWARE-based black frame insertion can't flicker a frame at less than one refresh cycle (like a CRT can, or a strobe backlight can), it needs to add extra frames in extra refresh cycles to add the flicker to simulate a CRT.
So it has to emulate a CRT refresh cycle by using multiple LCD refresh cycles.
That's why a 60Hz LCD using software-based black frame insertion can only emulate a 30Hz (or less) CRT.

Maybe this is what is confusing you about frame mixing?
You might want to re-read my earlier posts with this understanding.

Sometimes refresh cycles and frames diverges, and sometimes you have to "pretend" a refresh cycle is multiple refresh cycles. A frame being repeated is a essentiallydo-nothing operation (screen doesn't change) on a sample-and-hold operation. It's also why 60fps has identical motion blur at LCD 60Hz, LCD 120Hz and LCD 240Hz. So motion blur is linked to frametime. You don't have a duplicate image effect on sample and hold (without black frame insertion), so a given frame rate at any higher Hz, is effectively the same (visually) as the lower Hz.

Only hardware-based flickering (e.g. CRT or strobe backlight) can flash a refresh cycle briefer than the time interval between refresh cycles.

Sample-and-hold displays are stuck with an MPRT that can never be less than the interval between refresh cycles
mynm wrote:
17 Nov 2021, 17:24
“For example, if you take the motion detection of small object, what is the optimal temporal frequency of an object that you can detect?”
And studies have found that the answer is between 7 and 13 Hz. After that, our sensitivity to movement drops significantly. “When you want to do visual search, or multiple visual tracking or just interpret motion direction, your brain will take only 13 images out of a second of continuous flow, so you will average the other images that are in between into one image.”
This seem the study. I have not read it .
This is correct. However, it only "drops significantly". It does not "drop to zero". Also, don't use this research paper to try to explain things in this thread, because that research paper covers a different threshold than the thresholds we are discussing in this thread

Also, this is a different threshold than the flicker/stutter detection threshold.

it drops fully to zero at roughly the flicker fusion effect.

Remember there's MANY different frequency thresholds of detection.

The Multiple Human Thresholds Pertaining To Display Motion
  • Motion threshold -- 7 to 13Hz
    As a lot of research shows. Basically this is when things stop looking like a slideshow and finally looks like motion
  • Flicker threshold -- approximately 70Hz
    this pertains to the stutter detection threshold, where stutter vibrates too fast, and becomes blur. Faster GtG will lower the flicker threshold. However, your sensitivity to stutter (on sample-and-hold) is actually linked to your sensitivity to flicker.
  • Motion blur threshold -- approximately 1000Hz (can be higher or lower depending on display resolution, size, FOV, etc)
    this will vary, e.g. Vicious Cycle Effect)
  • Stroboscopic threshold - approximately 20,000Hz (similar variables)
    this was already studied, and is very common on displays too
Example:
Image
From this lighting-industry research paper but it also applies to displays too:

Image
From The Stroboscopic Effect Of Finite Frame Rate Displays

Image

Display motion does not match real life as long as at least one weak link exists.
Fixing the motion threshold (like 30fps) does not fix the stroboscopic-effect threshold yet.

Try to avoid confusing the multiple different thresholds

Also: A display cannot match real life if at least one weak link exists (motion threshold, flicker threshold, motion blur threshold, stroboscopic threshold, etc). That's why we need retina refresh rates at the >1000Hz leagues, as explained at Blur Busters Law: The Amazing Journey To Future 1000Hz Displays.
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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by mynm » 18 Nov 2021, 04:16

Chief Blur Buster wrote:
17 Nov 2021, 19:02
First of all, that is the wrong paper.
That's the motion threshold paper, not the sample-and-hold paper
Ok. Thanks thank for saing that it's wrong and the below explanation, I will try to undesrstand it.

Chief Blur Buster wrote:
17 Nov 2021, 19:02
mynm wrote:
17 Nov 2021, 17:24
thanks for the info. I see now that at the Eye Tracking Motion Blur - Optical Ilusion test what is conpleting the white line gaps is the motion blur from persistence, I understan right?
Correct.


