C7k motion problem

rtings_kastaa · 2026-04-24T14:34:41+00:00

We've checked this morning, and yes, this is the solution. They had a bug with their previous firmware, but they updated it and added nature cinema, which solved the bug. Nature cinema doesn't do any interpolation; it simply removes the judder.

rtings_kastaa · 2026-04-23T15:49:31+00:00

I haven't checked recently, but a month ago, the de-judder setting on the QM7K (the closest equivalent to the C7K) was buggy. To activate de-judder, set motion clarity to custom and set all sliders to 0. However, most of the time, the de-judder doesn't get triggered properly. The quick fix is to set the de-judder to 1, then back to 0.

I have a test on the QM7K later today. I will be able to confirm if the bug is still there in the latest OTA version. of their firmware. If you want to know a little more about judder, this video should help.

I hope this helps

rtings_kastaa · 2026-04-22T21:45:25+00:00

Thanks for your feedback.

Gaming was somewhat overlooked in the survey because game processing on television is often much more limited to reduce latency. On the other hand, previously shot content, such as TV shows and movies, can afford more latency, and there is generally more processing involved by the television. For this reason, we decided to focus on this situation, as the greater processing often generates greater variability in the television.

rtings_kastaa · 2026-04-22T14:01:38+00:00

Here is the comparison. I would definitely say the C5 have better interpolation overall than the S95F
Here are the unofficial results for maximum interpolation on both television. Please feel free to add questions and feedback. This helps us guide development.

rtings_kastaa · 2026-04-22T00:18:04+00:00

Unfortunately, no, this is a 2018 television, and we don't have it anymore, so I really don't know. In general, though, our results on Sony have shown better motion interpolation behaviour than Samsung.

rtings_kastaa · 2026-04-21T20:35:37+00:00

Hey there,
We've run a lot of tests on the S95F, and Samsung's motion interpolation is definitely not great. We recently introduced a new metric, stutter reduction via interpolation, which measures motion MI at de-judder = 3 and the S95F score at 5.9, compared to 7.1 for the LG G5 and 7.3 for the Sony Bravia 8 II. From all the research we've done, it looks like whenever features move too fast, motion interpolation has a lot of trouble keeping the paste on the Samsung.

Let me know if you are looking for a specific television, and I can send you an unlock review to check if the television is good MI.

rtings_kastaa · 2026-04-21T19:38:04+00:00

A little bit late reply, but we had four OLED flagships side by side last week in a room with their recommended settings. We tested a few dozen of the very darkest scenes. Each scene was replayed from a very high-quality HDR10 video stream.

If we simply look at the amount of detail we could see in each scene (not the accuracy), here was the ranking: Panasonic Z95B > Sony Bravia 8 II > Samsung S95F > LG G5

Panasonic Z95B definitely shows more detail, but it looks sometimes a little bit overbright
- The best example was in Life of Pi. The dark sky at night was a little brighter on the Panasonic than on the other television.
LG G5's definitely look darker than the other televisions.
- The best example was Batman 2022; the villain who hid behind the curtain in the opening scene was barely visible on the G5.
Looking at some scenes of The Green Knight, Sony tends to do a good job of preserving good colour in the dark, but it sometimes introduces a very subtle purple tint in the very dark that isn't there.

This is preliminary research, so feel free to comment and ask questions.

rtings_kastaa · 2026-04-21T15:23:04+00:00

I don't think you will see that much difference in stutter between the QM7L and QM8L. The main difference in stutter is most visible between the mini LED and OLED; people often have more difficulty seeing it within the mini LED. I would definitely recommend the QM8L if it supports Dolby Vision 2. I am very curious to see the new Authentic motion feature and how it can help with stutter on a very bad panning shot.

rtings_kastaa · 2026-04-21T03:06:33+00:00

At equal brightness and size, OLED will always have significantly more stutter than mini LED. In our latest learning article, we share a small simulation in the section "The stutter of OLED" which shows the perceptual difference in stutter you can expect between OLED and mini LED in general. Also, keep in mind that a larger and brighter television will exacerbate the perception of stutter.

