5 ms·

The video still shows a lot of lag between when the stylus touches the glass and the pixels in the app show the pen trail. This needs to be heavily optimized or

The video still shows a lot of lag between when the stylus touches the glass and the pixels in the app show the pen trail. This needs to be heavily optimized or else it will make their hardware a lot of engineering work for nothing and users won't be happy. At this stage, from the video, it looks to have similar latency as other existing iPad sketch apps and those have no hardware dongle or stylus (and cost $100 less.)

revelation 14y ago
There is no way to optimize it as the matter is out of their hand. Its just the delay for input events to go from hardware to kernel to user land. MS Research had a neat demo on this very topic some time ago. Edit: never mind, it seems they use their own hardware. In that case, it would be interesting to know if iOS allows fast raw access to the external periphery.
- garindra 14y ago
  This is the demo video you're talking about : http://www.youtube.com/watch?v=vOvQCPLkPt4 http://www.youtube.com/watch?v=vOvQCPLkPt4
  - artursapek 14y ago
    Ah yes, I remember this. Worth noting that his device is a projector putting the image on a screen, and I think it's got a lot more computing power behind it than an iPad has available.
    - Lerc 14y ago
      The current latency isn't a CPU issue though. I'm not sure of the refresh rate of the iPad (60Hz?) but the hardware has no trouble updating the display in a single frame. It should be noted that unless Microsoft had a 1000Hz display running, there was something fishy going on with their 1ms update.
      - chadv 14y ago
        It's a custom display purpose built for this demo. I believe that it is 1000Hz.
      - owenfi 14y ago
        From this high speed video I took I think the refresh rate is 60Hz (this shows it is at least 60). http://owenimholte.wordpress.com/2012/03/30/ipad-3-screen-refresh-example/ http://owenimholte.wordpress.com/2012/03/30/ipad-3-screen-re...
- kenrikm 14y ago
  Lag = fail. Interesting since it seems they use the dock connector so you would assume that there would be minimal lag compared to say Bluetooth.
  - rob_colluding 14y ago
    From Collusion: Hi All just in case didn't catch my reply, I'd like to direct your attention to what i posted elsewhere on hacker news: Paraphrased from our Kickstarter page: Thanks to those that have identified an issue with our drawing video clips, they were shot with a high fps camera and included in our video at HALF SPEED. In response, our video will be adjusted to demonstrate the drawing at normal speed. Additionally, we have identified areas to further optimize our algorithms for you to ensure that any latency is fully minimized. You can consider drawing speed to be equivalent experience to the iPad touch interface; if not better. Cheers, Rob (CEO) Collusion By the way we are now 'de lurking' as we have finally got some sleep after the marathon lead-up to the kickstarter launch - 53 hours and no kip is not pleasant! Feel free to ask us questions directly. There is a LOT of work going into Collusion to address many of the existing fundamental issues of pen on tablet computing (many raised right here on hacker news inc latency, accuracy, palm rejection etc) we kindly ask you do this before reaching for the nearest pitchfork:) Talk to us.
mrtron 14y ago
I believe the hardware limit on iPads is still pretty shitty compared to some next gen touchscreens. It is already likely reasonably optimized.
slantyyz 14y ago
It's a neat idea, but the lag is a dealbreaker for me. I've been looking/waiting for a pen based note-taking solution, even if it's a unitasking solution, to get rid of the heavy hardcover sketchbook in my briefcase. My use case is simple, I just want a digital copy of my notes -- I don't need any OCR or anything fancy like that, and I'm not convinced that a LiveScribe is the way to go. I had high hopes for the NoteSlate, but that product has turned out to be vapor ware.
- learc83 14y ago
  Have you seen the wacom inkling? http://www.wacom.com/en/products/inkling.aspx http://www.wacom.com/en/products/inkling.aspx
  - slantyyz 14y ago
    The Inkling looks interesting. The Verge gave it a 6.8, which isn't too too reassuring. The thing with the smart pens is that they're chunkier than I'm used to, and then I worry about the smoothness of the pens. I know the LiveScribe doesn't have gel based ink refills, which is basically the only type of pen I write with. I find the friction from normal ball point pens a little uncomfortable.
    - Centigonal 14y ago
      You should honestly consider purchasing a fountain pen. They work via capillary action, which means that they write on contact -- no pressure needed. At all. Some good starters are the LAMY Safari, the TWSBI 540, and the Kaweco Sport. All of these cost <$50 and can take bottled ink (with possible modifications to the Kaweco), reducing refill costs drastically. I, too, used to think gel pens were the bomb, but writing with a fountain pen is just something else. :D
      - slantyyz 14y ago
        That's very informative, I think I'll give a fountain pen a shot.
nirmal 14y ago
I asked about the lag and they responded with this tweet. https://mobile.twitter.com/#!/collusionapp/status/208366845781221377 https://mobile.twitter.com/#!/collusionapp/status/2083668457...
- ricardobeat 14y ago
  > due to high-speed filming The laggy footage starting at 0:28 looks like real-time to me. You can see the crosshair falling behind at 0:35 too, and that's clearly normal speed unless the guy can do handwriting in slow-motion. And I can't think of any way a high framerate would affect the perception of lag when played in realtime.
- jurre 14y ago
  https://twitter.com/collusionapp/status/208366845781221377 https://twitter.com/collusionapp/status/208366845781221377 for those not on a mobile phone (it was asking me to log in on the mobile subdomain but I'm already logged in on my laptop)
  - alter8 14y ago
    The hashbang is the problem, just removing it also does the trick: http://mobile.twitter.com/collusionapp/status/208366845781221377 http://mobile.twitter.com/collusionapp/status/20836684578122...
lukejohnnuttall 14y ago
When I tried it last night, the guys said that the lag is due to iOS framework stuff, but they have an open gl version in the works which fixes it
LaSombra 14y ago
I have an iPad 3 with Paper, Penultimate and Inkflow (my personal favorite) and they are all laggy using a finger or a stylus, so, maybe, the lag comes from the iPad 3 with Retina display?
rob_colluding 14y ago
erm, that might be because your still looking at the current video. New video to be uploaded in the morning, have a look then:)

