So, i've been debating building my own project for about a year now. I have, what I believe to be, a great setup in my basement that is screaming for a projector.

I've spent many hours in this forum reviewing plogs and all the basics...so I'm fairly up-to-speed.

However, I'm at a point where I don't want to begin until I get a better estimate for what it will cost($$$) in the end. I'd love to keep it $500-$700 USD completed. Of course, WUXGA is ideal, but may not be possible considering costs. I thought I would start my first post to see what the experts recommend.

Here is an image of my sketchup basement.


The beam across the top of my ceiling is as far back from the screen as I can go. I will just be creating a simple straight through box design, the size of the box I placed in the image is just a rough estimate for illustration purposes.

So, given the dimensions of my basement, what would you do?

I've read somewhere that 220 triplet is a good place to start, but using FocalCalc, i see that puts me at around 6.7' from the screen. I'm assuming not split because I don't really know which is better in my situation. So I changed to 320 and I'm getting closer, like 9.7' from screen...but that puts my distance between lcd and triplet at 14 inches plus about a foot for the back half(does this sound right?) which is cutting it too close. I think the comfortable area is about 290-300mm triplet. Does that mean that I should consider a varifocal(260/310ish).

Would you aim for higher wattage(400) for this size of a screen? or maybe 150 watts will do for the shorter throw...and it is a basement, so I can make it pitch black.

I haven't had a chance to really price shop each individual items contained in the kits, but generally speaking are they a good deal compared to shopping around for individual pieces? I have my eye on the 15.4 MST at Manhattanlcd and the s15 kit from here. Are they compatible? or do I remember reading the widescreen requires 3dlens pro fresnels?

I have many questions, but i'll stop with that for now.
Any help is much appreciated.
Thanks

Welcome to the forum!

Here's what I would recommend, but don't consider yourself limited to my suggestion.

The S15 fresnels are too small for the 15.4 widescreen LCDs. You'd have to purchase the Pro 220mm fresnel and source the 330mm from elsewhere (3DLens). And your throw would be about 8 - 9 feet, I think. You'll want to go with a split design, because you'll need to adjust for keystoning, as you'll be ceiling mounting the enclosure. If you went with the 15.4 LCD and Pro lenses, your enclosure would be close to three feet long. Stay away from varifocal lenses - they're too small, in my opinion. I would only recommend them for LCDs under 10 inches.

I'd recommend that you pick up one of johnzo's 12.1" 720p LCD Kits with the MST controller - he's only got three left. ($199.00)
You can grab his pre-cut 220mm and 320mm fresnels for the 12.1 panel ($19.00)
And his 320mm triplet ($25)
I'd recommend starting with a 250W double-ended (RX7S base or FC2 base) or single-ended (G12 base) metal halide lamp and ballast (magnetic or electronic) - pricing varies. I'd love to find a single-ended (G12 base) or double-ended 250W ceramic metal halide lamp. The smaller lamps are easier to position and adapt a reflector to.
Speaking of reflector, you can order LL's Pro reflector ($15.00)
There will be other misc. costs - like for wood and wiring and such.

Below, you'll find the results from FocalCalc. It looks like you've got just over 12 feet from the "beam" area to your screen. Figure that your enclosure will be anywhere from 20" - 26" and that should give you a throw of 10 feet and a screen size of 110" in diagonal. If you decide to go with a 15.4 LCD and short throw lenses, you'll get about a 140" diagonal screen at the same throw distance. Get some masking tape and tape off the dimensions of the screen size (both 16:9 and 235:1) on your wall and see if you'll be comfortable with those measurements. Here's a handy Home Theater Calculator Excel spreadsheet for getting your screen width and height measurements.

Good luck to you and we look forward to seeing your results.

Here is an image of my sketchup basement.



Quasi offers good advice. My input is that you would not want your projection all the way to the bottom of the floor, but approximately 18" off of the floor. For a 15.4" panel, the 400W works fine and I recommend LL's lamp because of the high CRI, 6500K color temp and ease of using a reflector. If you use a smaller panel, then the 150W ceramic will work. I recommend Johnzo's light box for the DE bulb. IMO, the mag ballast is reliable and lowers cost.

Thanks Quasi!

That was more info than I expected but very much appreciated. I initially was thinking about snagging that 12.1 inch when it was at $250. At $199, i can't imagine not buying it. Especially since you have such detailed photos/sketches/instructions for this panel on your mini-haas plog.