Ok. Thanks.
Chief Blur Buster wrote:
17 Nov 2021, 19:02
mynm wrote:
17 Nov 2021, 17:24
it's not explained at the web and the video.
It is already explained halfway down at www.blurbusters.com/1000hz-journey -- it is a bit of a long read, but an important read for those who want to understand display science.
I will read it.
Chief Blur Buster wrote:
17 Nov 2021, 19:02
mynm wrote:
17 Nov 2021, 17:24
And the last thing I want to know is if at all the videos I did, the mixed frames are caused by the MPRT as well. That is something I was thinking possible and asking you, but you didn't have answered it clearly. I didn't know MPRT was as high, to do that, I see you have explained it at one post but I was not undesrstandig that it was causing the mixed images even at the 60 fps line.
What are you referring to when you say "mixed images"? Be specific.
When you say "mixed images", do you mean the double image effect from software based black frame insertion?
Videos like this one:
mynm wrote:
10 Nov 2021, 13:31
Is not a distorsion artifact is what I have edited. That frame is from a 30 Hz video but I have a 60 Hz one. And what I have edited is this:

Image

At the 60 fps line, in one frame the ufo is red and at the next green.

At the 30 fps, in one frame the ufo is red, the second a black patch and the last a green ufo. Like I said here:
mynm wrote:
07 Nov 2021, 15:05
Or this one:
mynm wrote:
11 Nov 2021, 14:57

I have done a 60fps video with the ufo static and only changing the color from red to green form one frame to the next for one minute, to see if the frame color mix is the same at an static image as in a motion one. This is the edited video, is not a camera record is done with a video.

I have tested it at a CRT at 60hz and at a LCD at 60Hz. And the ufo color is static, is a dark red as a mix of bright red an the dark green.
Or this ones, for the counter from one to two:
Chief Blur Buster wrote:
14 Nov 2021, 18:34
Sorry, I was not undesrstanding that it was retina perdistence that was doing the colors to be mixed at the 60 fps line. So while you are chasing the ufo in motion with your eyes the retina persistence is mixed with the next frame as the it is at the same position at your eye, and is the same as at an static ufo changing the colors. And at the counter from one to two the retine persistence is was is masking the one behind the two. I am right?.

I didn't have see this anywhere. This is like I said, is like 60 fps ar a mix of two at 60Hz.

I will read the rest of your post and try to undesrstand and answer it.

Edited: So don't could be the retine persisntence edited: (flicker fusion threshold) doing the same as I said here but avoiding calculations to the brain, so is very useful:
mynm wrote:
14 Nov 2021, 21:58
I didn't have read this anywhere, it is useful for that type of things.

Edited: it seems is named flicker fusion threshold not retina persistence is no true. I was namig it like that because you sait this because you what you said here:
Chief Blur Buster wrote:
08 Nov 2021, 16:11
mynm wrote:
08 Nov 2021, 15:09
I don't see that I see a none doubled image at 45hz or 50hz with my current CRT and I had tested this whit another two ones years ago.
Please refer to this diagram:

Image
Hz = flicker Hz (not necessarily refresh rate Hz)

One flash per static frame = one image (when tracking eyes)

Two flash of the same identical static frame = double images (when tracking eyes)

etc.

If you're testing CRT at 50Hz, please test 25fps.
If you're testing CRT at 45Hz, please test 22.5fps.

TestUFO double image animation creates the double image effect in pure software via this:
Sequence 1 of 4 = flash a frame
Sequence 2 of 4 = black frame
Sequence 3 of 4 = flash the same unchanged frame as sequence 1
Sequence 4 of 4 = black frame

Your eyes are analog and following the UFO in its vector. Your eyes are in a different position in Sequence 3 than in Sequence 1, so the identical frame (in same old pixel positions) are flashed in a different location of your retinas. So you get a double image during the eye-tracking situation.

For CRTs, they naturally flicker, so CRT 30fps at 60Hz looks like
Sequence 1 of 2 = flash a frame (CRT naturally flickers)
Sequence 2 of 2 = flash the same frame (CRT naturally flickers)

The constant is repeated flash of the same frame = duplicate image.
So is it the same effect but at the same frame?.

Edited:

OK it seems is MPRT. At LCDs all frames are mixed because of the MPRT, so colors are mixed as well. This is a think I was understanding.

