144hz DLP Link - explain? - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 10 Old 12-29-2016, 07:09 AM - Thread Starter
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144hz DLP Link - explain?

I just recently got a DLP projector and some DLP Link glasses that are "144hz".
I mentioned this to a friend who is also into audio/visual stuff and he was trying to understand how they could be 144hz.
I wasn't able to explain it - I was hoping someone could clarify it for me. I tried google but just got reviews and ads for 3D glasses.
I do understand how DLP link works, it is just trying to understand what 144hz is referring to.

I understand that 144 divides evenly by 24fps - but beyond that I can't explain it.

As a side note everything I play comes across the projector as being a 60hz source, so that may be adding to the confusion.

-Aaron
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Last edited by PTAaron; 12-29-2016 at 10:22 AM.
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post #2 of 10 Old 12-29-2016, 07:25 AM - Thread Starter
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I think the confusion is coming from his understanding of displays using multiples of 60 for video vs film/movies using multiples of 24 - I lack the technical ability terminology to adequately explain the discrepancy.

-Aaron
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post #3 of 10 Old 12-29-2016, 11:33 PM
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Those glasses were probably designed for PC use, where 144hz is a standard for frame-sequential 3D. Frame sequential is where you display the left eye, then the right eye as regular frames (this is instead of passing both the left and right eye video in a single frame like frame-packing, top-and-bottom or side by side).

All PC capable 3d displays have to support 144hz (giving 72hz per eye).
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post #4 of 10 Old 12-30-2016, 11:18 AM - Thread Starter
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Quote:
Originally Posted by Worf View Post
Those glasses were probably designed for PC use, where 144hz is a standard for frame-sequential 3D. Frame sequential is where you display the left eye, then the right eye as regular frames (this is instead of passing both the left and right eye video in a single frame like frame-packing, top-and-bottom or side by side).

All PC capable 3d displays have to support 144hz (giving 72hz per eye).
Thanks!

-Aaron
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post #5 of 10 Old 01-01-2017, 06:13 AM
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The 144hz comes from tripple flash. 24hz flashes 1 frame 3 times to each eye. 60hz source will flash 1 per eye and glasses will run at 120hz. This is why the old 120hz glasses work fine with 60hz source but fail with 24hz source.
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post #6 of 10 Old 01-01-2017, 06:21 AM - Thread Starter
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Quote:
Originally Posted by rekbones View Post
The 144hz comes from tripple flash. 24hz flashes 1 frame 3 times to each eye. 60hz source will flash 1 per eye and glasses will run at 120hz. This is why the old 120hz glasses work fine with 60hz source but fail with 24hz source.


That makes sense. Thank you!

-Aaron
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post #7 of 10 Old 01-02-2017, 10:17 AM
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Quote:
Originally Posted by Worf View Post
Those glasses were probably designed for PC use, where 144hz is a standard for frame-sequential 3D. Frame sequential is where you display the left eye, then the right eye as regular frames (this is instead of passing both the left and right eye video in a single frame like frame-packing, top-and-bottom or side by side).

All PC capable 3d displays have to support 144hz (giving 72hz per eye).
120hz is the standard for frame-sequential 3D. As far as i know none of the 144hz PC displays work at 144hz when in frame-sequential 3d mode. They use 120hz for that.
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post #8 of 10 Old 06-01-2017, 10:43 AM
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Just to clarify (sorry so late)...

DLP link flashes the left eye, then a red frame, then the right eye, then a red frame. This is repeated three times for each frame of video.

You've already done the math on this and get that. 3 frame flashes at 24 frames per second is 72Hz, then two eyes, and you have 144Hz.

The red flash used on DLP Link projectors is what keeps the glasses in sync with the 3D. The glasses purchased vary wildly on their quality with allowing red light through them. Better ones will sync perfectly and you will have a much better viewing experience. Weak ones will have an image with a bit of 'red' to them. This is common on cheaper glasses.

Honestly, I have no idea with computer monitor, but I am more knowledgeable with DLP Link projectors. I don't believe computer monitors work at all the same as DLP Link does with the 'red flash' between left/right images.
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post #9 of 10 Old 06-20-2017, 11:48 AM
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If the dlp link red flash is the same after the left and right picture, from where my gonbes g05 glasses know the correct order?
It doesnt have a swap button, and left right order is ALWAYS good. How?
Left eye flash should be a little different than right eye flash. Or?
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post #10 of 10 Old 06-21-2017, 02:09 PM
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It's not always red with other projectors, by the way. Mine looks more white.
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