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Topic: Projector Latency
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Joined: Apr 20, 2006
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We are looking at 8 to 10k lumen projectors for our venue. Other than the brightness latency is also very important as we will be displaying a live speaker. Other than Barco, no other projector manufacturer seems to have latency values handy. They all have to call the "engineers in Japan" or something like that. Though Barco far exceeds the minimum specs we need, $65 grand on a single 10K projector is out of our budget...especially since we need 2.

We currently own a Sanyo and as far as I can tell, it is adding over 100 milliseconds in latency. Thats over 3 video frames of delay. This is completely unacceptable. Barco has a very respectable 16 ms but again it has a price limitation for us. We are considering Sanyo's XF45 but as of yet still haven't gotten any latency values back from them.

I am open to suggestions of other brands that would meet our 2 main qualifications.
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Joined: Mar 28, 2005
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You should expect at least 3 frames of latency on any projector for upconversion and deinterlacing to be done accurately. I am not sure if it is possible to avoid this by using an external upconverter, but would expect that to perform the same way.

A high quality projector would really require several frames fed into a frame buffer to be processed, properly deinterlaced, interpolated for motion, then fed to the screen. A 16ms latency - from of ALL companies - Barco - sounds like a lie - from a company that is happy to do so. Barco has pretty much ruined any trust that I might of had with them in their actual execution of a product.

Sanyo is one of the best players out there for the money, and if they aren't good enough running 1/20th of a second behind the speaker, then your choices are very limited when you are on a budget.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
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What we tried to do to fix our latency was exactly as you suggested. We used an external scaler that was supposed to be faster than the one installed in the projector. We then fed the projector the signal in its native resolution so that it could bypass much of its processing. It did not work. The latency was exactly the same.

Are you saying you think the Barco specs are untrue? What was your experience?

We would like to feed the projector as close to its native resolution as possible so that its internal scaler will not have to work so hard and thus be faster. Is this a wrong assumption. Am I ignorant of all the internal workings?

The problem is that our projectors are about 80' from the source and vga cable will not send that far reliably. We must send an analog video signal in order to get it that far with quality.
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Well... VGA is an analog signal and can be run hundreds of feet and with the proper setup can be run up to 1,000 feet at 1600x1200 resolution. Still analog.

The issue you will have is that if you are shooting in something other than the native format to the projector, then any decent processor, whether it be external, or internal to the projector, will need several frames put into a frame buffer to properly deinterlace the source material for final output resolution.

My experience with specific Barco models is limited. My experience with Barco as a company indicates that they very rarely know what they are talking about, don't properly engineer their products, and have ZERO customer support - so once you buy the product, if you aren't happy, you are SOL. While, they may deliver for you on that one aspect, I can almost guarantee that the projector will undergo a far more serious failure at some point that will be much worse than the latency issue. It is in their nature.

Not many requests for super-brite projectors though. So, you have very limited choices and far more limited when you budget isn't open.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.