Digital projectors and strobing

[Nocta]

Hi guys,
I've been reading you for quite a while now and first I want to say thank you for sharing this really interesting knowledge you have about motion-blur and other "monitor topics".

I came here first for emulation and modern gaming purposes (and kept my CRTs so far) but I now have some questions about movies...

I'm thinking about getting a projector to handle all my movies / TV shows and I would love to know more about the motion-blur effect (and other important points to know if there is) you get with digital projectors.
I read quite some topics about projectors on the web and it seems that some videophiles still prefer "Large three-lens CRT" ones (called Tri-tubes) and I started to wonder if it's because of this motion thing...

There is different problems though with this case:
1- this kind of CRT projectors is really difficult to set-up (it has to be done by a pro during a full day apparently!) and you should better be sure that you will never move out before installing them!
2- they can handle full-hd sources but in no way 24p so you still have to deal with NTSC or PAL "modifications"...

So here it seems that no solution is really perfect.

What I'm wondering then is :
Is it possible to have some kind of "film-style motion" (maybe through 24p shutter at 48 or 72hz?) that kind of recreate the original film experience we used to have with the 180 degree shutter on film projectors?
Also how do they handle this nowadays with digital projectors in the cinemas? It seems that they use the DLP technology, so I guess it is the way to go but I don't know more.

If anyone has more knowledge (not difficult ) and can help me to understand better and take the right decision to enjoy movies and tv shows in the best conditions, I'd be really happy!

Thanks in advance.
Nocta

[Chad]

CRT ones are terrible for refresh rates.

Best bet is a 3-chip DLP. The input electronics vary, but the DLP chips themselves can run at thousands of frames per second.

I'm not sure who sells what model, but I know Christie sells Mirage projectors that can do 2K/2.5K/4K at 120fps.

The nice thing is that DLP refreshes very cleanly. No LCD fade times or uneven CRT refreshes. So you don't have much of any motion blur effect.

[Nocta]

Thanks for your answer Chad.

What about 1-chip DLP? They are much cheaper and so I could most likely afford one of them so i'm interested!

[Chad]

Unfortunately, 1-chip DLP's must send out red, green, and blue in sequence, so fast moving objects on screen (or worse, moving your eyes across the image) will result in a rainbow effect. It's worse at high framerates.

Christie sells a 120Hz single chip projector that doesn't have a bad rainbow effect, the WQ-L. It's not cheap though, so it defeats the purpose. I'm not sure what the best price on a 3-chip HD projector is.

There are also LCOS projectors that can do high framerates, but I don't know the quality and price tradeoff compared to DLP.

Nearly 100% of cinemas use DLP or SXRD (which is Sony's brand of LCOS). The DLP's are better over the long haul because the SXRD panels lose contrast over time. Interesting fact, nearly all of the projectors are able to run at 144Hz, which allows them to show 3D movies at 24Hz per eye by flashing Left-Right-Left-Right-Left-Right all in 1/24th of a second. This helps make the 3D viewing more comfortable, though experimental films like UFOTOG are showing that you can show stereo at 120fps and not have to repeat any of the images so you get a much smoother framerate. The projectors that UFOTOG runs on, however, cost at least $30K.

- Chad

[Nocta]

Thanks for the clarification Chad,
I'm going to search for a 1-chip DLP without too much rainbow effect then so I can stay in my budget (<1000€).

Edit: It seems after further research that the BenQ W1070 is pretty good and the price is just crazily low (around 700€)!

[Chief Blur Buster]

Also, enabling the 3D mode adds a black frame insertion, so you can have reduced-persistence 120Hz. There is still motion blur on a 120Hz DLP that makes them fail to pass the TestUFO Panning Map Readability Test. This is due to the sample-and-hold effect as explained at www.testufo.com/eyetracking

So, enable 3D mode on your 120Hz DLP, even if you're using it for only 2D. The black frame insertion is used as a shutter-switch interval, but has the beneficial effect of reducing 2D motion blur for computer use and gaming. This is also explained in a "Lightboost projectors" article at http://www.blurbusters.com/gigantic-120 ... projector/

[Nocta]

Thank you Chief, I'll definitely use it for gaming.
It seems that there is no crosstalk in 3D on this model, so do you think that it means I can play a 60fps game in 3D mode on this projector and get a proper black frame insertion/strobing?

I guess though that for movies and TV Shows, is it better to just use the normal 2D 24p/60p mode, right?