Actuation point, and tactile bump activation (MX blues, greens, browns etc).

[falkentyne]

There has been a LONG standing rumor that cherry MX blue and green switches have the actuation point when pressing down DIFFERENT from the release point when pressing up.
According to this guide:

"Actuation Point is the point at which the contact mechanism registers a key press."
http://www.daskeyboard.com/blog/mechanical-keyboard-guide/

The actuation point is NOT the same as the tactile bump point, and in MOST keyboards, the actuation point occurs BELOW the tactile bump (click), not on top of it!
The bump does not correspond to where the switch registers a keypress!  Usually the bump is right above the actuation point, and that goes for both press and release.

I did some tests with MX greens and blues, and the distance/point at which the switch registers a key press or releases the press is the EXACT SAME on both keys!
You can test it here.
http://www.microsoft.com/appliedsciences/AntiGhostingExplained.mspx

There is absolutely NO difference in where the switch actuates or releases the key!
The difference is where the BUMP itself is activated (and clicks for clicky switches) and is released!
On MX browns, this point is at the same position on the switch going from activation to release.
On blues and greens, the activation is lower than the release of the switch.

This does NOT affect the actuation!
So there is no problem double tapping on blues and green MX switches!
The only problem is if you use muscle memory and try to time the bump itself.
For people who bottom out, no issues.

[tp4tissue]

Well,

Since NOTHING actually relies on Double Tapping..

Very few games are even dependent on "PRECISE" keyboard inputs..



Hysteresis..   Yea, it's there..   Does it matter no..

[Oobly]

There has been a LONG standing rumor that cherry MX blue and green switches have the actuation point when pressing down DIFFERENT from the release point when pressing up.
According to this guide:

"Actuation Point is the point at which the contact mechanism registers a key press."
http://www.daskeyboard.com/blog/mechanical-keyboard-guide/

The actuation point is NOT the same as the tactile bump point, and in MOST keyboards, the actuation point occurs BELOW the tactile bump (click), not on top of it!
The bump does not correspond to where the switch registers a keypress!  Usually the bump is right above the actuation point, and that goes for both press and release.

I did some tests with MX greens and blues, and the distance/point at which the switch registers a key press or releases the press is the EXACT SAME on both keys!
You can test it here.
http://www.microsoft.com/appliedsciences/AntiGhostingExplained.mspx

There is absolutely NO difference in where the switch actuates or releases the key!
The difference is where the BUMP itself is activated (and clicks for clicky switches) and is released!
On MX browns, this point is at the same position on the switch going from activation to release.
On blues and greens, the activation is lower than the release of the switch.

This does NOT affect the actuation!
So there is no problem double tapping on blues and green MX switches!
The only problem is if you use muscle memory and try to time the bump itself.
For people who bottom out, no issues.

I understand what you're getting at, the switch actuates when you've gone over the bump since the moving part then moves down independently of the main slider part, causing actuation.

HOWEVER, you still have to raise the main slider higher than you press it to actuate in order to "reset" the moving part since it has to go over the bump on both directions to get to the correct horizontal displacement point (which is independent of the bump itself but is always the same point on the moving part of the slider) and the bump is now lower.

This is called hysteresis and means you have to raise the slider higher than other switches in order to get it to release so you can actuate it again for a double-tap. Means you have to raise the slider higher on the clicky switches than all the other MX types. You can't "test" this by hand very easily since going over the bump causes the resistance to drop, but even if you do it very slowly and stop moving the slider when it actuates, you still have to raise it from that point to release it, more than you do on tactile and linear switches, due to the part of the moving slider piece that corresponds to the correct horizontal displacement of the leaf now being lower on the upstroke than it was on the downstroke. You can get them to release and re-actuate by hovering around that point VERY closely, but it's MUCH harder to do than on other types due to the moving part resetting if you raise it too much (and then you have to press down further again to get it to actuate) and it's very hard to "find" this point when you're trying to do a rapid double-tap, whereas on a linear or tactile it doesn't matter how high you raise it before pressing again.

So, it still requires more movement and more time than tactiles and linears unless you have robot fingers.

@tp: Really? Are you aware that you actually double-tapped 8 times in your post? Does it matter to you? Maybe not. Does it matter to others. Definitely. I know of a number of people who even find it difficult to type on Blues when a double letter is required due to the hysteresis. Of course, they're used to other either linear or tactiles, so they may get used to it if they practice, but why bother? No point in making yourself do more work if you're already being more efficient on a different switch type. And efficiency and speed are not necessarily the same thing. Efficient slower typing can allow you to type for longer with less fatigue.

[KHAANNN]

I personally liked hysteresis a bit, on reds I sometimes double tap the space by mistake, hysteresis never bothered me on greens, it also seems to me that hysteresis prevents most of the electrical debounce / false-double-registry issues, which seems like a plus

None of these are really issues if you bottom out like crazy, that's probably why it didn't bother me

[falkentyne]

Yeah I always bottom out.  I don't even know how you can game on a keyboard without bottoming out or coming close to it.  After all, you're holding down forward (or strafe) anyway.  Now, typing, on the other hand, that I can understand, since you don't want to bottom out while typing.  Depending on what's best for you, you may get higher WPM by not bottoming out, but on a light switch like a MX brown, it's hard to avoid.

But yes your explanation about the elevation of click/reset makes sense.  But now now that I've used MX reds (the dead blue LED K70 vengeance), mx Browns (Ducky 3/4) and MX greens (ducky fire 69), this "hysteresis" thing definitely doesn't affect me.

And MX greens are just so much more fun to game on than Browns..I guess a keyboard with feedback is like a woman with feedback...it feels good, you know?
(And with MX blues on the shift key and space, that's why I think the Ducky shine 69 fire is the best keyboard ever created besides the old IBM model "F" with hardware NKRO....

Any keyboards exist with tactile greys?

[KHAANNN]

Haven't seen one, yet you can always get the switches and either re-solder them onto an existing board or buy a fresh pcb set etc. to solder them onto

I also loved the Green's, yet sound/ping issues reverted me to Red's, tactile/sound feedback is great, yet when it's bloated by after-effects, it's just disturbing beyond imagination for me

It should be either click+thock, or click+clack+thock, clack being the bottom out and thock being the reset plastic sound

Yet with green's it's: click+clack+thochk+spring ping+plate resonation, too much sound to process, caused headache's after some time

Enjoying my o-ring clack + thock on my red's now, the plate resonation is also mellow like a piano string resonation, instead of a drum bell like the Green's (it's hard to find a plate/keyboard that can handle Green bottom-out's)

When you experience these issues, actuation/activation point issues seem extremely unimportant

----

Yet, if you're a 10-finger touch typist, activation issues might be important, as you won't bottom out and always experience the switches on their best zones
I tried 10 finger home-row typing a while ago, a lot of things made sense after that, I also appreciated my own typing method a lot, which it mostly 2-fingers + thumbs