I thought I might post some pics of my final results. This is a 19" unsplit widescreen projector with the pro-lens and 550 and 220 fresnel combo. Very happy in the end and thought I should give back a little. Click on images to open larger link. (link to outside image host.)

The most important part in engineering my projector was COOLING the 400watt Ushio bulb.

I have a Scythe S-FLEX 48cfm (silent) fan blowing in from the front across the bulb tube. Then inline on the back is a 110cfm fan exhausting the hot air out. The exhaust fan is more powerful than the input fan to keep the box with negative pressure, so the upper cooling circuit works, and no matter what hot air will not billow up to the LCD. My running temps are 100 farenheit below the XL-10 and 78 farenheit between the LCD and 550mm fresnel.

Air is drawn in from the back vent, then down through the maze of 'shelves' holding the LCD then the 550 then the 220 and finally through a hole in the XL-10 in the corner and out the back. To benefit the cooling further, I kept the magnetic ballast outside of the box (runs very hot) and cut a hole behind the projector so the exhaust vents out into another room (furnace\laundry room)

Focusing solution was to use a 4.5" toilet flange and wrap the outside of the lens in wide electircal tape to friction fit the lens in place at focous. Long end of the lens facing into the projector box. I've seen some remarkable solutions to the focusing issue but my motto is KISS. Only need to focus it once anyway.

Extreme closeup of Player menu (shaky hands)



Guts of projector



Cooling curcuit (holes sides alternate between layers) eg. top layer on right, middle on left, bottom on right etc...



Here is my unsplit measurements with a 19" widescreen monitor, LCD first then 550mm condensor middle, 220mm on bottom



projected picutre size of 80" x 50"



Test shot for comparisson



Hi-Def National Geographic Wallpaper (no hi-def devices available)



Distance from rear 220mm fresnel to bulb top of arc tube is 20cm with Ushio SD400

Shot from LOTR 480P on pause.




Basically anyone can build one of these. My advice is to make sure your monitor is HDCP enabled (DVI-D input) and will work with a HDMI to DVI-D conversion cable. This will let you hook up any DVD\Blu-ray player with an HDMI output to it easily enough. My monitor is the 19" LG, no FCC issues.

http://ca.lge.com/en/products/model/detail...l196wtqbf.jhtml

Treat your LCD like a baby, if you get results as good as many of the others here, you will see any imperfections in the LCD on you wall when done. I've got a few small jaggy scratches that add now and then add 'character' to any scene.

Good luck to all and thanks to those that took the time to write plogs and help us all out!!

Cheers

Nice !
Perhaps a little more detail would be good though.
What are the dimensions of your completed unit?
Any ideas what sort of lumen you're getting at the screen?
Looks quiet, is it?

ps. This is in no way a criticism i think you've done a great job. I'm surprised no one has commented.
Well done.

Oh......I guess I shouldn't that razor blade around my LCD (ooooops) lol!
BTW, great build!


Oh......I guess I shouldn't have used that razor blade around my LCD (ooooops) lol!
BTW, great build!
(missed a couple of words)

The cabinet by LxWxH is 18"X18"x50" from the floor to top.

it is just big enough inside to take the full size of an uncut fresnel in case I want to re-use them in a future build. Since completion I have made a more permanent screen with stretched material over a frame. I added a matte black moulding for around the outside and it looks very good. I must say, it makes 100% difference having a properly sized and bordered screen to view, rather than a sheet of black out on a drapery rod hanging.

The final outside screen size is 86"X551/2" about 95" diagonal viewing area.



We have watched over 50 movies since completed in March of 2008. (We hardly watch any TV.) I also game on it frequently with the WII (ir sensor bar mounted at bottom of screen,) PS2 and Xbox. Mairo cart is great fun when 4 players each get the equivalent of a 42" TV to play on!! No problems to report so far. Rock solid when viewing blu ray material. Help from great people here has made all the difference. LUMENLAB ROCKS!!

Your results are beautiful... I am very surprised, . speechless

Did you AG strip that LG monitor or did it have the glossy type of screen not the flat matt type?

No AG strip. It had the matt finish on the front (side facing the lens)

Thank You...

What was the overall cost for this projector, and were the fresnals expensive for the 19" monitor? Very nice by the way.

The overall cost of screen and all PJ parts was around 800-900.