CRTs don't have trails beause of the lack of tespose but they still have an MPRT that I didn't know was as high to cause the 30 fps line to be duplicated and colors to be mixed at the 60 fps line. I think I did not understand the above explanation.

So at CRTs like yuo say, "the constant is repeated flash of the same frame = duplicate image" because of the MPRT.

I don't know how I was misunderstanding all the things. I don't see any duplicated image at the CRT only some white trainls, so that it made me thing CRTs didn't have any persistence of the previous frame. So the MPRT is what is causing the mixed colors and the 1 not been seen for four frames covered with the 2.

Sorry I apologize for all this misunderstanding and all your inverted time.

But could you explain at least one of my videos to get a clarifications of why the things I see at the video are happening at CRTs and LCDs, please. This thread is one of the first search at internet searches, even I am not sure if MPRT is the cause, if some one get here will not understand anything and will be overwhelmed with the info as I am.

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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by Chief Blur Buster » 18 Nov 2021, 16:28

mynm wrote:
18 Nov 2021, 04:16
I don't know how I was misunderstanding all the things. I don't see any duplicated image at the CRT only some white trainls, so that it made me thing CRTs didn't have any persistence of the previous frame. So the MPRT is what is causing the mixed colors and the 1 not been seen for four frames covered with the 2.
Just to be clear...

CRTs have extremely low MPRTs. That said, MPRT doesn't really have any effect on the color mixing except as how it pertains to pulse width duty cycle. (Shorter pulses of light to longer periods of darkness). So lower MPRT means shorter pulse of light and longer duty cycle. Like a tiny square wave.

Also, MPRT stands for Moving Picture Response Time, which is explained in Pixel Response FAQ: GtG Versus MPRT.

____

Sometimes the problem is that I don't understand the question you are trying to ask me without a "show and tell" in person. To see what you're seeing on a specific display, in real time, and in video. So sometimes my answers are much more generalized and blanket. Some of us use different terminology (words) to describe exactly the same thing. At the moment I'd have to reread what you say to understand exactly what you're asking. However, the thing about duty cycles also applies. It's easier to see color mixing effects at different duty cycles.

MPRT has nothing to do with duplicate images, and I didn't say anything like this. You might've misunderstood a sentence or two. Except insofar as to how blurry each individual duplicate image is. For example, the double-image test is blurrier on LCD than on CRT. Color mixing is a different effect than motion blur reduction, although both effects can happen at the same time for various different technological reasons on some displays (e.g. temporal dithering effects). Since I am not able to see what you see on your very specific unique display, and I may be seeing something else entirely on my particular display. It is not easy to explain effects especially when it comes to common boilerplate 60Hz displays that gives some severe limitations to my ability to teach display education.

So, as a result, I'm not even sure if you're talking about black frame insertion, or talking about color mixing separately (different effect), or both effects combined at the same time. But let's talk about black frame insertion first, because you incorrectly say MPRT creates duplicate images. That's not true, and I never said that. It has an effect but it does not change the number of duplicate images. MPRT is just happenstance of being high on a sample-and-hold display, but the existence or lack of black periods available is the factor that generates the duplicate images.

____

So I will start again, focussing only on black frame insertion & double image effects (ignoring the "color mixing" topic temporarily for now). Let's make suer you understand this first, before we start discussing the separate topic of color mixing, please. Put a pause on the "color mixing" topic first, let's teach one thing at a time.

Higher MPRT per refresh cycle = more blurry duplicate images. But the duplicate image effect is there regardless of MPRT, as long as there's blackness between repeat-frames. Duplicate image is caused by repeat flashes of unchanged frames (Frame-OFF-(same frame again)-OFF) in a 4-step cadence.

Sequence For Double Image Effect On ALL Displays, Independently Of Whatever MPRT IS
Object in motion, but with each frame being repeated two times with an off period in between.
1. VISIBLE FRAME (frame)
2. BLACK (black frame)
3. REPEAT VISIBLE FRAME (same unchanged frame)
4. BLACK (black frame)

This is what causes the double image effect, because your eyes have moved to a different position.

