I'm using a 3M 9700 overhead projector with a 15' IBM monitor. The light source I have in place right now is the 400w Ushio bulb found at Lumenlabs with a magnetic ballast. I also have a somewhat parabolic reflector jimmy rigged out of foil and cardboard to help reflect the light. I have also built an enclosure to keep out all the excess and ambiant light. Everything is working out pretty good so far. I am impressed with the quality as well as the size...about 100'. However, I would like to increase the brightness of the picture. I am not talking about going into my video card and increasing the brightness through there because I have tried that. This helps the problem but not by much. I wanted to know what would significantly increase the brightness of my picture. I am not sure about fresnell or focus lengths since I am a noob of the noobs and because I am not sure what comes standard on a 3M 9700. All I know is that the bulb is placed at the position (where the old bulb should be) to get the most light.
1) What can I use to physically make the picture brighter?
2) Is there any type of reflector that would be really good that I could find under $10.
Thanks a bunch.
1) What can I use to physically make the picture brighter?
2) Is there any type of reflector that would be really good that I could find under $10.
Thanks a bunch.
well a better reflector will help alot if its a good one but will be hard to find under $10 unfortunetly there is alot you can do to increase brightnes. of course if the fresnel yer useing is older it might be good idea to get a new one ... also a 18" or 22" beseler triplet lens would also help but are expensive --- $75 and up and thats if you can find em
I found something that helped immensely...and it required nothing to buy. For everyone out there...it helps a ton to increase the angle of the LCD on the stage...basically, so that the LCD is not laying flat on the stage. My brightness increased quite a bit with this. However, since I am a perfectionist, is there anything else anyone knows to increase the brightness? Every little bit helps. Thanks
Reflector? Hmmmm......
This is gonna sound a little crazy, but for the price it just might work OK.
Buy a set of cheap stainless steel mixing bowls. If you get a set instead of just one, you will have a better chance of getting one that will fit. Get the kind that are mirror finish on the inside and are as smooth inside as possible - that is, as small a flat spot on the bottom of the bowls as possible. The steeper the sides of the bowl, the more parabolic the cross-section will be.
For example, there is this set on Ebay Brand NEW High Quality 5 piece Stainless Steel Bowl Set , I think that they are a little shallow, some light might escape. But, frankly, it will beat the heck out of aluminum foil.
Maybe there is one in your kitchen?
If you are scientific and can figure this stuff out, go to Anchor Optical Surplus and you can get a radius mirror cheap.
This is gonna sound a little crazy, but for the price it just might work OK.
Buy a set of cheap stainless steel mixing bowls. If you get a set instead of just one, you will have a better chance of getting one that will fit. Get the kind that are mirror finish on the inside and are as smooth inside as possible - that is, as small a flat spot on the bottom of the bowls as possible. The steeper the sides of the bowl, the more parabolic the cross-section will be.
For example, there is this set on Ebay Brand NEW High Quality 5 piece Stainless Steel Bowl Set , I think that they are a little shallow, some light might escape. But, frankly, it will beat the heck out of aluminum foil.
Maybe there is one in your kitchen?
If you are scientific and can figure this stuff out, go to Anchor Optical Surplus and you can get a radius mirror cheap.
If there is no principal mistake in your built, all distances are correct, LCD is set optimally, then there is very little you can do to increase brightness. You could get a precondensor lens, this would increase light output about 20-30%, it's a noticeable difference. You can remove antiglare from your LCD, very risky, some people report they get brighter image after that, I didn't, just a bit sharper image and more vivid colours. You can try to stop all light leaks and internal reflections in the box, that will visually improve image quality. Finally, if you are desperate, you could buy a big, bright lens, but there is no point, as this is insanely expensive (like the "pro" lens from Lumenlab, who buys that?), and you will still have a crappy projector, just a bit better, still no way comparable in quality to a cheap commercial unit, but already comparable in price.
I'm sorry to tell that, but I bet no one in the whole world has built a really bright DIY projector, using these common components. You can hardly reach 200lm output, while 50-100lm is a typical value, which is a shame, but we can't do anything about it, because there are physical rules behind, that we cannot overcome.
And be careful of scam across some forums. If you read quotes like "my DIY projector performs perfectly in all light conditions and beats any 10k$ commercial unit", you should suspect someone is trying to rip you.
Regards
I'm sorry to tell that, but I bet no one in the whole world has built a really bright DIY projector, using these common components. You can hardly reach 200lm output, while 50-100lm is a typical value, which is a shame, but we can't do anything about it, because there are physical rules behind, that we cannot overcome.
