Beamer Latency Measurement Topic
Posted: 03 November 2007 10:28 AM   [ Ignore ]
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A few weeks ago I already showed some images of latency issues with beamers (Digital Projectors).

My results:
3M DMS 700 (1024 x 768) - about 100ms
Canon LV-S1E (800 x 600) - less than 16.67ms

Because I could not find much information about latency of beamers in general (as far as I know, no manufacturer specifies this in the manual) I would like to ask if multi-touch enthausiasts could measure there own beamers. All you will need is a camera which is capable of setting the shutterspeed manual (it needs to be 1/60 sec). Please post your results in the comments section of my blog and/or in this topic. Don’t forget to include a nice photo and some details about the used beamer (brand, type, native resolution, etc).

Note: you will need to turn on vsync in your display controlpanel.

*update*
The new version runs on Mac OS X aswell smile thanks to Pawel ’solydzajs’ Solyga!

Tools:
Beamer Latency Measurement Tool v0.2 - windows binaries
Beamer Latency Measurement Tool v0.2 Sourcecode - sourcecode

Source:
Multigesture.net

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My multitouch blog: http://www.multigesture.net
Howto: Compile touchlib on windows XP/Vista
Howto: Compile touchlib on Ubuntu Linux
Downloads: Touchlib SVN builds

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Posted: 04 November 2007 09:02 AM   [ Ignore ]   [ # 1 ]
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one of the better topics on nuigroup, gonna post our results hopefully soon here, and i invite everybody to share there specs with the rest as well

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http://www.multitouch.nl / natural-ui.com

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Posted: 06 November 2007 02:58 PM   [ Ignore ]   [ # 2 ]
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Hi,

I know that the new Panasonic PT-AX200U has a special gaming mode:

“With respect to Gaming Mode, Panasonic has accelerated the video processing such that the video delay from the buffer is only 0.3 ms, compared to 0.9 ms in Cinema and other non-gaming modes.”

http://www.projectorcentral.com/panasonic_ax200u_home_theater_projector.htm

Best regards

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Posted: 10 November 2007 01:55 AM   [ Ignore ]   [ # 3 ]
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My cohorts and I have tested the Panasonic and there is still significant lag.  More annoyingly, we are having issues with getting our install of linux to run it at the full 60hz refresh rate; some utilities think the card and projector are at 60hz, while others seem to indicate 50hz.

Note that although Panasonic reduced the particular video buffer processing time from 0.9ms to 0.3ms, the average projector latency is somewhere in the neighborhood of 30-40ms, so it’s not that great of an improvement.  The lens pan feature is very handy for alignment and calibration, though.

On a related note, a friend of mine has indicated that some folks are having issues playing games like Guitar Hero on large HDTV screens because the latency introduced by all the video processing throws the video out of sync with the audio.  Has anyone else heard of something like this?

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