Home made projector!

[Chernobyl]

Hi guys, thanks for the support.
It shall be so, one big manual coming up!


There is something I need to bring to your attention.
The LCD seems to have suffered some form of non permanent burn in from a web based game I have been playing!!

I decided to use a blue theme on the webpage and after a while noticed a couple of lighter coloured lines across the left of the screen whilst playing a movie. I put this down to a smudge or an internal reflection from the OHP for a few weeks until the lines became a little brighter and noticeable during video playback.
Today while inspecting it I noticed the lines are in the LCD

I loaded different colour windows backgrounds to see what colours appear to be affected. Using red, green, blue, white and black showed no sign at all of the problem so tried some other shades and found some exhibit the marks in varying intensities.

Its not a showstopper and has got me thinking how it could occur.
I imagine it is a UV based problem as this has been expected. It first appeared a short while after changing the web colour theme from red to blue.
As the lighter lines have appeared directly underneath 2 blue bars on the webpage, they start exactly where text on the left ends and finish when the blue bar stops on the right, I am thinking that the Blue bars allow UV light frequencies to pass into the LCD and traverse sideways into neighboring LCD cells below??

The UV effect was first demonstrated while using the original bulb and removing the glass. A big red circle appeared on the LCD passing through the location of the 2 lines that have now appeared.

The faded lines seem to go away over time but this does hint at damage being caused. (I can barely see the lines after 10 hours of changing the web page theme back to red, but new ones appear where there is blue for a period of time)

Moral of the story: Put the glass back!

I have attached 2 photos, the first showing the 2 faded lines, the second showing they are gone 10 hours later but with a new faded line lower down, left by the bottom edge of blue window. Both pictures are the same background colour taken at different times of the day. (the camera does that!)
The Glass will be replaced tomorrow before I switch it on. This will give proof if the glass does help.


Note:
This will not apply to OHP's with a cooling layer/cold mirror. These should be safe from the problem if you want to remove your glass.

[Chernobyl]

Originally Posted by flibble

Thanks Chenobyl A very informative and helpfull reply. I'll try and make sure I've got a triplet lense and see if I can obtain one of them there bulb kits. That german distributor you mention does seem to be out of stock though. However, he does do UV shield glass, so I guess if the 400w bulb came in, I could proberly get that and the glass supposedly certified to shield UV.

Yeah the German supplier rarely has stock, its a shame.
I agree with your plan, 400W and UV protection, just the ticket.

I found out the other day that this bulb has mains spike protection.
The lights in the room flickered and the OHP bulb went off. I left it 10 mins and it still wouldnt turn on so assumed it had blown. The next day, it worked like a charm again.
Moral of the story? Use a mains filter

[Chaz]

Hey Chernobyl. Great job on the projector! Naturally I'm going to give it a go. I'll be starting some time next month once I have the cash to get started. I seem to be the only person with a half decent camera, I've got a Fuji F700, and full sized tripod. It takes 3 megapixel photos and can interpolate up to 6 megapixels. It also takes high quality videos - 640x480 @ 30fps. So I look forward to showing off my hopefully successful creation!

I plan to use a 3M 9550 OHP (400w), Iiyama E380S 15" TFT Monitor (Same as Chernobyl's) and *possibly* an upgrade to metal halide, but I'll see what I think once everything is up and running.

[Chernobyl]

Thanks and great stuff, I look forward to some decent piccies
I really like the Iiyama LCD, a good choice for 1024x768.

Be aware the 9550 bulb life is 50 hours!
Other than that it appears to be a very good OHP for the job.
I would like to see the insides of the 9550. It has a cooling layer and I'm not sure how easy it will be to fit a MH bulb.
Can you get some photos up of the internals once it arrives?

Cheers

[Chaz]

Wow. Not a single post since almost 2 months ago? Well hopefully I can revive things. I've finally got the cash (and bags of free time) in order to get going. I've bought the E380S, £99 including shipping! Bargain! It should arrive tomorrow.
No OHP yet, I probably wont have it until some time next week. Expect plenty of photos/videos/etc!
Is everything still working nicely Chernobyl?

[Chernobyl]

I must apologise for not writing the Manual yet, I'm discovering more things all the time and will hopefully be building a custom made box with 17" LCD for my dad some time soon. This will be the 'real' home made projector!


