I have a friend whos 18" Viewsonic n1800tv's backlight just went out-perfect for the diy projector fanatic! I was wondering if anyone has ever dealt with this model and also if I could get away with using the standard triplet or if I would have to use the pro lens? All comments appreciated-thanks.

I believe you would have to use the pro lens. I am not sure if the standard triplet can fit such a large picture. I am positive that you could not use the standard fresnels, they are not large enough for that panel.

Even if you could get fresnels large enough to accomidate this panel (3Dlens.com may sell them), and could use the standard lens, you would need the projector in front of the seating. Otherwise the image would be extremely large - and likely too large for your liking.

As far as the panel, yes, that is wonderful for DIY! I have never heard of anyone using this panel before, but by all means give it a go. It would be difficult to use it without a backlight

Good luck,
Nick

Yes you are probably limited to using the PRO, not cheapest, but you get what you pay for.

Indeed. The pro lens is excellent quality. I don't have a single complaint, the focus is perfect. And when coupled with a 17" monitor (I assume it is similar with an 18") I don't really perceive a screen door effect. This has nothing to do with the lenses, but it is an advantage of going with a larger panel. I think it has to do with the pixel pitch, or distance from the center of one pixel to the center of the adjacent pixel. A smaller pixel pitch means smaller pixels, which cuts the screen door dramatically.

So if I need the pro lens are there any other options aside from the lumenlab pro lens? I love lumenlab and all but 200 is a bit much for me to shell out on just the lens- does it just need to have a fixed focl length of 500mm? Why wouldnt something like this work http://www.nextag.com/Canon-58mm-500-Close...ARE-PRICES-html ?

some people have been using lenses from opaque projectors that appear to have good results... I wouldn't guess as to whether they have the field angle required to use an 18" LCD.

you may think that $200 is alot for a triplet, but it is actually [/b][/i]very[i][b] inexpensive. Triplets of this size can easily run into the $1000's of dollars. Nice thing too is that you know it will work as it's been designed to work with LCD's up to a 19" widescreen.

The 500mm focal length was a design decision... probably offering the best possiblities on throw for 15" or 17" LCD's. The lense you've linked to is a simple singlette lens designed to work in front of a camera lens... this is not even close to what you would need for a projection application. At the very least you would need a doublet, but even then you would have questionable quality... the triplet is a standard for projection use.

cheers,
gs