Reproducing Double Image Effect on CRT Requires Framerate 1/2 Hz
Example: CRT 30fps at 60Hz. The 4-step cadence only needs 2 refresh cycles to occur on a CRT. This is because there's an OFF period. The CRT naturally flickers each pixel in less than one refresh cycle. Pixel is on briefly (less than 1ms) and the pixel is OFF until next refresh cycle. That's why CRT has low motion blur, and why CRT easily creates double images with just half frame rate.

1st CRT refresh cycle: Frame is flashed and becomes black again (natural CRT flicker)
2nd CRT refresh cycle: Same unchanged frame is flashed and becomes black again (natural CRT flicker)

This matches the "Sequence" for "Frame-Black-RepeatFrame-Black" mentioned above

Reproducing Double Image Effect on Non-Strobed Sample-And-Hold Displays Via Software BFI Requires Frameraet 1/4 Hz
The 4-step cadence requires 4 refresh cycles to occur with software-based black frame insertion on LCD, because you need extra refresh cycles to add software-based black frames. Sample-and-hold displays are unable to flicker the picture without any special blur reduction mode (such as a strobe backlight).

1st nonstrobed LCD refresh cycle: Frame is continuously displayed for whole refresh cycle
2nd nonstrobed LCD refresh cycle: Black frame
3rd nonstrobed LCD refresh cycle: Same unchanged frame is continuously displayed for whole refresh cycle
4th nonstrobed LCD refresh cycle: Black frame

This matches the "Sequence" for "Frame-Black-RepeatFrame-Black" mentioned above

Understanding The Double Image Effect Is By Understanding the Sequence of Photons Hitting Your Eyeballs

Your eyes are analog
1. During VISIBLE, your eyes are moving a bit further forward
2. During OFF, your eyes are moving a bit further forward
3. During REPEAT VISIBLE, your eyes are moving a bit further forward (it appears in a different position on your retinas so it become a duplicate image)
4. During OFF, your eyes are moving a bit further forward (before next unique frame)

Because your eyes are continuously moving in a straight line, even as the frame suddenly steps-repeat-steps-repeat-steps-repeat-steps forward (between black periods), the screen is literally defacto photoflashing a new image onto your retinas in a different position of your eyeball's retinas. So you are seeing a double image effect.

Double Images Effect Is Not Caused By MPRT

Double image effects are not caused by MPRT, and I never said it was. You may have gotten confused. I simply mention that sample-and-hold displays have very high MPRT, and has more motion blur. MPRT is about motion blur, not about double image effect.

A possible accidental misunderstanding is that sample-and-hold displays (high MPRT) requires software-based black frames in order to generate the black frames. But that doesn't mean the MPRT itself is creating the double image effect.

(Note: Double image effect is simply an interrupted motion blur effect in another way of thinking, because motion blur is caused by a continuously visible image being smeared across your retinas, as a result of eye-movement, like www.testufo.com/eyetracking .... and double image effect is essentially gaps in the motion blur, because you've got black inserted in the middle of the frame. However, this might not be the best way for you to understand motion blur vs double image effect)

While multiple methods of measuring MPRT exists:
MPRT(100%) is equivalent to pixel visibility time.
MPRT is the length of time a frame begins becoming visible, and stops becoming visible.

Double image effect is simply MPRT repeated twice instead of once.
Short MPRT double image effect = very clear double images (like on a CRT)
Long MPRT double image effect = two blurry double images (like software BFI on LCD).

MPRT only affects the image blurriness, not the existence of the double image effect.
Blurriness can make it harder to see other effects (such as color mixing) but we're not talking about that yet.
I want to make sure you understand MPRT first before we talk about color mixing.
I want to make sure you understand double image first before we talk about color mixing.

Let's make sure we are clearer, and let's make sure we learn one thing at a time.
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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by Chief Blur Buster » 18 Nov 2021, 20:54

And just to be clear, if you're still confused:

Take a look at the new red asterik note:
Image

This caveat is not normally necessary to include because "impulsed displays" is hardware-based BFI. Terminologically, impulsed displays are displays with hardware-based strobing/impulsing/etc. (CRT, strobe backlight, or other natural hardware-based flicker that occurs without needing extra refresh cycles to generate the flicker)

Which means this chart needs to be interpreted differently for sample-and-hold displays that emulate impulsed displays via software means (software BFI).