Hi Chaz, glad you have returned!
Brilliant purchase, I look forward to your results.
One thing I have discovered in plenty is there are good and bad lenses in OHPs. My lenses are OK for 1024x768 but wouldnt be quite good enough for 1280x1024. Reason being is that focus isnt uniform across the whole picture.
I find the best average between all screen points which looks really good with 1024, but any higher might look a little blurry in places.

Chaz, try and test drive an OHP before you buy to see how well it focuses. The 3M 1750 (mine) is a fine choice.

Some issues to be observed. Do NOT remove the OHP glass.
The minor damage caused to my LCD while running the LCD with no glass under it is still present but is very faint. It sometimes looks more pronounced, other times almost disappears. This seems to be linked to room temperature, the hotter it is the more pronounced the effect.

Only real scare I had was with a small power cut. The bulb cut out and wouldnt come back on. Next day it was perfect again. It seems there is protection in the bulbs and it works! It would probably have worked fine if left for 15mins, I assumed 5-10mins was enough.

I haven't changed the temporary setup inside the OHP of the lenses, bulb placement etc as it works soooo well. The glass triplet (edit: this is the condensor not triplet) lense above the bulb is still held up by kitchen tin foil, lol. The new bulb is very resiliant, and even when the Lense was left resting on it for a few days (I kicked it oops!), it suffered no ill effects. I didnt even know!

As for how well this works....
I am blown away STILL, every time I watch a film, TV series, play a game...
The 250W MH bulb has got brighter and brighter. I have the curtains open today on the hottest day of the year so far and I can see everything on screen clearly. The colours are awesome. I thought they would look faded being blown up to such a big size screen.
I've never watched so many films. Couple this screen with a decent hifi, the effect is tremendous

I'll be away this weekend and may not reply again til after.

cheers spky soon.

ps if you want any photos, do ask, I'm happy to post them.

[Aedan]

Originally Posted by Chernobyl

Only real scare I had was with a small power cut. The bulb cut out and wouldnt come back on. Next day it was perfect again. It seems there is protection in the bulbs and it works! It would probably have worked fine if left for 15mins, I assumed 5-10mins was enough.

Yeah, MH bulbs have a lot more protection built in to try and prevent them from exploding. I take it you're using an "O" type bulb then, or an "S" type bulb?

[Chaz]

Well, I placed a bid on an OHP (9550) on ebay, for a very high amount because I didnt think an opportunity like this would come around soon - and I still didnt win. It went for £137, plus £16 shipping. And the auction didn't even say if any bulbs were included.

I'm starting to get pretty worried about this 50hr bulb life. It's gonna end up cheaper to run a metal halide, isnt it? And it was a damn hot day yesterday, if your projector can be perfectly useable with the curtains open on a day like that, how can I not be tempted?

I'd still like to go with the 9550 OHP, rather than a different model because I'll be changing the internals. According to measurements of the illuminated glass area, this TFT will actually fit on with 2.5cm clearance above and below the LCD. Doesnt that mean there wouldent be any corners clipped off?

Thanks for recommending the E380S - it's a brilliant little monitor, I'm using it to type this post. Luckily I'm not tempted to just keep it and scrap the projector idea, it's too small and a max res of 1024x768 makes windows quite big and ugly in comparison to the 1280x1024 I'm used to. Works wonders in games though!

So it looks like it may be a while until I can get my greasy hands on a suitable OHP. Unless you have any other recommendations, Chernobyl?

[Chernobyl]

Originally Posted by Áedán

Yeah, MH bulbs have a lot more protection built in to try and prevent them from exploding. I take it you're using an "O" type bulb then, or an "S" type bulb?

Mine is an O type. It has a glass sleeve around it to protect from explosions.
It seems the S type dont have this protection which would make them a bit of an uncertain thing to use.

the bulbs that around now are bang on for the job.

[Chernobyl]

Originally Posted by Chaz

Well, I placed a bid on an OHP (9550) on ebay, for a very high amount because I didnt think an opportunity like this would come around soon - and I still didnt win. It went for £137, plus £16 shipping. And the auction didn't even say if any bulbs were included.

I'm starting to get pretty worried about this 50hr bulb life. It's gonna end up cheaper to run a metal halide, isnt it? And it was a damn hot day yesterday, if your projector can be perfectly useable with the curtains open on a day like that, how can I not be tempted?

