ok ive finally decided to build a projector, but have a few questions EDIT: no I don't, all answered thanks guys

EDIT: here are the things i have so far:

150w double ended ceramic metal halide bulb with RX7s holder, colour temp 4200k
150w electronic ballast made by Tridonic (excellent e-ballast for ceramic bulbs, quite expensive though)
180mm triplet
120mm condenser fresnel (in the mail)
190mm collector fresnel (in the mail)
88mm diameter 113 FL pre-condenser
Reflector
ordered 7.2" wxga LCD with pixelworks controller from johnzo
Tempered glass 4mm thick
2 80mm fans moving 32.11 CFM of air at 26.0 dBA
Box 1/3 built

im starting a projector with the same lcd

just like you, I have no idea what light source to use. Ive thrown out 400w MH because it is to big, especially the ballast. my plan is to make this projector as comparable in size as possible to a commercial one.

My other light source options:
1. leds... cree q5. the optics will probably only allow me to fit about 24. they are 228lm each=5472lm -- http://www.dealextreme.com/details.dx/sku.2394
-or, ssc p7, they output 900 lm each, but are a lot more expensive... I would end up getting 4x as many lumens, but spend almost 4x as much

2. xenon hid car kits: a 50w kit will provide me with 2 bulbs each producing 4000lm at 6000k or 4500lm at 4300k
- http://www.lumenlab.com/forums/index.php?s...4175&st=100 here is a topic with 35 watt xenons and good results
-ebay link I understand they are killing you with shipping, but even with that price this beats most 35w kits. Arrange a couple of these with a good reflector and it could turn out good
-I like how small the arc length is on these

3. luxim plasma bulb: ruled out because after contacting luxim, they told me it will cost over a grand if I buy just one with all the electronics.

4. small MH. Im not sure how big the ballast is for a 150w, or how much it will cost. I havent looked into this option yet, because I'm assuming it will be to big for my liking.

This doesnt really answer any of your questions , its my brainstorm of lighting options.

Godspeed fellas, Im really exited to watch your progress.
I know its kind of oversimplifying but the 150w halide should be as bright as an evo, or other commercial single LCD PJ.
And thats pretty darn bright


Good luck!

I think im going to go with LED's too actually for the same reasons as you jimbo but im going to buy 500 (using 450, 50 for mess ups) 10mm mega bright LED's and mount them on a board in 2 layers. LED specs are:

260,000 - 280,000 mcd
3.4 - 3.8v
100mA
color temp 7000k
angle is 40 degrees which i know is big but i emailed the guy and he said he can get the same LED's but with an angle of 15 degrees, which do you think would be best?

I used the mcd to lumen calculator and for the 40 degree angle they give out 106 lumens each, now if i use 450 i would get a total lumen output of 47,700 lumens, even if i only get 0.5% of this light on screen its still 238.5 lumens which is pretty good.

EDIT: SCRAP THAT I AM CONTINUING WITH CERAMIC METAL HALIDE

In my 7" build I am using the s15 kit and a 50 watt mr16 bulb (yes a 50 watt) I think its brighter than my 15.4 with a 400 watt I know I dont understand why either but it is to my eyes

I think you will be just fine with a 150 watt halide for your build. Okay better than fine it will work great unless you are trying to get results of a 575 watt.

Those leds don't give out that many lumens...
3.4v at .1 amp=.34watts that would make the efficiency of each led 318 lumens/watt... that would have a better luminous efficiancy then anything so far

Look into cree q5's or ssc p7's on deal extreme or kai domain



How big are you projecting? Is this with a portable dvd player? Halogen light?

You can read in my 7" plog it started out with a 250 watt OHP bulb and yes it is a portable dvd player. I got sick of the short life the OHP bulb and thought the mr16 looked the same but the highest watt I could find was 50 so I stuck it in there the color is not optimum but I dont care it looks good to me and the bulb last like 2000 hrs and you can find it any store for like 5 bucks and no ballast is required if you get the 120volt ones they do have 12 volt AC one that do require a ballast thats what I have.

do you guys know where i can get a fresnel lens that will fit my LCD (7.2") and has a very short focal length around 120mm? i know i can put 2 together to reduce the FL but i dont want to lose any light so would rather just have one.