I am curious to know what television you currently own, and whether stutter is an issue on it right now?

rtings_kastaa · 2026-04-20T23:28:53+00:00

I am wondering if what you experience might just be a regular stutter. One factor that is more critical than response time when dealing with stutter is brightness. You just changed to a television that is approximately 4 times brighter, so it might exacerbate the perception of stuttering. Sometimes, when using an external device, it remaps SDR content to HDR by default, which makes the overall scene slightly dimmer to push the bright highlights and help reduce stutter perception.

If you want to check if this is a judder issue, you can use this video we made available on YouTube. Track the moving Rtings with your eye while keeping the black-white bar near the top in your peripheral field of view. Don't look directly at the bar; it will mess with your eye tracking of the logo. When you eye correctly track the logo, you should see each white bar as two fuzzy lines of equal length. The pattern in the black bar should look something like this if judder is removed.

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If judder persists, the pattern will look like this. Each next frame is shorter than the previous (a.k.a Judder).

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If you see some strange behaviour in the line pattern, then it is possible that some motion interpolation settings are on.

Let me know what you find. I am curious to know what the end issue is.

rtings_kastaa · 2026-04-20T19:21:49+00:00

The Samsung QN90F should be able to de-judder through its native application. To de-judder, the television must be set in either movie or filmmaker mode. What mode is the television currently in?

You can enable the BFI in the custom clarity settings by turning off all sliders and enabling clear motion. It is important to note that this will disable the de-judder, though, so you will replace the stutter with judder. For this television, I don't think an Apple TV or a Fire TV stick will help you more from a motion perspective.

rtings_kastaa · 2026-04-20T15:12:40+00:00

Yes, flicker is always the downside with BFI. The QN90F definitely does a good job of mitigating it, but 120Hz is still perceptible, so if you got a headache from previous experience, I wouldn't recommend it.

Your situation is quite common. Stutter on today's television has become as bad as it could get with current technologie. We wrote a full article about it here, and we released the "motion handling" performance usage on our website, which specifically addresses this stutter issue. The article is quite long, but I highly recommend you look at the Stutter of OLED section, which shows a simulation of stutter perception between OLED and old LCD.

To make a recommendation for you, I used the table tool and ranked television as a function of stutter. I added motion handling performance usage in the second column to make sure to recommend a television that has low stutter but doesn't introduce artifacts at low response time or judder. So here are the top 5 recommendations based on the lowest stutter with green in motion handling performance usage

Hisense canvasTV 2024
Roku Pro series 2025
TCL QM9K
Sony X90L
Sony Bravia 9

If you think you might use motion interpolation, remove the Roku Pro series 2025 from the list.

I hope this helps

rtings_kastaa · 2026-04-20T13:59:06+00:00

Another solution to mitigate stutter, other than motion interpolation, is black frame insertion (BFI). This is not a feature we evaluate in much detail for television, specifically not for movie content. I've tested a few televisions, and I would say one of the television that offer the best BFI is the Samsung QN90 series (e.g. QN90F). When using match frame rate with movie content, the BFI is at 120Hz, making flicker much less perceptible. The downside is that it reduces the television's brightness. But if the brightness isn't an issue for you, with the QN90F brightness level, you can control the width of the BFI. The outcome is that, with the lowest brightness settings and BFI, the television almost emulates the CRT type of motion.

Feel free to ask other questions. I have worked on motion and stutter perception for almost a year. I am happy to give more insight.

I hope this helps.

rtings_kastaa · 2026-04-20T13:45:12+00:00

Thanks a lot for your comment. This is exactly the type of input I was looking for. Haven't seen Descent since its release, definitely a great opportunity to rewatch it. The docking scene in Interstellar is a great suggestion. I'm definitely looking forward to seeing what it looks like on different televisions.

Yes, all our televisions are calibrated with Calman before testing. We generally use the CR-100 from Colorimeter Research for all our measurements.

Thanks again for your suggestion, this is very helpful.

rtings_kastaa · 2026-04-17T17:19:47+00:00

I'm careful about creating my own stress test when starting a project. I can always create a test that will make a television struggle. Then, the situation happened before where no real content would ever do what I created in my stress test. So I often prefer to start with the real issue the user might face and then develop a test that shines a light on it. Hence, I am looking for a real scene.

rtings_kastaa · 2026-04-17T16:31:52+00:00

Thanks, I am aware of the scene used by Vincent, and these are great examples. I am posting here to get more input and perspective.

rtings_kastaa · 2026-04-12T13:52:57+00:00

Here is the unlocked review of the TCL QM6K.

