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[EXPERT TIPS][MARK REJHON]

DILA Resolutions via PowerStrip

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(10/1/00) DILA users! Perfect 1360x768 (16:9) and 1360x580 (2.35) on an unmodified DILA!

"Hi!

Thanks to my visit to AVSCIENCE, I had a chance to really play with a DILA projector powered HTPC! Now I know how to setup pixel-perfect 1360x1024 with no jittery pixels. In fact, I managed to make exact timing duplicates into 1360x768 (16:9) and 1360x580 (2.35:1). All of them locked to the exact scanrate and pixel rate, so you don't need to readjust your Tracking/Phasing control.

The picture quality of a DILA is great via HTPC, provided 1360x1024 is the mode that is used. DVD and television (via dTV software, treating a HTPC like a doubler/scaler) works great on the DILA. Doing 1280x720 or 1360x720 from the HTPC for the HDTV input is MUCH easier to do, but yielded terrible vertical scaling artifacts. The below is a much better way to get a 16:9 computer resolution that has NO scaling artifacts at all.

Use input SXGA3, not SXGA1 or SXGA2, for all of these custom resolutions. These modes required Tracking=24 and Phasing=0 on my system. Some test patterns got slightly worse while some got slightly better, but Phasing=0 gave the best results overall, and made computer text pixelly-sharp at close distances with no fuzzy edges. It is highly recommended to calibrate Tracking and Phasing on a fine black-and-white vertical lines or checkerboard pixel pattern. This can be found in DispalyMate, but you can make a makeshift pattern and tile it as background wallpaper - that does the job.

These are PowerStrip 3.0 screenshots. PowerStrip 3.0 is essential for this, as older versions of PowerStrip will not work. You need to be a registered user of PowerStrip - so purchase the older version anyway. This works on GeForce cards, the card being used right now is a GeForce2 MX. Be warned, it is very difficult to create multiple resolutions with exact dot clocks in PowerStrip 3.0 - I am talking to Ashley at Entech Taiwan to address this very issue, since this is the first time I had a chance to do a REAL torture test of PowerStrip 3.0. (I use a multisync CRT projector at home, so I don't have as big a need for PowerStrip 3.0 at home).

With PowerStrip, you can use vertical picture position to top-align or bottom-align the images. Right now, they are centered vertically as a starting point.

Then you can instantly switch between 1360x1024, 1360x768, and 1360x580 and using only the zoom lens of the DILA to make it fill the screen. You don't even need to use the DILA's vertical picture position. You don't even need to re-fiddle with the tracking/phasing controls, because all 3 resolutions are *perfectly exact* in terms of timings (dot clock). There were no defects and no mouse pointer problems on the GeForce2 MX card during testing. I am using Detonator3 drivers from www.nvidia.com .

Be warned, this won't help your inability to vertically reposition HDTV images on an off-the-shelf DILA - that still requires a DILA modification (which I believe can now be done via DILARD software). I haven't tried DILARD, I just played with an unmodified DILA - it's now possible to use a 2.35:1 screen in a constant-height varying-width configuration for DVD and TV, provided all of that is piped through the HTPC. (dTV is a deinterlacer program for analog TV that has 3:2 pulldown detection. It's a TV viewer that replaces the viewer that comes with many TV tuner/capture cards. More info at www.dscaler.com.

Here's the timings for 1360x1024:

Here's the timings for 1360x768:

Here's the timings for 1360x580 for 2.35:1 projector screen setups:

Since the Advanced Timings does not currently let you change the active lines/pixels (confusing, I know), you have to click "Custom Resolutions..." first to add it, THEN return to the Advanced Timings to fill in the rest of the values. It's easy from there, because the DILA continuously realtime synchronizes as you make adjustments.

Warning: PowerStrip 3.0 Build 51 (and probably similiar builds) has some bugs that causes things to screw up if you hit ESC. I lost sync quite a few times when pressing ESC (it's supposed to revert, but it doesn't!). So click Cancel instead of hitting ESC, if you are at least able to see the screen.

Warning: Adjusting with PowerStrip 3.0 can be a more frustrating-than-expected experience even for power users who understands timings very well.