Remember double images is caused by repeated frames between periods of black, in this four-sequence recipie:

- Frame
- Black
- Repeat Frame
- Black

This creates a double image effect regardless of whatever MPRT is (high or low). It just simply means that for sample-and-hold displays, you have to manufacture the black frame using software in a separate refresh cycle (since flicker is not built-in into the display).

So it takes a minimum of 4 sample-and-hold refresh cycles to meet the "minimum system requirements" of reproducing a double image effect via 100% software means on a sample-and-hold display. So double image effect at 1/4 the refresh cycle (unlike CRT where a duplicate image can occur at frame rate 1/2 refresh cycle. This is because both the frame and the black period is built into the same refresh cycle, because of natural CRT flicker.

Basically, CRT phosphor is its own hardware-based black frame insertion that can occurs with the same refresh cycles.

Let's make sure you understand this first before we go back to talking about color mixing (understand this topic before addressing the subject matter of the color mixing effects)

Color mixing effects is a slightly more advanced topic (that I do understand) but it's important to learn the pre-requisites first.
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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by mynm » 19 Nov 2021, 03:41

Thanks for all the info.

Yes, I undrerstand that a black frame or a flicker is doing the double image effect and now that MPRT is no causing it. But at the compare frame rates: ufo test , I see a double ufo effect at the 30 fps line at my LCD, do the test have black frame insertion?.

I also have a question about the eyetraking motion blur - optical illusion. At the CRT, are the white wavy lines you see when chasing the lower ufo the motion blur?, So are this previous static lines displaced to the right like motion blur?. And are the black ones the MPRT, so at the LCD them are white because it is hight for them?.

Is weird but the eyetraking motion blur - optical illusion test is like a double-slit experiment. Is like when you look at the lines the light is a particle, but when you chase the ufo you see the light like a wave edited: and in motion. So is motion blur the wave of the previous frame displaced to the right?.
It fits curiously well and that could cause the color and frame mix. I am only speculating and joking, I am not saying is like that, I only have watched that experiment in some scientific didactic videos years ago and the test reminded me them :D .

Edited: also the doble image after a black period, you are seen the border of the waves of tre two ufus as the waves were covered by the black period at the center and you didn't see the light. :D

Edited: I see now at the rting video that the blur is caused as the frames are jumpimg in steps at it cause the blur I didn't heve remembered it, sorry.

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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by Chief Blur Buster » 19 Nov 2021, 13:09

Aha, now I understand your 30fps question better.
(I’ll answer the other question later)

There are two main common causes of seeing duplicate images without impulsing of any kind, such as 30fps on LCD at www.testufo.com
One or the other.

1. Possible Cause #1: Extremes of the stutter distance (amplitude)
The two extremes of the stutter amplitude can sometimes create a faux double image effect, when framerates are in an intermediate region (between approx motion threshold and approx flicker fusion threshold) such as frame rates above 15fps and below 60fps (very approximate, fuzzy blended, thresholds).

It’s like how sometimes a vibrating guitar string looks like two strings with a blur in between two strings. So it’s an optical illusion caused by counting the opposite extremes of the vibration of stutter. This is not a true photographable/videoable double image effect (true black gap in persistence), but an illusion that occurs at intermediate frame rates.

You also see the same effect on a display at www.testufo.com/eyetracking#speed=-1&pattern=lines2 where the lines sometimes vibrate until it looks like 2 lines (at slower speed 30fps) before it becomes fully blurry (at full speed 60fps).

2. Possible Cause #2: PWM dimming.
Do you know if your LCD backlight is doing PWM dimming?
Your backlight might be doing “PWM dimming”. Google “PWM dimming in displays” for a lot of info. It is also explained in the article, LCD Motion Artifacts.

That’s a method of unsynchronized strobing for screen brightness dimming purposes (instead of motion blur reduction). But it has the same side effect as “Duplicate Images on Impulsed Displays”.