I guess I didn't realize I needed a split-configuration to do key-stoning, but now that I look back at some key-stoning posts, it makes sense.

After looking at the focal calc snap you posted, I don't really understand how the 220mm focal length fresnel plays a part in the distances. You recommended getting the 220mm and the 320mm from johnzo. I'm assuming that the 220mm fresnel would be placed between the light and the lcd and plays no part in the resulting distances?

I would really like to get as much screen as I can. If I change the 320 triplet to a 265 triplet, my diagonal goes from 110" to 135" with a smaller box.


I found the 265mm triplet on the diy projector kits site...which mentions to be used with the 330mm fresnel.
Are there any problems with shorter focal-lengthed triplets in this setup?

Thanks Bevo. And what do you know, with the calculation I gave above, it turns out to provide a screen that is 116" wide, 70" high and 135" diagonal. My ceiling is 87" high minus the 70" screen and there are 17" of space to raise the screen off the floor. nice.

You are correct about the 220mm rear fresnel placement. Just keep in mind that your lamp will need to be 200mm - 220mm from the rear fresnel. You can read more about split optics in the LL Wiki.


If the triplet you're thinking of is the 265mm, 80mm diameter triplet, then that should work fine. It's best to keep the FL of the triplet close to the FL of the front fresnel, but plenty of people build long throw projectors using LL's Pro 650mm front fresnel and either the 500mm or 450mm triplet. If it works for them, it should work for you. Great find on the triplet. It's got a larger diameter (I think - my triplet diameter is only 60mm) than the 320mm I suggested.

Also keep in mind that you'll want to design your projector so that your triplet and lamp have about an inch of travel (forward and back), for tweaking purposes.

Alright, I've purchased the 12.1 panel and it's in the mail, so there's no going back now. I suppose I will start a Plog once I get all the items. Which brings me to my next question.
Quasi, I'm going off of your recommendation on a bulb. I'm looking for a 250 watt MH. How does this look?
HQI-DE250.NDX 64374

It doesn't have any specs on that site, but a quick google of the part number(HQI-DE250/NDX) results in this(PDF)


Then I noticed the HQI-DE250/DX on the above image at atlantalightbulbs.com for $59 vs $33 for the NDX.

Would you be comfortable with either of these two 250w bulbs? And if so, which one? Would the extra $26 justify the 8 additional CRI and higher CCT?
Oh and btw, the prices for these bulbs on the atlantalightbulbs.com are way cheaper than other sites I've seen.
$173(NDX) at Goodmart.com
$174(DX) at servicelighting.com
Has anybody purchased from atlantalightbulbs.com before? I'm worried they are too good to be true.

Wow, now I just found the DX interlight.biz for $29.10. also mentioned here.

I think I might have just answered my own question. Any recommendations of ballast for 'M80DR'? I've read that an M80 will work or an S50.


Thanks in advance.

I would definitely recommend the HQI-DE250/DX. Great find on the second price listing! You might want to buy two - in case one arrives damaged and/or so you'll have a backup lamp.
It's strange that the first vendor you linked to showed the lamp with a 4900K temperature, while the second vendor lists it as 5600K. The PDF spec sheet lists it as 5000K. You're always better off going with the highest CRI rating within the 4000K - 6500K temperature range (Best Bulbs Chart).

Hopefully, the manufacturers will find a way to bring down the size of the 250W ceramic metal halide lamps. Otherwise, I'll have to go the same route you chose.

Are these what you are talking about?




Yes, that is large 9 3/4" by 2 3/4". But it still isn't as good as the HQI-250/DX.
DX250 vs CDM250
CRI: 93 < 85
CCT: 5000k < 4000k
Lumens: 20k = 20k

Is there something else about ceramic that is desirable? I see that the life is about twice as long 20,000 vs 10,000.

I also found the Philips MasterColor Ceramic Metal Halide CMH250 have better specs, but only found them for sale here(you have to scroll way down for cmh250).

PDF from GE site

I fell in love with the CMH lamps after reading this thread. I've been pretty happy with my 150W CMH and I'd rather not go with an HQI, if I don't have to.

I have seen those lamps you posted the links and specs for, but the glass envelope is way too big (in my opinion). And you can't use them with the Pro reflector. You'd have to fashion your own reflector out of a bowl, or something. It might be small enough to mount correctly in a 12.1 LCD projector, but I'm holding out for better. I, personally, won't buy a lamp with a CRI lower than 90. Like I said, hopefully the technology will catch up and they'll be able to get a double-ended or G12-based lamp out, soon.