revelation 14y ago

There is no way to optimize it as the matter is out of their hand. Its just the delay for input events to go from hardware to kernel to user land. MS Research had a neat demo on this very topic some time ago. Edit: never mind, it seems they use their own hardware. In that case, it would be interesting to know if iOS allows fast raw access to the external periphery.

garindra 14y ago
This is the demo video you're talking about : http://www.youtube.com/watch?v=vOvQCPLkPt4 http://www.youtube.com/watch?v=vOvQCPLkPt4
- artursapek 14y ago
  Ah yes, I remember this. Worth noting that his device is a projector putting the image on a screen, and I think it's got a lot more computing power behind it than an iPad has available.
  - Lerc 14y ago
    The current latency isn't a CPU issue though. I'm not sure of the refresh rate of the iPad (60Hz?) but the hardware has no trouble updating the display in a single frame. It should be noted that unless Microsoft had a 1000Hz display running, there was something fishy going on with their 1ms update.
    - chadv 14y ago
      It's a custom display purpose built for this demo. I believe that it is 1000Hz.
    - owenfi 14y ago
      From this high speed video I took I think the refresh rate is 60Hz (this shows it is at least 60). http://owenimholte.wordpress.com/2012/03/30/ipad-3-screen-refresh-example/ http://owenimholte.wordpress.com/2012/03/30/ipad-3-screen-re...
kenrikm 14y ago
Lag = fail. Interesting since it seems they use the dock connector so you would assume that there would be minimal lag compared to say Bluetooth.
- rob_colluding 14y ago
  From Collusion: Hi All just in case didn't catch my reply, I'd like to direct your attention to what i posted elsewhere on hacker news: Paraphrased from our Kickstarter page: Thanks to those that have identified an issue with our drawing video clips, they were shot with a high fps camera and included in our video at HALF SPEED. In response, our video will be adjusted to demonstrate the drawing at normal speed. Additionally, we have identified areas to further optimize our algorithms for you to ensure that any latency is fully minimized. You can consider drawing speed to be equivalent experience to the iPad touch interface; if not better. Cheers, Rob (CEO) Collusion By the way we are now 'de lurking' as we have finally got some sleep after the marathon lead-up to the kickstarter launch - 53 hours and no kip is not pleasant! Feel free to ask us questions directly. There is a LOT of work going into Collusion to address many of the existing fundamental issues of pen on tablet computing (many raised right here on hacker news inc latency, accuracy, palm rejection etc) we kindly ask you do this before reaching for the nearest pitchfork:) Talk to us.

