I have been looking at XGA as a real requirement for a DIY or commercial projector, but am not sure their is real validity to this. The greatest applications for a pj are dvd's, gaming, and tv watching, with dvd's and gaming probably being the greastest by far. Unless you have an HTPC that can scale dvd's up, you can only get 480p out of them, which is well short of 1024 * 768. The same goes for console gaming, unless you have an xbox, and even then you can get higher res with only a few games and expensive cables. Tv of course can be fairly easily ramped up with a tv box, but is that enough to warrant the higher res. I have seen commercial pj's with compressed HD signals that play a cable feed with a beautiful picture, and cost under $1000.

We keep making our DIY pj's more and more expensive, with most being over $600, when commercial 800 *600 pj's are around $850 with contrast ratios around 2000:1, which greatly enhances picture quality in a way we can not.

I am not sure that I am correct about this topic, but it makes me wonder if a smaller lilliput with 800*600 might not suffice well enough in a much smaller package, or if the space gains of a commercial pj with up to 4000 hours of lamp life might not be worth it.

I really like the hobby aspect and lamp life of DIY projectors, but the size of DIY coupled with increased costs due to new materials, and decreased commercial pj's with improving lamp times makes for a tougher decision.

Well, I really meant for this to be a discussion about uses for resolutions, but began rambling. Sorry about that. Also, if I am incorrect about the advantages for xga res with the above applications, please speak up, as I am looking for more justification to go DIY instead of commercial. Just seems like a lot of fun!

Its not so much that the resolution is higher but that the pixels are smaller so you get less of the "screendoor effect". The screendoor is the black lines in between the pixles so for a given projection size if the pixels to space ratio is roughly the same but there are more pixles you get more image on the screen.

800x600 = 480K
1024x768 = 768K

So the image looks better, and the magnification is less so less distortion. Most of those going for 17"+ LCDs are going for HDTV support. It seems that most europeans are happy with 7" (800x480) and americans want 15" and by nature some amercians need to have a bigger bader pj than next door, bigger = better its the american way!!!

I can see your point in regards to "budget setups" and cost run-up but lets clear a few things up first

For those using an htpc or N6 a 15" xga LCD opens up more IQ enhancement options. And as pagercam states, extra pixels can only help, not hurt IQ.
A 15" xga lcd makes PC gaming possible since newer PC games look horrible at anything under 1024x768 imho.

The compatible lilliputs state xga support but can only display an actual 800x480, their ads are borderline false-advertising imho. The compatible ones aren't cheap either

As for commercial PJ's, there's plenty of hidden costs with them. The units are expensive to service and that fact alone has almost rendered them as "throw away" items (the low end ones anyway). The bulbs max anywhere between 2-4000hrs and cost $275-$500 average. The cost of buying, maintaining & servicing one for X years can easily cost many thousands. The choice was easy for me when i realized this: i can build an ultra-high end DIY with an SGI 1600 that'll last 20,000 hrs for the same price as a low-end commercial unit.

I guess it all depends on what you'll be using it for. I wanted more htpc and PC gaming options so i went with a 15" xga setup. Having it at diy prices was the icing on the cake

The Lilliput screens are very nice, as they can make for a compact projector, but you have to take into account how big your projected image will be. The smaller the LCD, the faster screendoor will show up.

Ignoring the screendoor on the commercial projectors, the bulb cost is the major factor. As soon as you have to replace a couple, the 'saving' you made over the DIY projector goes out the door.

Nope, I think it's mostly Europeans who got into DIY projectors before coming to Lumenlab that use the smaller screens. Everyone else on here wants 15" minimum. Well, the UKers at least.

If I could justify the cost, I'd be going for a 17" LCD and pro lens. Maybe next time....

I have just finished ordering most of my supplys and only add up to 372.51 not including material for the box. You just need to find deals. An example:

Viewsonic VG150 dark screen ebay 125.50
TVBox ebay 62.00
Fan ebay 6.94
400W Ballast Bulb and Base from lightingcloseout.com 77.50
25' VGA cable ebay 12.90
VGA splitter ebay 5.60
LL Lens kit and UV screen 82.02

I shouldn't have more than $50 to spend for wood, wires, switches, and tempered glass.

personally, my whole reasoning behind the projector is PC gaming, and I know what XGA looks like blown up on the wall from work projectors, and to me its ugly (for gaming), so the only way i was going to do this was if it was capable of SXGA (1280x1024) which is where games start to look very nice, even when blown up on the wall.

i thinkt he screen door effect alone however would get annoying at anything less then XGA anyway, even in movies.

The resolution is not the thing that effects when screen door is noticed. The physical size of the panel is what counts. Even if you had a commercial projector with 1600 x 1200 pixels, the screen door would be more noticeable than a 15" panel running 800 x 600.

