[crazygringo]

But why would the flicker be considered "excellent motion quality"?

In real life, there's no flicker. Motion blur is part of real life. Filmmakers use the 180-degree shutter rule as a default to intentionally capture the amount of motion blur that feels natural.

I can understand why the CRT would reduce the motion blur, in the same way that when I super-dim an LED lamp at night and wave my hand, I see a strobe effect instead of smooth motion, because the LED is actually flickering on and off.

But I don't understand why this would ever be desirable. I view it as a defect of dimmed LED lights at night, and I view it as an undesirable quality of CRT's. I don't understand why anyone would call that "excellent motion quality" as opposed to "undesirable strobe effect".

Or for another analogy, it's like how in war and action scenes in films they'll occasionally switch to a 90-degree shutter (or something less than 180) to reduce the motion blur to give a kind of hyper-real sensation. It's effective when used judiciously for a few shots, but you'd never want to watch a whole movie like that.

[CarVac]

Sample-and-hold causes smearing when your eyes track an image that is moving across the screen. That doesn't happen in the real world: if you follow an object with your eyes it is seen sharply.

With strobing, moving objects still remain sharp when tracked.

[mrob]

You're correct, but sadly most games and movies are made with low frame rates. Even 120fps is low compared to what you need for truly realistic motion. Flicker is a workaround to mitigate this problem. The ideal solution would be 1000fps or higher on a sample-and-hold display.

[crazygringo]

> Flicker is a workaround to mitigate this problem.

Isn't motion blur the best workaround to mitigate this problem?

As long as we're dealing with low frame rates, the motion blur in movies looks entirely natural. The lack of motion blur in a flicker situation looks extremely unnatural.

Which is why a lot of 3D games intentionally try to simulate motion blur.

And even if you're emulating an old 2D game designed for CRT's, I don't see why you'd prefer flicker over sample-and-hold. The link you provided explains how sample-and-hold "causes the frame to be blurred across your retinas" -- but this seems entirely desirable to me, since that's what happens with real objects in normal light. We expect motion blur. Real objects don't strobe/flicker.

(I mean, I can get you might want flicker for historical CRT authenticity, but I don't see how it could be a desirable property of displays generally.)

[mrob]

>Isn't motion blur the best workaround to mitigate this problem?

Motion blur in real life reacts to eye movement. When you watch a smoothly moving object, your eye accurately tracks it ("smooth pursuit") so that the image of that object is stationary on your retina, eliminating motion blur. If there are multiple objects moving in different directions you can only track one of them. You can choose where you want the motion blur just by focusing your attention. If you bake the motion blur into the video you loose this ability.

[crazygringo]

I guess it just comes down to aesthetic preference then.

If there's motion blur on something I'm tracking in smooth pursuit, it doesn't seem particularly objectionable. (I guess I also wonder how accurate the eye's smooth pursuit is -- especially with fast objects in video games, surely it's only approximate and therefore always somewhat blurry anyways? And even if you're tracking an object's movement perfectly, it can be still be blurry as the video game character's arms move, its legs shift, its torso rotates, etc.)

Whereas if there's a flicker/strobe effect, that feels far more objectionable to me.

At the end of the day, my eyes are used to motion blur so a little bit extra on an object my eye is tracking doesn't seem like a big deal -- it still feels natural. Whereas strobe/flicker seems like a huge deal -- extremely unnatural, jumpy and jittery.