I'd still like to go with the 9550 OHP, rather than a different model because I'll be changing the internals. According to measurements of the illuminated glass area, this TFT will actually fit on with 2.5cm clearance above and below the LCD. Doesnt that mean there wouldent be any corners clipped off?

Thanks for recommending the E380S - it's a brilliant little monitor, I'm using it to type this post. Luckily I'm not tempted to just keep it and scrap the projector idea, it's too small and a max res of 1024x768 makes windows quite big and ugly in comparison to the 1280x1024 I'm used to. Works wonders in games though!

So it looks like it may be a while until I can get my greasy hands on a suitable OHP. Unless you have any other recommendations, Chernobyl?

I really wish I had more experience
As I've seen only one OHP running with an LCD, its difficult to know which have a uniform focus. I'll be reading through some forums soon to see what I can find for you.

To me, a 50hr bulb life isnt managable. I pity anyone who has to replace bulbs that often! I havent had to change bulb now for months and even forgot the old days having to find bulbs cheap. The MH system is very worthy.

The screen doesnt quite fit on the OHP left to right, the top and the bottom fit on with ease.
Glad you like the E380S, I do agree, its great!

A word from the wise, you may need a proper screen to get the brightness I do. I cant test my projector on a wall as I dont have one, they're all wood!
Search ebay for "Screen Material". Theres a chap in the US selling some that sounds really good for the job. You stretch it round a frame, its washable and $42 to have it delivered. The cost of the material is pretty cheap too.
I'm getting some as soon as my other projects stop leaching cash!

Good luck finding an OHP. If you want to know about any you find, do ask and I'll find what I can.

[Chaz]

Well - it's excellent news. I finally got my hands on a 9550! And it should arrive by Friday. So, expect lots of images and videos by then! I cant wait to get started.

[Chernobyl]

Ace one
Looking forward to it too!

[Chaz]

Its here, and goddamn it's bright! I'm currently taking apart the TFT, having a bit of trouble though... I'll get through it. Pics soon!

[danrok]

Please do post pics! Thanks Chaz.

[Chernobyl]

Go Chaz!!

Please observe antistatic precautions when handling the LCDs innards.
I coated a piece of cardboard in tin foil and used that as my workspace.

[Chaz]

Wahey! It is up and running. I had a few minor problems along the way, the biggest one was that I couldent actually get the main monitor case apart! Turns out I had missed a screw! D'oh!

http://www.infernolabs.co.uk/projector/box.jpg
Handle with great care! My 9550 is in that box!

http://www.infernolabs.co.uk/projector/ohp.jpg
Wahey - there it is.

http://www.infernolabs.co.uk/projector/diy1.jpg
http://www.infernolabs.co.uk/projector/diy2.jpg
http://www.infernolabs.co.uk/projector/diy3.jpg
http://www.infernolabs.co.uk/projector/diy4.jpg
Various stages of dismantlement.


http://www.infernolabs.co.uk/projector/oops.jpg
Ready to power on... Damn! Forgot to turn the res down.

http://www.infernolabs.co.uk/projector/wahey.jpg
Wahey! The first photo of it in use. This was taken at about 4pm, with the curtains (yellow curtains) closed.

After several optimisations, gamma tweaks, moving things around and all that, here's my final result:

http://www.infernolabs.co.uk/projector/cs.jpg
http://www.infernolabs.co.uk/projector/hl2.jpg
Not bad although I say so myself! After using the 'clock' function on the TFT, and playing with ATi's screen shrinking tools, as you can see there is very minor croppage going on there. There is no cropping at all on the top, and only small triangles taken out on the bottom.

I've measured my projection size - 90 inches! That's 7.5 feet!

And of course, a video is in order too! However it doesnt do the projector much justice at all. The whole screen was visible (brightly) and it was still easy to see inside the dark tunnels, honest!

www.infernolabs.co.uk/projector/CS.wmv

---

Now, it doesnt work perfectly. I need to get myself a proper screen, I think on Saturday I'll get myself a large piece of hardboard and paint it matt white.

Also, there is a fuzziness issue. The image is slightly blurred around the edges, it looks out of focus. I can focus the OHP how I like, if it's focussed on the centre of the screen, I can clearly see the individual pixels, however around the edges it's quite a bit more blurred and distorted. I thought the triplet lense mounted in the 9550 was designed to stop this?