Heck, anyone can spend $1000 if they so choose to... Just because a lot of people are showing they are spending $600 on their projectors, doesn't mean that is how much it cost to build one.

Someone who was REALLY wanting to build one for the lowest budget possible could easily do it for $300. It would just take a lot more discipline on their part.

Most of those who spend $600 are simply "Impatient" buyers. They HAVE TO HAVE IT NOW! So they end up spending the $$$ of the first thing they come across instead of "looking for the deals".

I see LCD's go for next to "nothing" on eBay all the time that have simple things wrong with them making them perfect candidates for the LL Project.

Material? Most people would go to Lowes or HD and pick up about 40-50 worth of wood. An alternative is to go find a housing sub-division that is under development... find a house that is being framed. Ask the guys if you could pick up a few pieces of "scrap" plywood...etc. They will certainly tell you "GO AHEAD DUDE! Less for us to have to get rid of!"
And you will SURELY find MORE than the wood required to build a projector.

There are many ways to save on cost. You just have to be "creative".

That's what I did. The 4X8 sheet (pictured in the PLOG) is still at my house uncut.
Since then I have seen tons of materials for building for near nothing...everything from tossed computers for fans, connectors, metal to discard/non-stock/returns bins at local merchants for switches, PVC, hinges, whatever.



patience and perserverance makes a huge impact on the wallet. My blackout cloth cost less than $3 a yard new. Again, I waited till I saw a coupon.



This is no joke. Our old church has a projector that is rarely used because 'it might break' and the per hour cost is too high. The picture has too much screen door and it is dark even with all the lights off, even though it is a middle range unit.

My unit was just shy of $300. Although it is only 800X600 using a QA-1800, our local PUD just 'dumped' 6 truckloads of 15" monitors and I may get access to them at $50.

The factors for going DIY for me was initial cost of picture quality, I can upgrade for pennies and I'm not afraid to drag the thing all over town 'showing off'

Hope this helps

Sure you can decrease costs a little by being patient, but I don't think that is why the cost has risen to $600. It is the increased cost of newer and better bulbs, the use of an N6 instead of a base tv box, upgrades to e-ballasts. Some of these things appear to make a significant difference in allowing us to build a very useable projector for all applications.

Why does a commercial projector have less adjustable IQ than a DIY. You can hook up an HTPC to a commercial projector.

Of course even with diy costs increasing and commercial pj's decreasing, DIY is still cheaper. My main difficulty with it is the increased size of the pj over commercial, and I just wonder if the advantage of increased res is enough to justify the increased size. I guess that just depends on each person.

Regarding increased costs of commercial pj up keep. Most that I see have at least a 3 yr warranty. Just a side note.

Please, ignore the rez for now. Concentrate on how big you want the projected image to be. Then, if the image is large enough for screen door to become noticeable, decide if you can live with that that amount of screen door every time you watch something on your projector. That way, you can decide whether you need a 15" panel, or if a Lilliput would do the job (or even a commercial projector).

That is true, but the only real upkeep of a commercial projector is the bulb, and they are not covered by the warrenty.

I could be wrong but I always thought the screendoor was effected by the DOT PITCH specification (the space between the pixels) which has nothing to do with how many pixels or pixel size, I think most LCD's are .25-.30 no matter what size they are (except maybe polysilicone LCD's) so resolution and size I didnt think effected screen door, well size of panel can indirectly by not magnifing the DOT PITCH by as much to get the same size projection

Screen door isn't affected by the number of pixels, but it is affected by the LCD size (and therefore the size of the individual pixels). As the LCD increases in size, so the the size of the pixels increase (but not the gaps in between the pixels). The ratio of space taken up by active pixel increases as the LCD increases, which means you can magnify the image more before the gaps in between the pixels becomes too noticable (screen door).

Basically what you said Greg, except that the size of the LCD does have a direct bearing on when screen door starts to become noticeable.

An easier way to picture things perhaps...

Another thing to consider is that larger LCD's have a larger aperature so more light passes through. Although there is still the etendue of the projection lens.

I have to agree with sjetski71. The maintenance costs are what intrigued me most. I have 4 commercial projectors sitting around that I won't even consider replacing lamps on unless I decide to retrofit an Icecap ballast and HQI double ended lamp.

As far as resolution. The more the merrier. I'm sure I can find plenty of uses for those pixels with all the console emulators, design software, and miscellaneous applications that make computers great. To each his own. Everyone must make the deciding factor of resolution for their needs in the end. Which is why my first DIY project was the PSONE LCD in the living room. Now to work on my 15" XGA for my workshop. Wish me luck!