If your 30fps is interacting with 180 Hz “PWM dimming” backlight, then ignore the LCD refresh rate Hz temporarily, and instead count the backlight Hz. 180 (pwm) divided by 30 (fps) equals 6. So there will be six duplicate images for 30fps at 180Hz PWM backlight. It would look approximately like:

Image

This wont happen on all LCDs, because it is backlight dependant, if you know your LCD uses a “PWM free” backlight or “DC dimming” backlight, then it is probably instead cause #1 on LCDs if you see double images without software BFI.

Be careful not to confuse the true double image effect (interruptions to persistence with blackness in middle of repeated frames) with the optical illusion effect (the furthest extremes of the stutter). They can make interpretations confusing.

Let’s make sure we understand this specific effect before we move onto discussing color mixing…
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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by mynm » 19 Nov 2021, 15:05

Chief Blur Buster wrote:
19 Nov 2021, 13:09

1. Possible Cause #1: Extremes of the stutter distance (amplitude)
I will try to understand this and response you.

Chief Blur Buster wrote:
19 Nov 2021, 13:09

2. Possible Cause #2: PWM dimming.
Yes it have PWM dimming, but I remember to read at a review that at 100 % brightness it don't have it. So with it at 100% I didn't see the multiple image, and moving the hands in front of it I see a complete train between the fingers and at 30 fps line I still see a double ufo. The right one is more dark than the left one. Is maybe a lack of response what is making it to be seen?. I also have tested it on one CCFL monitor and I see a double ufo at the 30 fps line aswell, and I remember to see it in all the monitors or TVs I have rested to see its response with your test.

And I have one question about the eyetraking motion blur - optical illusion test. Seen it with a CRT, what are the white wavy moving lines and the black lines I see when chasing the ufo?, I understand the white lines are not in movement, only the the black gaps at them and the lower ufo are in motion, is like that?. I have read this link you gave me, but I don't see it explained or don't have understand it.

Pleace, say it to me because I can't get out of my head the light duality between a particle and a wave joke fitting in my head to resolve all the duplicated and mixed images I see, even if I can't underestand it well :lol: . I have to take a rest of this :D .

Thanks for your responses and your time.

mynm
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Joined: 23 May 2015, 06:36

Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by mynm » 20 Nov 2021, 12:49

I have done another video. This is the video. I have put one green ufo in one frame a red one at the next and then 4 black frames in cicles.

Do you remember that with the LCD moving the head like saying no I didn't see the two colors. Now I see them, and blinking my eyes I also see them. Even with four black frames I still see the ufo blinking, how can it be happenig. Even my monitor back light is switched off some times as there is a black frame for a long time. How can be this happening?.

Also how your black insertion test are working and why you are seen a more vanished ufo with more black frames, if any pixel is on for many frames?. Maybe because you are seen a wave and it is vanished with the time?.

So it seems for my videos could be working like this:

Frame 1, Light emitter one ufo whit green color.

Light emitter one turns off.

Frame 2, Light emitter two ufo with a red color.

Light emitter two turns off.

If the cicle is repeated you will see a mix of the two colors as the colors of the waves are mixed because one light emitter is on, so even moving your head like saying no or blinking your eyes, because as you are seen one of the light emitter the light is acting like a particle and you see the color of the turned on light emirer and the wave of the turned off light emiter.

If you put four frames, the light emitters are off, so as the light is like a wave you can see waves of the two colors at the ordes it were turned off, Edited: blinking your eyes or moving the head like saying no, if not you will see the mixed color.

So is like if a light emitter is on you see the light as a particle, but if it is of you see it like a wave.

And this could explain the blur, as the light emitter is off, but you still can see the wave of the previous frame.

As that the light can act like a wave or a paticle is a scientific fact, do you thing this is posible?. What is your explanation for this?. I am not saing is like this, I can't demonstrate it.

Edited: I have tested with 16 frames and the ufo is still there, when the back light is turned of I can't see the ufo. I don't understand could the back light or the monitor doing it?. I will test this whit the CRT.

Edited: I see the same whit the CRT. I can explain this. Can you explain this?. Sorry for doing weird conjectures, but if them fits and you don't gave me one you know is the right one. I will be doing that this although unwilling because I don't know if them could be right or no, so I have to ask.

