All this motion blur excitement ...

R

rdqlus

Limp Gawd
Joined
Mar 24, 2010
Messages
368
Wondering why people concerned about motion blur don't just use 120Hz DLP projectors?

There are a few downsides:
- lower resolution (800p)
- possible rainbow artifacts
- complicated screen setup and space requirements

But those are offset by the fact that it's freakin awesome with no blur or lag (and no 3D crosstalk if you're into that sort of thing). Also, HDMI 2.0 will likely bring with it a new generation of 120Hz 1080p projectors. As for rainbows, I've only seen them myself with ridiculous fast eye movement (I was purposefully trying to see them in this case) or when running a special video test with a fast moving high contrast feature (ie: white line moving over black background). I've never noticed a rainbow in a game ever ... maybe I'm lucky.

Anyone else with any thoughts on this? I tried out some of the tests at www.testufo.com last night. Projectors looked pretty sweet :)
 
Last edited:
Yes, there are some rather nice 120Hz DLP projectors available.
The Optoma GT720 is capable of doing 120Hz from a PC, and has far less motion blur than most projectors.
This allows big screen gaming (wall sized images, over 100 inches), at 120Hz refresh rate, 3D glasses compatible...

Optoma_GT720-300x180.png


One thing I am curious is whether any of the projectors have a black frame insertion mode.
On your DLP, can you read the street names during the new TestUFO Panning Map Test during 960 pixels per second motion?
Only a few displays such as CRT and LightBoost pass this test. Try adjusting your projector's black frame insertion modes and 3D modes, until the motion clarity is maximized, and see how it looks! Almost all DLP's fail this specific test at 960 pixels/second.
 
Last edited:
Yeah I can make out the street names; Front Street, Queen's Quay, etc. I couldn't read Bathurst Street but with the black line that's drawn through it I could barely read it while paused.

I couldn't find any Black Frame insertion options when I looked through the menu just now. I have my projector's display mode set to 3D. I needed to do this to eliminate ghosting when I tried out The Witcher 2 in 3D Surround and I've just left it there ever since.

I just hope that Optoma makes a Optoma GT1080 model that mimics everything about the GT720 but bumps the resolution up to 1080p. Right now my only upgrade is to Christie Digital units at outrageous (never gonna happen) prices.
 
rdqlus said:
I have my projector's display mode set to 3D.
Click to expand...
Quite interesting! If you can read the map text, you've already got LightBoost-like strobing!
Enabling 3D mode is known to automatically enable black frame insertion, since that reduces 3D crosstalk while the shutter glasses are opening/closing shutters.
That would obviously improve motion resolution, even just for 2D use.. For a 50:50 black frame at 120Hz, that gives you 1/240sec frame samples (motion blur of 4 millseconds).

So, essentially, if you are able to read the small text in the TestUFO Moving Map during 120Hz, this confirms you are using a DLP projector that has strobing or interpolation. Since you're not using interpolation, that means you've got strobing.
This is because non-strobed sample-and-hold 120Hz always has a scientifically guaranteed minimum of 8 pixels of motion blur at 960 pixels per second, making it impossible to read small text.

Topic needs to be renamed "120Hz DLP projector with black frame insertion: LightBoost-like big screen gaming"
 
Last edited:
Mark Rejhon said:
Quite interesting! If you can read the map text, you've already got LightBoost-like strobing!
Enabling 3D mode is known to automatically enable black frame insertion, since that reduces 3D crosstalk while the shutter glasses are opening/closing shutters.
That would obviously improve motion resolution, even just for 2D use.. For a 50:50 black frame at 120Hz, that gives you 1/240sec frame samples (motion blur of 4 millseconds).

So, essentially, if you are able to read the small text in the TestUFO Moving Map during 120Hz, this confirms you are using a DLP projector that has strobing or interpolation. Since you're not using interpolation, that means you've got strobing.
This is because non-strobed sample-and-hold 120Hz always has a scientifically guaranteed minimum of 8 pixels of motion blur at 960 pixels per second, making it impossible to read small text.

Topic needs to be renamed "120Hz DLP projector with black frame insertion: LightBoost-like big screen gaming"
Click to expand...

That explains the brightness drop when I enabled 3D mode. It isn't an issue for me since the screens are only 36" each and the projector is placed less than 2 feet away from them. I actually had to paint the screens a dark neutral grey and leave the lamp in Eco mode so as not to be blinded.
 
You must log in or register to reply here.
Back
Top