Thanks

my infocus litepro 550 is perfect for this 7.2" beauty..it has a 8.4" (4:3 aspect ratio) single lcd in it now and a 400w halogen light engine using a tiny bulb. I want to keep the optics but replace the entire lighting/cooling/lcd system. It would be baaaad but I still don't know what would be a suitable light replacement. The old one supposedly gave off 14,000 lumens of orange light.

how much room do you have? What kind of reflector is in the 550? might be difficult to just throw another light in there with existing optics (reflector, precondenser(s), etc.). I'd say if you could fit it in, and cool it, the 7mm arc and 49000 lumens of the 575w hmi would work nicely Of course, the 16000 lumen double ended 200w lamp might be a better match (but too expensive in my view $130 or more compare to $80 for the 575w hmi).

another member started looking into it here:

http://www.lumenlab.com/forums/index.php?s...st&p=265800

basically I could fit a lamp that is under 20mm in diameter with no modifications, and a lamp that was 25mm in diameter or less without having to shave on the precon/reflector. Now the existing reflector/precon I know are made to handle some serious heat because that little halogen bulb that is in there is crazy hot and the fans in there didn't seem to move much air at all. For this reason I think any sort of MH lamp that can fit in the space between the reflector/precon will be much cooler than what was in there and I'll wire up some better fans that push more air as well. The existing lamp is 14,000 lumens and I'm sure the older lcd panel in there isn't as transparent as the 7.2" will be...I was satisfied with the brightness before but anything that might be brighter/cooler would be a bonus.

the only concern I have now is the cost, as it would probably run me something like $500 just to get the 7.2" kit and a new light kit .

575w HMI bulbs can be found on ebay for $75 (GE) or $35-ish (Generic... with shorter life... about the same cost per hour).
The ballast is the tricky part... an s51 ballast can be modified to run it, or you can get an e-ballast from a number of overhead projectors. Do a google search on '575w hmi ballast' on lumenlab, and you should get the threads with all the info for either. I bought a dukane 682 overhead projector off craigslist for $100 that includes the bulb, ballast and some optics if I choose to use them. I also saw a dukane 680 go for $34! plus shipping on ebay the next day. If you can find one of the following models of overhead projectors in working order, it gets you the double-ended hmi bulb (21mm diameter of capsule at arc), the e-ballast and socket: Dukane 670, 680, 682... The 3M 9850 has the single ended version which would most likely not work in your application and the Elmo solar deluxe has a finicky ballast (not sure if it is double or single-ended). The dukanes come up regularly on ebay, and have sold for between $34 and $130 recently with $40 shipping on average. might be a good option if you can live with the higher bulb replacement costs ($75 for 750-1000 hrs).

cheers!

thanks for the suggestions, but I'm trying to stay away from so much heat..

I'm going to start a new thread. I apologize to the OP, I didn't mean to eat up this much of your thread.

ok so the ballast i have purchased is made by Tridonic and is specifically designed for the CDM range of bulbs so should work perfectly.
its a little pricey, but id rather have something thats going to work well with the bulb and last a long time, plus being in the UK there arent many options available

ok do you think this is sufficient cooling for the box?, the two fans at the bottom are blowing cool air in from outside so will have vents underneith them. sorry for the poor artwork.


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Is that the side view or top view? It looks like a side view. Are you mounting your lamp vertically?
If you're only using a 150W lamp, you only really need the one fan at the rear (I would recommend the top one) of the enclosure. One air intake slot between the LCD and rear fresnel should be fine.

I've been running my projector for months without using any fan at all - but I don't recommend it.

thanks for your reply, sorry the lamp is the wrong way round is supposed to be on its side. i got my ballast today an electronic ballast but i am slightly confused, with an e-ballast you do not need an ignitor correct? but when looking at the data sheet it suggests i need one? or is just telling me that the ignition voltage is 5kV so showing a symbol for an ignitor, (if that is the symbol for an ignitor?) heres the link:

http://www.tridonicatco.com/kms/media/uplo...1_single_en.pdf

Look at the wiring diagram at the bottom of the page.

Does that mean i need an ignitor or can i plug the bulb straight in to the ballast?

That's not an ignitor, that's your lamp.
I think that's the symbol for a mogul base.

ok thanks, here are some photos of bulb and ballast.