From memory:

LCD Screen 220
Pro Lens 200
Fresnels 50
Fans 30
Front surface Mirror 70
Screen materials 100
Lamp 75
Ballast 50
Odds and ends that didn't make it to final product ~100
Shipping and customs and sales tax from online stuff (ship to Canada) ~100$


At the time, 19"WS fresnels were commonly available at both lumenlab and elsewhere. I ordered elsewhere because the Pro Lens was always out of stock at LL and no 650 fresnel was available. (550 was used in final build.)

4 things I will do differnently next time.

1. Build out of 1/2 or 3/4 MDF- MDF has inert sound properties and is commonly used for speaker construction. In my home theatre, the sub often finds the resonating frequency of the PJ and rattles it a bit.....

2. Use a HDMI equipped upconverting A/V receiver to do analog video transcoding and all the other heavy lifting. (now using Kworld 1680EX and it has it's drawbacks when playing Wii or PS2.)

3. Build using either a 17"WS or 15.4" monitor, so my PJ can sit further behind the seating area. I would like to sit 1.2-1.5 times the diagonal away from the screen, but at 9 1/2 feet the screensize is alreay 95" ! I guess bigger is better! In my small room we sit 8 1/2 feet from the wall.

4. No tinfoil. It adds no benefit IMO.

Showing off DVD christmas gift. The Dark Knight is awesome. Enjoy. 480P over HDMI-DVI connection. I need to break down and buy a Blu-ray player, instead of borrowing....


Nurse Joker

Boom Boom Nurse Joker


Merry Xmas Everyone.

If you look closely you can see Jaggies from blowing up 480P. Yep, time for HD.

Realize the outside may not be of importance to you - but it'd be nice to see an external shot(s) of the PJ.

great job though, adding to my favs for inspiration. whenever you're really bored and want to be merciful to the lazy and mind challenged feel free to create full spec measurements of your created items so i can simply reproduce what you've made.. Reproduction is the best form of flattery isnt it?

hi HellCommute

i also want to use 19" monitor with div-d input
i am having 450mm quad element projection lens
i want ur help to guide me about the dimentions & focal lengths of the two fresnel lenses which i can use with the 450mm lens

& from where i can buy these fresnel lenses....

thanks ...yogi

what materials did you use for the screen second time around

Hi Yogi, I Don't have any experience with the 450 PJ lens, but the condensing fresnel should have a focal length near that of the projection lens to maximize the focus of light on the lens (a 550 fresnel might be a bit too long in your case.) A 19" monitor was doable back when I built mine, but Fresnels that size are becoming scarce.

Hey McNasty, The screen is a white plastic table cloth material with a felt backing- from Fabric Land. It is very similar (in colour and texture) to some high gain projection screens I have seen and has a very wide viewing angle. There is also the old blackout cloth behind it, just in case some light gets through. (It is not an opaque material as blackout cloth is.)

Hi Fatscreen, I will get some pics of the outside up when i have a sec. Sorry, I can't give you a "recipe" of how I built mine. As with all recipies, you will find the best flavour in something you created from scratch by yourself Actually, there are lots of plogs with far better explanations than I can provide, and I wont presume to even pretend my results are as good as some others out there.

--Given the Lenses I used-- my lamp arc to collimnating fresnel is ~ 21cm, the distance between unsplit fresnels is about 2cm and distance between condensing fresnel to LCD is about 2cm. The distance from the PJ lens to the LCD panel will vary depending on how far away from the projection surface you are, but I worked with a distance of 57 cm (to lens center) while planning. If need be, lengthening the distance is easy with the correct toilet flange applied.

I suggest working from proven methods in plogs, and leave all components in an adjustable state, then fix them in place permanently when you are satisfied.

Good luck.

Hi HellCommute
These are excellent results.

I too am doing a 19" WS straight through projector.

You can see some pics:
http://diyprojector.skygle.com/
http://diyprojector.skygle.com/wp-content/...01/pict0271.jpg

My fresnel on the lens side 650MM, I got this because it actually covered the LCD.

I've just ordered the 550MM fresnel from diyprojector kits.

Did your fresnel cover your entire LCD?

I'm using a 450mm FL Quad element Projection Lens W/Built In Focus Ring and a 650MM frensel. I think I've got a big mismatch there.

I'm having difficulty lighting the entire screen. I'm thinking a stronger fresnel will help.

Was this ever an issue for you?

TIA

Paul

I used a 550 fresnel with a fl500 pro lens with no problems. The fresnel did fit the entire screen (but I can't confirm you bought the same sized lens.)

