Home made projector!

[Chernobyl]

Hi Joe,
excellent, I hope you have fun working it out, thats quite an ambitious project.
Can I ask you to create another thread when you are ready to post as this one will become a little cluttered.

Chernobyl

[fearless joe]

sure thing, it wont be for a few weeks cos of xmas, just had a thought, saw one of those ohps on ebay that has a mirror at the bottom and a light and mirror at the top, duno if that would be any difference??
joe

[Chernobyl]

Originally Posted by Áedán

Indeed you can, but you definately need a screen that will retain the polarisation for it to work well. It would appear that many surfaces will affect the polarisation, leading to poor image seperation.

One possibility would be to use the stereo switching signal to alternately blank the LCD panels, but again, you might end up with bleed through due to the slowish response of the LCDs. Otherwise, you're back to using some kind of demultiplexor/frame buffer to keep the images current. I wonder what would happen if you held off the sync pulses from one of the LCD panels for a single frame?

Can you tell this is something I've thought about a bit?

Áedán, I've created another thread for this:
http://www.aoaforums.com/forum/showt...269#post286269

[Chernobyl]

Originally Posted by Daniel ~

Thanks for giving me a dignified way out Chernobyl! ":O}

[Chernobyl]

Some more tasters using the old smaller screen.
I'll do some more on the big screen soon, promise!

You can see from the cats that some loss of colour was occuring on the smaller OHP screen compared to the monitor. Also the Farcry pics show what was happening to Blue. This still happens a little with the big sheet but nowhere near as bad. This is directly due to how yellow white is. The more yellow, the more blue looks off and the picture seems less bright.

I'm thrilled to bits that it gets a picture anywhere near the quality of my monitor as it is damn good.
Brightness is not as high as I would like, but there has to be a trade off when projecting an 8ft image on a limited budget.
Watching in total darkness is super. I watched Charlies Angels 2 today with the curtains closed and it is still pretty good in the day.

edit: oh yes, pinpoint accuracy in FPS games is fantastic. You can see the guy in the distance, aim, fire, he's gone. Using a sniper rifle is incredibly easy.
A friend complained in CS:S, it seemed to his eye the refresh rate of the LCD wasnt fast enough. As I didnt feel that was true we discussed it and summarised he 'can' see that or it could be that the screen is so huge every tiny movement moves a lot on the big screen and will take time to get used to.

When gaming I try and move the mouse more as it seems theres a lot more to move Odd but true. We'll see how we adapt to it

[fearless joe]

i have an idea, need advise, ok before i said i was thinking of putting two lots of ohp electronics in one ohp, i decided this was silly and came up with a better one, but it is based on one, totallly made up assumption. the thery came from uni, as i do filming there for my corse, we use lighting equipment, as in small halogen flood lights that pump out about 4000 watts,,,,,,,,,, you get were im going with this doint you, get a fallty ohp on the cheap, take out all the electronins and stick a stupidly powerfull, and rellativly cheap flood light in it, you can get 500 watt securetty lights of ebay for £6.99 buy it now, i was thinking getting a 2000 odd watt propper one for a bit more, but i digress, ********THE PROBLEM********** do ohps work on the theary that the light is in the exact right place, and the glass is a lense that directs it perfically in the right direction, (to the top bit) cos if they do this will become a lot harder, but if i can get round this it may make this cheaper to do, before i mention cooling, anyhow anythoughts before i start building??
joe

[Chernobyl]

Yes
Please make another thread

thanks

[fearless joe]

ok i can admit to being stupid, were the hell is the button to open a forum lol
joe

[Chernobyl]

Hi Joe
if you press the 'Forums' button at the top of the page, choose your forum and you will see a 'New Thread' button. Make sure you read the rules, I nearly broke one!
You will find them as the first link in each Forum titled :
"Announcement: Forum Rules Writ in Stone".

Good luck with the project

[Chernobyl]

I took a break from playing with it to get the camera out
Here are 5 pictures of the Milkdrop Visual plugin for Winamp.
The screen is about 8.5ft diagonal (pretending the corners exist).
Any larger and too much brightness is lost.
You can just see my monitor in the bottom right of the screen. To gauge the size, the monitor front is 2ft from the screen. I am standing about 7ft.


