500ms is a LOOONG time. That's about how long my S8 needs, and I always question whether it works this time. 100ms or so would be great.

Looked like it was reasonably quick in the demo.

I may be wrong, but I remember reading something that most humans can't notice any lag below 200ms.

200ms is five frames/changes per second, and is definitely very noticeable. You may be thinking of a figure closer to about 12ms or so, which is the approximate threshold of perception for audio lag.

iPhone X's front camera shoots at 60fps

You can notice sub-200ms lag, but for when you aren't specifically watching for lag or firing a series of rapid events one-after-another, sub-200ms seems to be roughly the point where it "feels instantaneous."

In my experience a little under 100ms "feels" instantaneous.

Definitely noticeable in gaming, 200ms is unplayable.

Depends on how the game is tuned to handle it. Somehow we all played Quake / UT back in the day with that kind of ping.

FaceID with lag compensation! As soon as it sees a face it starts to unlock based on a fast prediction, then if the authoritative secure side of the chip says "No, authentication actually failed" it rolls back the clock and relocks itself!

200ms can refer to network latency, input latency, frame render time, etc.

That's absolutely not true. I can tell the difference between 60 hz (16ms) and my 144 hz monitor. I can tell when my 144 hz monitor is accidentally running at a lower refresh rate, including 120, 100, 75, and 60.

200 ms is like a full react/response time for a human to take action in response to input, our actual sense of time is much finer than what our nervous system can make our muscles do.

That's not lag though, that's refresh rate.

The question is could you tell the difference between your 144hz monitor and your 144hz monitor with the signal delayed 100ms.

Good monitor reviews include a test of the delay. 3 frames delay (<100 ms at 60hz) is absolutely atrocious and easily detected by players in games.

But of course, that's not the problem. It's ok that the phone doesn't unlock with out me noticing the delay. It just can't be so long that I start doubting whether it works.

I notice a 1 frame in 60hz delay (<17ms) when comparing vsync on vs. gsync @ 57 fps. I'm sure many other video gamers will as well.

Yes. You'd feel quite drunk even controlling the mouse pointer with 100ms lag. This was/is actually a problem with some LCDs (VA in particular) that cached a frame or two in order to "anticipate" future changes so that they could adjust the voltage and make the image transition faster.

This overdrive is probably also the cause of burn-in-effects that seems to be especially common in VA panels.

I think almost everyone playing games could.

Is that because of the faster refresh rate, or because none of those divide evenly into 144 and thus you're getting weird frame stretching?

Curious as I just got back into gaming after several years and everyone seems to love 144fps now, wondering if I should upgrade. I have a 1080Ti, so I could presumably render that

G-sync my dude. No frame stretching/sync tears.

Ah, I was just wondering if running a 144hz monitor at 60hz was like watching a 24fps movie at 30fps... if that makes sense? But the monitor can just switch its actual refresh rate.

Yeah, it'll really trick.

Upgraded to a 165hz G-Sync panel recently and it was a revelation after running at a v-synced 60hz for years and years.

Order the 1080TI about a week later as the 970 I had wasn't cutting it at 1440p.

If you've got a 1080TI you likely don't need gsync - it's only really useful when you're running slower than native refresh rate.

When native is 165hz...

I actually find most modern games run at about 90-110fps with what I would consider "good settings".

Even if you turn settings way down 165 is really hard to maintain.

Agreed. If it's fast enough to unlock by the time my face is facing the iPhone, then I'm not losing any productivity there.

e: But watching the keynote, it's definitely doesn't seem that fast...

I disagree.

First off, as the person above said, you can start the unlocking process long before it's even facing with with touch-id, as you're taking it out of your pocket. With this, this "timer" starts only when it's fully out and facing you.

Next up, in this, it has to be facing you perfectly. You can't unlock it sneakily under the table, you can't do it while someone else is looking at your phone, etc.

Lastly, you still need to manually swipe to actually open the phone, so it's not like you're not using your finger either. If at least you could unlock it without using your hands that would be something.

At the end of the day, I still want to see properly reviews of what the actual successrate is too. It's not all about speed, if it fails 5% of the time, that's extremely annoying.

That's probably why they make you swipe up. The gesture takes 500 ms at least, and it only has to unlock by the end of it.

it looked pretty slow on the demo. In the order of 1500ms.

TouchID is much faster.

The unlock itself actually looked pretty fast... it just seemed a bit awkward that it had to be paired with a swipe to unlock.

That matches what they did to touch ID in iOS 10: unlocking no longer actually took you to the home screen, just left you on the lock screen with your phone unlocked for... some... reason. There is a setting to change it, maybe there will be one for this as well.

One of the reasons was that on newer phones (the 6S and the 7) Touch ID was so fast that it was hard to even see the lock screen. If you use the home button to wake up the phone then you would be authenticated and the screen would go away before you had a chance to see anything.

Their solution was to split it into two different steps.

You have the same issue with Face ID. If the "lock screen" went away as soon as you look at your phone you could never actually look at the notifications there.

Clearly they had to do something. Does this work well? I guess we'll find out when the reviews come out.

No, the issue is different. With FaceID, if there was no swipe, your phone would unlock all the time for no reason at all. For example while driving, or while having it flat on your desk and hovering near it, and so on.

I am very skeptical about FaceID. I actually love TouchID, can hardly imagine anything better, but Apple has surprised us before.

Yes! Imagine you just wanted to glance at your notifications. So you wake your phone and... it goes straight through to the home screen, darn it!

Oh yeah, I forgot that I had to change that setting. I definitely hope it's the same with Face ID - I don't use home screen notifications for anything.

True, it's three things:

- attention - faceid - swipe

And no cue to know if faceid worked before swiping. I couldn't see cues (maybe I missed them).

Except for that large padlock icon that shows the unlocked state when Face ID has identified you?

Aight, I failed, but it's really not how I like such information conveyed.

Agreed. I'd want the phone to look "more asleep" when locked, e.g. a dimmed or vignetted background photo which would pop to life when unlocked.

Something that "pop" yes. A border flash, a hint at the bottom that means "you can swipe now". The [un]lock icon can stay but it's to high focus to be a good UI.

To be honest, with the full glass, I expected something like.. a full screen fingerprint scanner (have no idea if it's feasible at all). I thing TouchID is the best biometric input for casual operation.

But then you'd never be able to look at your notifications without "unlocking" the phone. That doesn't seem too useful.

Adding a clearer visual cue for unlock would have no impact one way or the other here.

Sorry, I read your first response as the screen being dimmer, not the wallpaper. I was complaining that you wouldn't be able to read notifications if the screen was dimmed but that wasn't what you said. My bad!

A padlock icon in the corner unlocks when Face ID has authenticated.

top center of the lock screen

TouchID always takes a "slightly-perceptible" amount of time to work, so any improvement over that would be fine with me.

What about unlocking without looking at it ?

I'm guessing you can tap on the padlock to enter your passcode.

that requires paying attention (and probably looking at it, even if you know the location, a screen is too flat), unlike the home button.

gone away.

Especially if you have several banking or investment related apps that use touch-id.