mrtron 14y ago

I believe the hardware limit on iPads is still pretty shitty compared to some next gen touchscreens. It is already likely reasonably optimized.

slantyyz 14y ago

It's a neat idea, but the lag is a dealbreaker for me. I've been looking/waiting for a pen based note-taking solution, even if it's a unitasking solution, to get rid of the heavy hardcover sketchbook in my briefcase. My use case is simple, I just want a digital copy of my notes -- I don't need any OCR or anything fancy like that, and I'm not convinced that a LiveScribe is the way to go. I had high hopes for the NoteSlate, but that product has turned out to be vapor ware.

learc83 14y ago
Have you seen the wacom inkling? http://www.wacom.com/en/products/inkling.aspx http://www.wacom.com/en/products/inkling.aspx
- slantyyz 14y ago
  The Inkling looks interesting. The Verge gave it a 6.8, which isn't too too reassuring. The thing with the smart pens is that they're chunkier than I'm used to, and then I worry about the smoothness of the pens. I know the LiveScribe doesn't have gel based ink refills, which is basically the only type of pen I write with. I find the friction from normal ball point pens a little uncomfortable.
  - Centigonal 14y ago
    You should honestly consider purchasing a fountain pen. They work via capillary action, which means that they write on contact -- no pressure needed. At all. Some good starters are the LAMY Safari, the TWSBI 540, and the Kaweco Sport. All of these cost <$50 and can take bottled ink (with possible modifications to the Kaweco), reducing refill costs drastically. I, too, used to think gel pens were the bomb, but writing with a fountain pen is just something else. :D
    - slantyyz 14y ago
      That's very informative, I think I'll give a fountain pen a shot.

nirmal 14y ago

I asked about the lag and they responded with this tweet. https://mobile.twitter.com/#!/collusionapp/status/208366845781221377 https://mobile.twitter.com/#!/collusionapp/status/2083668457...

ricardobeat 14y ago
> due to high-speed filming The laggy footage starting at 0:28 looks like real-time to me. You can see the crosshair falling behind at 0:35 too, and that's clearly normal speed unless the guy can do handwriting in slow-motion. And I can't think of any way a high framerate would affect the perception of lag when played in realtime.
jurre 14y ago
https://twitter.com/collusionapp/status/208366845781221377 https://twitter.com/collusionapp/status/208366845781221377 for those not on a mobile phone (it was asking me to log in on the mobile subdomain but I'm already logged in on my laptop)
- alter8 14y ago
  The hashbang is the problem, just removing it also does the trick: http://mobile.twitter.com/collusionapp/status/208366845781221377 http://mobile.twitter.com/collusionapp/status/20836684578122...

lukejohnnuttall 14y ago

When I tried it last night, the guys said that the lag is due to iOS framework stuff, but they have an open gl version in the works which fixes it

LaSombra 14y ago

I have an iPad 3 with Paper, Penultimate and Inkflow (my personal favorite) and they are all laggy using a finger or a stylus, so, maybe, the lag comes from the iPad 3 with Retina display?

rob_colluding 14y ago

erm, that might be because your still looking at the current video. New video to be uploaded in the morning, have a look then:)