CurtPalme.com Home Theater Forum

[stridsvognen]

I had a fun experience the oher night after a bit of arguing about scaling, and source direct in another thread.

So what i did was to setup my Radiance and output 576P 100hz.

Spend some time playing with the stigmator to make the dots bigger to fill the scan line gap, also played with the focus.

The first impression was quite wow.

I have never made it before thinking that the scanlines would be to anoying, but with a decent distance to the screen i dont see them, about 3m from a 2m wide screen.

I later changed the framerate to 150hz, running a 81Mhz pixel clock. Kapow..

The detail level, and the dynamic range in the image is just amasing.

But i like to know how to make this better, whats the best way to adjust the dot size.? make them even in light output, not peaking in the center.

And would it be possible to do the same with NTSC 480P DVD signal.? Or will that be pushing the dot size to much.?

In the future im planing to run 2 Marquee 9500LC Ultra machines, so i can tweak one to SD source, and the other to HD.

If its better to adjust the mecanical magnet setup for SD. ??

[barclay66]

Hi,

I think that a combination of Astig and Focus settings will do the trick. I wouldn't touch the magnetic rings though.
Instead You could try the following procedure:

- Lower the focus on all three colors by 10-30% (not quite sure, raising could be needed instead)
- Set the electrical Stigmator settings such that the "smearing" happens vertically only

Now You can control the scan line size (line height) through the focus setting.

Regards,
barclay66

[stridsvognen]

Thanks barclay.

Its more or less what i did, and if ill be able to adjust the stigmator so the dots get vertical longer, ill never go back to scaling.

Its clear to see how scaling do mute some details.

There is 1 downside to it, and it looks like compression artifacts from the source, they also seems to get muted a bit when scaling, and thats the only positive thing i can say about the scaling.

Its a bit funny like i spend some years playing with different scalers to get a better SD image, and for the first time try to display it with no scaling, just gets blown away..

The only thing i do to the signal is deinterlacing and tripple the framerate to 150hz

Normaly i scale to 1080P 75hz, not the smoothest framerate for a 50hz source, but better than 60hz.

Im working with LD scaling to, and there it seems like the massive scaling from 480I 4:3 to a 1080P is a positive and effective noise reduction.

[gjaky]

I am wondering why would degrade the picture quality if you scale the DVD to double size (1440x960), that's a cheap old trick, no interpolation or estimation involved there, just doubling every pixel...

[stridsvognen]

[km987654]

I have found the magnetic setup as specified by the projector manufacturer a compromise. You can make the image sharper for any resolution but of course it's only good for that resolution.

[stridsvognen]

[CasetheCorvetteman]

[CasetheCorvetteman]

Stridsvognen, i ran my DVDs at 576p for years, and also agree it looked nicer than a 1080i upscale. ( watching blurays at 576p was clearly not as good as at 1080i )

Have you tried DVD using a PC instead of a stand alone player? I do put DVDs through the PC in my loungeroom setup now because the Barco wont fill the screen with the 1080p 50Hz signal my Panasonic bluray player pushes out.

I havent tried scaled vs untouched with the PC, i generally leave it set to 1920x1080 all the time.

[stridsvognen]

[CasetheCorvetteman]

I don't use 50Hz for 1080i, but don't have an issue with it for 576p, I don't get any flicker at all.