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Call me strange, but these are some of the sexiest lamps I've ever set eyes on. I think the only lamps sexier than these double ended lamps are the single ended G12 base lamps.
Have you found out where you're going to get the sockets for the lamp?

id have to agree with you about these lamps although i prefer the double ended one more (i like symmetry ), i ordered the RX7s base from another site along with a UV/IR filter and a 180mm triplet.

ok this may sound like a stupid question, i was doing some testing with a portable tv with 3" screen and my triplet and found that the closer you get to the projection screen, the larger the distance must be between the LCD and the lens, but the futher back i go i.e. to get a larger projected image, the closer the lens has to be to the LCD to get a focused image, now im not using any fresnel lenses in this test, will fresnels stop that or will i need to create a focusing mechanism for my triplet?

EDIT: NEVERMIND I GOT IT ALL FIGURED OUT

Some pictures of construction of the box.

Used floor edging trim to get the rounded edges.

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pieces loosely stuck together with blue tak just to show the basic shape

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quarter round trim..nice .

do you know the diameter of that 150w bulb?

24-25mm diameter

ok small update glued the box together, put a lid on it, recieved my pre-condenser lens in the post, and bought a reflector in the form of a spoon and just ordered the 7.2 wxga kit from johnzo!
Precon specs: 88mm diameter 113mm focal

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some photos of the bulb working. This ballast is brilliant no flicker, restrike time is about 4 minutes, does give out a bit of a buzz initially but fades away to silence within a couple of minutes.


Bulb on, my camera is rubbish so i cant really show the bulb on that well

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Cool down

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Some photos of the light box and how i made it.

1. Find an old tin box you dont want and cut out the bottom of it:

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2. Measure out size you want the box to be and mark off the bend points. Cut around the edges neatly:

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3. Bend at bend points using an edge like a table or something, use a piece of wood larger than the metal to push the metal over the edge and bend it applying even pressure. And here are my results, i will cut out the holes and put the pre condenser, reflector and bulb in tomorrow:

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Very nice work!
You might want to add a bottom to that lightbox to prevent the wood underneath the lamp from scorching - like the one that johnzo sells.

thanks for your comments, i wont need a bottom to this light box, as inside the projector box, i needed to raise the light to get it in the centre of the box so i made a small shelf out of aluminium so as not to burn the wood.

What are the dimensions of internal part of the box enclosure? Don't forget with the 7.2 wxga you would need to make extra room on one of the sides for the ffc extension. It sticks out about an inch or so on one of the sides. I don't know if the cable can be folded and still work or not.

I was just going to ask what are the external dimensions of that box? HxWxL

FOR SHARP 7.2 INCH LCD

Where could one buy those fresnel, triplet in the photo. That looks real nice.

Dimensions:

External - 415mm x 215mm x 150mm
Internal - 405mm x 205mm x 150mm

Im not using 2 180mm fresnels i have a 160mm condenser fresnel and a 190mm collector fresnel. I do have the 180mm triplet though. Not sure where to get 180mm fresnels from but i know where to get the ones i have

Construction of fframes for fresnels and heat shield:

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ok small update i have the light in the box with condenser lens and refelctor (i will post some photos when my camera has batteries ). On the LCD side, i have heard that sharp LCD's have a mirror finish on the back, is there a way to remove that layer or should i just leave it alone?

I tried picking at the corners to see if there were any removable layers. I wasn't sure if there were anymore and then decided, that this lcd wasn't worth risking.

any updates to this? i've been out of the loop for a few years and after going to the movies last weekend...i have to say i'm very much in the mood to build me another projector where people won't be talking the whole movie.

very interested in this thread though! good work so far man!

...people talking, babies crying, phones going off, feet on the back of your chair, paid parking, $7 popcorn, $6 sodas, and that sticky stuff on the floor which is probably the cause of that weird combo smell of vomit and febreeze.

...am I the only one missing something?

... Nope, I think that we are all missing something here... wonder what movie caused this reaction????

My vote goes to Beverly Hills Chihuahua

sorry guys, i know it's been a while since i updated this thread.
In the end i managed to get a picture with a cheap LCD i had lying around, it was faily bright and the picture was pretty good, but i didnt have time to finish it being a student and all. So i decided to stop, sell the parts i had, and bought a commercial projector.
I may start a new project soon for the summer when all my exams are done
Thanks for your interest!