Ok, so here is the deal. I'm going to be moving around a lot the next few years and I want a nice TV that is somewhat compact and portable, so naturally a projector seems like a good choice. I am thinking of using this LCD TV to make a DIY projector, hopefully it will work. http://www.bestbuy.com/site/olspage.jsp?sk...d=1218054462302

It is the smallest, cheapest 720p display I can find with all the desired inputs (how many projectors have HDMI and coax?) I want to use 15" rather than 17 or 19 because i want the projector box to be as small and streamlined as possible for transportation purposes. 1080 would be nice, but I usually can't tell that much of a difference and due to price and space limitations I certainly am not going to be picky on that aspect of the screen.

My biggest dilemma is price. I want to use that 15" widescreen LCD, which would require the Pro Fresnel set. However, there is NO WAY I can justify $200 on the pro triplet. I've seen conflicting posts on this site about whether or not the S15 triplet can be used with the pro Fresnel set or not. If it truly cannot work, what type of lens should i look for (focal length, cheap) The rooms that this projector would be used in are not huge, so I'm not worried about needing a long throw. I plugged the numbers in on focalcalc and it showed the 650mm fresnel and 320mm triplet producing a 100" diagonal at 8', which would be fine if the combination actually works. I suppose this question isn't urgent, I plan to build the projector over this summer if lumenlab ever has the parts in stock, most have shown as back ordered for some time now.

Also, how much wiggle room would I have on this type of setup? how close would the projector to screen distance be to have a crappy picture? How far away? The projector won't always be in the same room setup so the same distance may not always be possible. At different times this projector may be used for my laptop, Wii, television viewing, or bluray player.

I'm fairly comfortable with working with electronics and soldering as I have installed mod chips in game systems before and built a custom Wii nunchuk for a friend. I have access to and experience with woodworking equipment as well as laser CNC machines for acrylic or thin wood. I'm not too worried about the case building aspects, but a little worried about wiring everything up correctly. I plan to purchase all of the wiring/electrical components materials from the lumenlab store, assuming they are in stock.

Also, if that LCD has anti-glare coating, how risky is the stripping process to a first time builder? I wouldn't want to risk killing a $150 screen if I can avoid it, but obviously not having anti-glare is better.

I hope that this post is not redundant, I been contemplating building a projector for nearly a year now and have checked these forum threads frequently for answers, but I am still confused about the whole pro Fresnel issue and what type of lens triplet will work and be cheap. Thanks in advance to any help you guys can provide.

Welcome to the world of posting!

That's a pretty decent price for a 15.4" LCD TV. Kudos for doing the research on S15 lenses vs. Pro.

You can't use the 650mm Pro fresnel with a 320mm triplet, though. If you're still shooting for a short throw with the S15 lenses (320mm triplet, 220mm rear fresnel and 317mm front fresnel - or similar), you're looking at about a 7.4 foot throw for a 100" 16:9 screen. If you go for a 120" screen, you'll have a throw of about 8.7 feet. You might experience dark or blurry corners with the S15 lenses, as you've probably read.

You can move the projector as close, or as far away from the screen as you want (the brightness of your projected image will diminish as the distance grows) - as long as you can adjust the distance between the triplet and LCD. You can experiment with different throw distances in FocalCalc - you'll notice that the LCD Distance will change as you change the throw. Your enclosure, using S15 type lenses, could be around 24" - 26" long.

If you want to go with a Pro type build, you could probably save some money by looking for a Beseler 18" or 22" triplet - then you'd use the Pro fresnels. Your enclosure will end up being about 3 feet long.

It's recommended that you not even worry about the LCDs antiglare until you have the projector working. If you're not satisfied with it then, it's recommended that you try polishing it first, before trying a strip. There is sometimes a reflective layer (also seen here) on the back (backlight side) of a lot of LCD panels that may have to be removed to allow more light through. If your LCD has the layer(s), it would be a good idea to remove it.