While playing around, a dark spot appeared in the center of the screen, SHOCK! It was turned off quick smart. Power had been cut to to the fan.
I thought that was it, another LCD fried, after cooling for a few mins it came back to life as though nothing had happened
It did get very hot too, glad it can cope.

I'm not measuring temps as my CPU cannot live without its probe. Suffice to say the LCD screen is nice and cool with a single silent 120mm fan at 7V blowing above and below the LCD from the side.

I've kept some temp readings made with the old dead panel to see just how hot it would get if touching the OHP with no air gap and a fan blowing from above. The temps I found were around the max rated operating temperature of the LCD. Maybe this method could work, but I'm sure it will shorten the life of the screen.

I'm doing a lot of experimentation with colour settings in NVidia drivers (excellent but infuriating), RivaTuner and ffdshow, hence the slowness in posting any gaming pics etc.
I'm getting somewhere near satisfied with the colour balance and brightness.
Needless to say most of the problems with brightness and colour balance would be resolved with the use of a decent bright screen.
Not bad for a £15 sheet tho!!

Chernobyl


edit: added image 5
no photo can do Milkdrop justice, its simply amazing

[robbie]

You can see from the cats that some loss of colour was occuring on the smaller OHP screen compared to the monitor. Also the Farcry pics show what was happening to Blue. This still happens a little with the big sheet but nowhere near as bad. This is directly due to how yellow white is. The more yellow, the more blue looks off and the picture seems less bright.

I've been giving this some though and you might be able to correct this with some gel's. What color to use? I'll have to get back to you.

[Daniel ~]

I'm using the blue as my desktop, very soothing...":O}

[Chernobyl]

Originally Posted by robbie

I've been giving this some though and you might be able to correct this with some gel's. What color to use? I'll have to get back to you.

haha, I'll have purple cats please.

You have me intrigued, where/how do you use the Gels?

[fearless joe]

chears new therad
http://www.aoaforums.com/forum/showt...771#post286771

[Chernobyl]

Originally Posted by Daniel ~

I'm using the blue as my desktop, very soothing...":O}

Hmmm
thanks for that, it does doesnt it.

[robbie]

Originally Posted by Chernobyl

haha, I'll have purple cats please.

You have me intrigued, where/how do you use the Gels?

Ever been to a concert? Ya know how they sometimes have blue lights and red lights and green lights?!?! Well, they put a gel over the light to give it that effect (not a gel as in a slimy substance) but a semi transparent film.
Rob

[Chernobyl]

Originally Posted by robbie

Ever been to a concert? Ya know how they sometimes have blue lights and red lights and green lights?!?! Well, they put a gel over the light to give it that effect (not a gel as in a slimy substance) but a semi transparent film.
Rob

Ah yeah, I had considered using a filter but it means having a smaller screen to keep the light level up. It may be the only thing to truly correct the balance unless I get a proper screen!
Getting a proper screen sounds more appealing all the time, more brightness, better colour balance, bigger screen. Hmmm
I'll try washing the sheet in a luminous dye

[Samuknow]

I am totally tripping. When I moved from MN to IN in April I gave away a new OHP with 7 bulbs. This one had about a 6 foot diagonal focused projection. Sighs heavily This is why I tell my wife I never get rid of anything...

Great job BTW...

[Chernobyl]

Originally Posted by Samuknow

I am totally tripping. When I moved from MN to IN in April I gave away a new OHP with 7 bulbs. This one had about a 6 foot diagonal focused projection. Sighs heavily This is why I tell my wife I never get rid of anything...

Great job BTW...

hahaha
sorry, must be the Baileys

Yeah I hold a similar philosophy to your wife. I do end up using most of the stuff I keep, it sure does take some space!
Thanks for your support

merry xmas

[Samuknow]

Originally Posted by Chernobyl

I do end up using most of the stuff I keep, it sure does take some space!

I have two large cabinets full of hardware as well as a closet full.

Merry Christmas back at ya and again AWSOME...