LG-Phillips 1920x1200p Projector, My DIYpj completed months ago Options

[c feole]

Yes ,but wouldn't it be brighter if the ag was gone all together.

[jonjandran]

Yes ,but wouldn't it be brighter if the ag was gone all together.

Theoretically it should be anywhere from 5%-10% brighter, but that is heavily debated here.

[SIMUL8R]

Yes ,but wouldn't it be brighter if the ag was gone all together.

Exposed polar has a high tendency to 'grain'. The structure of polar are strands oriented one way (Linearly) which are then sandwiched between two films. One film is clear the other processed antiglared or just clear as I mentioned earlier of gloss polar films. These films protect the polar strands from loosing its film like structure otherwise 'graining' occurs like aged wood after time especially to heat and cold. This graining appears like diagonal lines on projection which is actually your lamp punching through the LCD and then through the cracks of the grain. Here is pic of what I mean, you may have to expand it to see it better.

 Ratatoulle.JPG ( 112.46K ) Number of downloads: 19


Polishing antiglare does offer some brightness and is very safe compared to removing ag alltogether and the risks to graining but it does take alot of effort and several applications. Link to pics.

EDIT: There was a comparison pic of projection before and after polishing by a member that did show the percentage of brightness but I couldn't find it

[Vinch]

@simul8r

nice screen shot there! corners are still bright. may i know what type of projection lens you are using?

mine have brownish colors at the corners and im using a 345mm projection lens, do you think upgrading to a bigger lens will solve the issue?

[Sinner7]

@simul8r

nice screen shot there! corners are still bright. may i know what type of projection lens you are using?

mine have brownish colors at the corners and im using a 345mm projection lens, do you think upgrading to a bigger lens will solve the issue?

Your rear fresnel is probably too far from your lamp arch, try moving your lamp a little closer. If the lamp is too far, you'll have orange/brown corners. If the lamp is too close you'll have blue/gray corners. The "sweet spot" is in between these extremes. You'll still have some dimness at the corners but only slightly discolored if you have the "sweet spot" aquired.

[SIMUL8R]

@simul8r

nice screen shot there! corners are still bright. may i know what type of projection lens you are using?

mine have brownish colors at the corners and im using a 345mm projection lens, do you think upgrading to a bigger lens will solve the issue?

10.6" WXGA Samsung with a 457mm (18" Beseller), 575w HMI lamp combined with a double precondenser set up. Check my 4th build. And as Sinner mentioned, you might be to far from your rear fresnel. With a precon lens you should be even closer than 220mm unless the diameter of the lens is to small to cover your 15.4" WUXGA.

[c feole]

I removed what was thought to be the ag under the two reflective layers. It was the polar and alot of glue. I replaced it with high contrast polar that I had on hand from polarization.com. There in Texas and really easy to work with. I have to say the picture is brighter however a little green looking because the under side of my lid hasn't been painted flat black yet.

[Vinch]

@sinner, simul8r

thanks for the tip

@c feole

is it easy to replace the polar film?