I took antistatic precautions. I got a very long piece of wire, tied it to my wrist, and tied the other end to a nearby radiator. What I didnt realise was that I didnt have any wire cutters nearby to cut myself free once I was finished! I had to call someone downstairs so that they could go into the workshop and get me some, so I could free myself!

---

Anyway, overall I'm extremely pleased, and I dont think I'll need to upgrade to metal halide, unless the bulb time gets on my ass. I've got it running in economy mode and it looks exactly the same as the standard brightness. Thank you very very very much to Chernobyl, Cesium, and everyone else who did a great job on their projector and managed to motivate me to build my own.

Oh yeah, I just noticed I havent taken any photos of the Projector itself! I'll take those tomorrow.

[Chernobyl]

Brilliant, that looks the part!!

About the focus issue
I use an average focus between everything on the screen. Needle sharp focus has a digital look about it, so in all honesty its no loss at this resolution to have it slightly defocussed. I'm interested to see if you are satisfied with a slightly off focus too. All my previous photos allow you to see how good a slight off focus looks here.

The focal lense is the top adjustable height one. That could be replaced with a higher grade lense if needed. This is something I really want to try in preparation for a bigger higher res version.

By observation, the triplet lense inside the OHP passes more light to the LCD and distributes it more evenly. I didnt notice a difference in the focus when I removed that lense, despite the advertising blurb for the OHP saying it improves clarity.

If you can block as much light from the OHP as possible from getting into the room, the contrast ratio will improve (along with bin bags over the windows!)

Lol about the tying yourself to the radiator. You seem a bit good at the tying up biz

Looking forward to seeing more results

[Rondog]

Sweet as!

Too bad it cant be mounted to the ceiling to be put out of the way. Oh well, a great engineering achievement. :thumbs:

[Chaz]

After using the projector more and more I am thinking it would be nice to switch to MH. Having to rationalise and worry about bulb life all of the time the projector is turned on isnt really a nice feeling! I could do with the extra brightness too, you (Chernobyl) seemed to get quite an improvement.
At the moment it's very difficult to read anything around the edges of the screen, for example in Counter Strike it's very difficult to read the 'who killed who' information, especially which terrorist got killed, because his name is in red. Everything looks smudged towards the centre of the screen. Maybe theres a problem with one of the lenses, I dunno.
Watching films is great. because the OHP is mounted on a desk I can sit right infront of it, and have the whole screen fill my view, without casting a shadow. However because I've got a wired keyboard and mouse, I have to sit at the PC while playing games. I think it's time to order a wireless kit!
Anyway. I'm getting this screen tomorrow, should improve the colours. If I hold a piece of high quality photo paper infront of the screen the brighness is slightly better, but the colours are certainly more accurate.

I looked on ebay and found the bulbs you said you used to buy, they appear to be the same as the ones my OHP uses. Just a thought, if yours lasted 270 hours on economy mode, why wouldent they last just as long in my OHP?

Right, onto the photos. As you can see, I'm using an 80mm fan for cooling. The OHP might have a 'cooling layer' but I'd rather not take any chances. The LCD panel now feels lukewarm to the touch. The three sheets of paper are to stop light escaping. There were some lines of light coming out of the front of the OHP and escaping onto the projection area, at first I thought it was the LCD packing in! The other two bits of paper cover up the rest of the uncovered glass.
As you can see it's a bit of a temporary situation at the moment, the electronics being held up by stacked cardboard boxes and all. I'll probably make a proper box to hold them in some time.

Any suggestions for improvement?

[Chaz]

I got the shock of my life today. I dismounted the LCD from the OHP to clean it, put it all back together then powered on. Broken lines across the screen. I skipped a heartbeat, I thought I had already broken it. After shuffling the LCD around a bit it flicked back on, so I thought it must be a poor contact. I removed the metal plate from the main circuitboard, and saw that one of the two data connections, linking the main circuitboard and the additional smaller one, had come unlocked. I put it back in, locked it down, and thankfully everything works great now...

Today I painted a screen onto the wall, and it has made a nice improvement (see attached photo). Everything is slightly brighter, but the colours are obviously far better, almost perfect. In CS I can now pretty easily read the 'who killed who' information at the top. Also I stapled - yes, stapled - binliners onto my curtains. With them closed its lovely and dark, dark enough to use windows or play any game.