You can help artificially fix the dark corners by:
1. Adjusting the bulb to rear fresnel distance. ( to find sweet spot)
2. Cranking the "contrast" in your user menu to around 85 or so (assuming the default of 50 is what you are at now.) This will increase the transmissivity of the LCD, giving the overall appearance of a brighter image. This helped me out a lot. Hint: Find the point where cranking the contrast causes the image's brighter areas to wash out and back it off a bit. A static test image is best suited for this. I suggest using the THX optimizer found in the special features of many DVD and Bluray titles to assist.

Many others can confirm the ideal solution is using a 330mm Fresnel for the colimnating lens (bulb to first fresnel distance) to gain a more uniformly lit image. Search for the "inverse square law" for an explanation... But you can use the tweaks I mentioned with good results.

Best of luck. Your plog looks good.

Hi Hellcomute,
Thanks! I'm betting on the fresnel. I've seen some dramatic differences moving the bulb around. But the most telling thing is I can see the image spilling over the back of the lens. I really feel I have a miss-match here.

I think yours should be in the hall of fame. You have some amazing looking quality.

Like you, now that I have done this, I wish I would have started with a smaller LCD, no bigger than a 17inch. And I if I could get it, a 15 inch WS.

Paul

hi jpavery
its yogi
iam also planing to make a pj with the same parts & 19" lcd u r having
the dim corners is happning because lens does not cover the entire light cone
no u dont have a miss match ,try the unsplit configuration with the 19" lcd

try the following dimentions :-
1) 220mm between the lamp & 220mm fresnel
2) 20mm between 220mm fresnel & 650mm fresnel
3) 507mm between the 650 mm fresnel & the 450 mm lens(for 14 feet throwing distance )
the distance between the 650 mm fresnel & the 450 mm lense will vary with the throwing distance

what is the distance between the projector lens & the projected screen

Hi Yogi,
Ok - gave it a try. Never thought of this.

You are correct that the lens is not catching the entire light cone. I never thought of the un-split configuration.

This did make a significant improvement. I'll takes pics tonight to show the full effect.

From projector to wall, 128"
Screen so far is in inches 99W 57H and a diagonal of about 106 (hard to get accurate measurments when measuring by myself.) Note screen is just a bed sheet right now.

One draw back to all of this is I cannot see my entire screen now.

Note: my lens had to be about 420 MM from the 650 frensel. To far forward and it would not focus.

Thanks Yogi - great suggestion and I look forward to tweaking it more.

Paul

Yogi,
I've got some great results. One issue is how do I do key stone correction. Any idea?
Paul

hi jpavery
good to hear that.
can i see some results,
give me the dimentions of the projector & the distance between the components,
try trillting the lcd or the 650 mm fresnel ,this might solve the keystone problem(just a thaught)
r ur image corners brighter now, how is the entire brightness & contrast..

Hi Yogi,
Lets not hijack hellcomutes thread. Please go here

http://www.lumenlab.com/forums/index.php?s...p;#entry3016013

and here

http://diyprojector.skygle.com/

to see the results. I'll answer your questions on my plog here at LumenLabs.
Paul

Hi All,

It's been a while and there have been some updates. I now have a "real" theatre setting. With decent seating and good source components. What a difference. Big screens definitely need big sound!

Components:


Pioneer AV receiver
Sony Blu Ray Player
and a kick ass VCR!!!! LOL

Seating:


Cupholders. Whoever invented these needs a raise. (or at least a slap on the back.)

Screen and Bookshelves:


JBL bookshelves, and if you are counting- the second sub. You want punch, you got it.

Lastly the thing that started it all, our beloved "beer fridge"


The next step is to paint all of the classic (puke) wood panelling a matte grey to clean up the room and make screen reflection less of an issue. While that is going on I will run the speaker wire behind the baseboards. Always looking for tweaks!!

Still working like a top after a year of steady use (4-6 hours per week.) I'll update some time with screen pics of the beast breathing bluray fire.....

Cheers!

P.S. The wife is a projector convert, and now that we are looking to buy a new house in the near future a space for a theatre is definitely her priority! Sa-weet!

This projector has been dissasembled to make a horizontal folded design much light Pegasus' inspiring build. A new thread with pics and details will follow soon upon completetion. The new design will use the same parts (including the 19" WXGA monitor)

Goals for the new build are:

1. Run cooler with less fan noise.
2. No light leaks.
3. Portable.
4. All parts contained within box. ie. ballast and eliminating ducting.
5. Focus knob and assembly with 10cm adjustment range supporting estimated 8-22 ft throw. (for future LCD shrinking)

The cabinet has been made with external dimensions of 18.5"W x 16.25"H x 27" L.

Sneak peak.