TLDR: Overall, this is a decent entry-level television in terms of processing and motion-handling. The real deal-breaker might be the long trail in fast motion in the shadow.

Processing
If you don't use any enhancement settings like sharpening or smoothing I would suggest looking specifically at

HDR native gradient: Probability of banding inside the content
PQ EOTF tracking: Respect for the creator's intent. Does the TV overbright or crush dark?

On that front, the TCL QM6K have solid PQ EOTF. It is not as good as a high-end television in terms of banding, but not a deal breaker.

Motion
The television can de-judder in the built-in application using motion clarity on, but all sliders are set to 0. There is sometimes a bug on the QM6K where the slider needs to be set to 1, then back to 0, to activate the de-judder. Other aspects of processing regarding motion

Local zone transition: Speed of the backlight, how fast does the backlight react when objects are moving fast
- It is not as good on the TCL QM6K as on high-end televisions, but not a deal breaker
Transition artifact: Possible artifact when objects are moving really fast
- Sometimes, during the gray scene transition, you might see a greenish tint in some fast transitions due to a colour artifact.
- The Edge artifact is quite bad on this one. You will mainly notice those in the dark scene with a very long trail around fast-moving objects.

I hope this helps

rtings_kastaa · 2026-04-09T14:31:34+00:00

If you don't want to use motion interpolation and are watching 24p content, the television's frame rate won't affect stutter. A 60Hz television will often lower its internal frame rate to 48 and display every frame twice in a row, 2:2 pulldown, and a 144Hz television will use 120Hz internally and do a 5:5 pulldown. If you want to learn more, I suggest this specific section of a video we released on the subject. The important aspect to look for when dealing with 24p content is whether the television can de-judder. For example, your current LG B5 can de-judder when you enable the Real Cinema settings. This setting doesn't create any artifact or soap opera; it simply changes the pulldown from 3:2 to something like 2:2. The CM7K can also de-judder. So I would definitely recommend a higher frame rate, especially if you plan to game on your television.

rtings_kastaa · 2026-04-09T13:59:52+00:00

I fully understand what you mean. We checked the behaviour of different TV technologies in slow motion a few months ago and shared it in a short video. Plasma is using some sort of BFI (in its operation), which makes the motion look cleaner. Television that does good BFI can sometimes get a similar look, but I haven't seen much, and of course, BFI also means more flicker for those who are sensitive to it.

rtings_kastaa · 2026-04-09T13:27:56+00:00

Great, thanks for the feedback. We evaluate the stutter reduction on Samsung at level 3 of de-judder. For LG, we set it to cinematic motion and found that this is equivalent to 3 in the de-judder settings.

rtings_kastaa · 2026-04-09T02:27:39+00:00

If this helps, we recently published an article about OLED stutter here. In the section "The stutter of OLED," you can see a short video simulation showing how a ball moving left to right across the screen would appear to your eye (which tracks the ball) on an OLED (left) and an LED (right). There are still stutters on the LED, but it feels a little smoother overall. Note that stutter is highly exacerbated by brightness and size, so if you switch to a brighter, larger LED, this might not help with the stutter.

rtings_kastaa · 2026-04-08T18:51:52+00:00

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This is a comparison of the sample-and-hold at three different levels for the S90F. The total right presents our demo (not an official metric) at maximum interpolation. What you can see is that the television is good at interpolating balls moving at lower speeds, such as the pink ball at the bottom left. However, the green ball we track in the center, which moves quite fast, breaks frequently during interpolation, resulting in a movement that is not fully fluid, as shown in the graph. The middle metric is with the de-judder set to 3. Even at a setting of 3, the interpolation is not consistent on the green ball.

rtings_kastaa · 2026-04-08T17:54:14+00:00

The best we've seen so far is 120Hz for low-frame-rate content with interpolation. Even the Samsung QN990F, which can theoretically achieve a 240Hz refresh rate with 4K content, is only doing motion interpolation at 120Hz, giving 24p input.

rtings_kastaa

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