Edited: At the 30 and 15 fps the frames ar repeated but at lower fps are not, I was thinkg that the trepeticion of the frames coud be that you are seen a wave but it seens like is not like that for lower fps so I don't know. Maybe to see a light wave you need a light emisor near that you can chase. I don't know I don't know why I am doing this sorry. I am goin to strop now.

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Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by Chief Blur Buster » 21 Nov 2021, 15:03

I will answer the other questions later, but I want to answer one question at a time.
mynm wrote:
19 Nov 2021, 15:05
Yes it have PWM dimming, but I remember to read at a review that at 100 % brightness it don't have it. So with it at 100% I didn't see the multiple image, and moving the hands in front of it I see a complete train between the fingers and at 30 fps line I still see a double ufo. The right one is more dark than the left one. Is maybe a lack of response what is making it to be seen?
If you're talking about www.testufo.com and www.testufo.com/ghosting instead of black frames, that's simply GtG asymmetry effect.

LCD pixel response is different in one direction than the other direction (e.g. cyan->yellow may be slower than yellow->cyan GtG transition, as an example.

Pure MPRT(100%) is always perfectly symmetric. Pixel response effects causes ghosting or coronas (asymmetric ghosting effects).

Image

When you view www.testufo.com/ghosting on an LCD, you will often see more smearing on one side than the other. That's because of GtG effects. (pure MPRT is always symmetric blur that is limited to only one frametime's worth / refresh cycle's worth).

Discorz in the other thread ( viewtopic.php?f=19&p=74174#p74174 ) made a fantastic post about GtG blur and MPRT blur and how they combine:

column 1. 240Hz ,2. 144Hz, 3. 60Hz
ImageImageImage - Reference
ImageImageImage - MPRT + instant GtG
ImageImageImage - MPRT + slow GtG
Simulation, one pixel wide line panning left-right, transition 63-255-63, no OD, speed ∼960pps


column 1. 240Hz ,2. 144Hz, 3. 60Hz
ImageImageImage - Reference 32px wide line RGB 146
ImageImageImage - MPRT + instant GtG
ImageImageImage - MPRT + slow GtG
Gamma 2.2

TL;DR: Asymmetric blur = caused by GtG pixel response being slower/faster for opposite pixel color transitions

Please try not to confuse this kind of blur with other science.

It's important not to guess/speculate, the rest of your post will lead to an incorrect mental conclusion. However, I will answer one major question at a time, so I will respond to your other question at one answer. I do not believe you are ready to learn about color mixing effects yet. Please bear with me and try not to ask any additional questions yet (unless you want to delete earlier questions to replace with better questions).
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mynm
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Joined: 23 May 2015, 06:36

Re: Software BFI Double Image Effect! (Emulation of CRT 30fps @ 60Hz)

Post by mynm » 21 Nov 2021, 16:31

Chief Blur Buster wrote:
21 Nov 2021, 15:03
Ok this can explain the frame mixing at LCDsm, that is a thing I am saing. But I can see the same frame mixing at the CRT and it don't have ghosting or blur.
Chief Blur Buster wrote:
21 Nov 2021, 15:03

Please try not to confuse this kind of blur with other science.

It's important not to guess/speculate, the rest of your post will lead to an incorrect mental conclusion. However, I will answer one major question at a time, so I will respond to your other question at one answer. I do not believe you are ready to learn about color mixing effects yet. Please bear with me and try not to ask any additional questions yet (unless you want to delete earlier questions to replace with better questions).
I can guess or speculate what I want if I say that I am not an expert on that topic and I am not saying that is like that. And I say an expert have to say that it could be true or not. I was specting your answer about it as an expert. I don't know about physics, I only have seen some videos about that experiment and your tests are looking similar to a double slide experiment and what you say is blur looks like a wave at the CRT. I don't know if you know about physics, if you don't know, I think that could be interesting to tall about this with one.

Also your test, all the ufos are of the same color. I thing that this could be giving you erros in your conclusions. If do your blur test again with the ufos with different colors, maybe what you thing is blur could be the previous frame. I can test it as I don't have a lab and I can't know why is it happenig. I am not saying is like that, I only say that is what I think is happening and that maybe you could get a differnt conclusion testing it again like I say.

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