And be careful of scam across some forums. If you read quotes like "my DIY projector performs perfectly in all light conditions and beats any 10k$ commercial unit", you should suspect someone is trying to rip you.
Regards
pepe303 said:
Don't you get tired of saying the same crap ?
You suck at making projectors. Move on and find another hobby.
My projector has a 15.4" Wuxga, Pro reflector, Pro lens. Is it brighter than a high dollar commercial projector ? NO !
But the picture is 10x better, the resolution is better than HD, and I BUILT IT MYSELF !!!
Move on man, move on.
hailrazer said:
Might be that I "suck", but it's not an argument against the fact, that any DIY projector "sucks" compared to a commercial one. Not even a "high dollar" one, also "low dollar" one wins definitely, in terms of brightness (man, you certainly don't realize how much it wins), sharpness, picture quality, and general feasibility. There is only lamp issue, which in fact is no longer an issue, as modern commercial projectors use lamps rated for 3k hours, or even 6k hours.
Good for you that you built it yourself, and you are happy, but let me be realistic. And don't fool other people, as they may spent lots of money and time just to realize it was a serious mistake. How much did you spend on parts? Like 1200$, or even more? Oh man, just check what you can have for 1200$ out of the box, 2 year warranty, nice, small, bright, quiet and convenient unit. I know it's a DIY forum, that's why I'm here, but even DIY ideas should be based on reasonable conditions. Would you build a TV-set? Perharps you would say it's crazy, as you can't build anything even close in quality to an old TV-set from a thrift store. Why don't you build a vacuum cleaner? Or a refrigerator? Unfortunately, the same applies to projectors nowadays, with some exceptions, like you might get some parts for free (broken LCD, that can be used, lens from an old OHP, and so on).
So, how is your projector 10x better, what do you mean, brightness, contrast ratio, noise, power consumption, size, convenience of use? Do you have zoom, efficient keystone correction, that does not spoil focus, may be you even have lens shift feature, as commercial projectors in 1000$+ range usualy have this? No, you only have high res panel, which does not translate to a significant image improvement, as TV and DVD are low resolution sources, and your cheap fresnel lens spoil any potential benefits of a high-res panel. It would be fine if you could build it for 300$, assuming you will not break anything in the process (like and LCD, and have to buy a new one, it happens!)
Regards
actually iv spent $120 ... and im happy ... the point to this thing is to get something decent for cheap ... its just a bonus that it happens to be that my $120 ... looks just as good as most $800 projectors that iv seen. and if youre not into this project anymore
i really think you should leave if youre not gunna contribute
i really think you should leave if youre not gunna contribute
v1d9uy said:
You would contribute to the subject if you could explain how to improve brightness, or explain why we can't improve it significantly. I can do both, and as you can see I did a bit in my first post in this thread. Now, what did you contribute?
Regards
did you even read this thread ?? ... please read before you comment i said better reflector bigger nicer lens ... thats perty easy...
Sorry, I confused you with the other guy, who was only "enthusiastic", but did not contribute anything.
Regards
Regards
granted the bigger lens will cost $75 up .. and the reflector varies but if i can keep mine under $200 ill be very happy with whatever my results
You're quite pathetic Pepe.
maybe oneday you will get to see a High Quailty Diy Projector and then you will know.
But here is a FACT. You built ONE and weren't happy with it. IN NO WAY DOES THIS MAKE YOU AN EXPERT ON DIY PROJECTORS !!
I have compared mine to $1200-2000 projectors and mine BLOWS them away. They do get brighter, but they lose contrast and color brilliance because of that.
Go back to your commercial projector and be happy with it's low resolution and washed out colors. And stop trying to persuade people you know what you're talking about when you obviously don't.
maybe oneday you will get to see a High Quailty Diy Projector and then you will know.
But here is a FACT. You built ONE and weren't happy with it. IN NO WAY DOES THIS MAKE YOU AN EXPERT ON DIY PROJECTORS !!
I have compared mine to $1200-2000 projectors and mine BLOWS them away. They do get brighter, but they lose contrast and color brilliance because of that.
Go back to your commercial projector and be happy with it's low resolution and washed out colors. And stop trying to persuade people you know what you're talking about when you obviously don't.
Pepe, is that you? Heck, I thought by now you would be tired of dissing everyone's work.
Actually, one of the members of LL measured about 430 lumens in his setup using the pro reflector, removed antiglare, etc. Yeah, and he did it right also. This measurment was higher than the real world measurements of a lot of commercial projectors that continually claim thousands of lumens, but generally deliver about 300-400 during home theater use.
Why do you come on here? Are you that bitter over your failure that you must justify it by waiting in the wings, just so you can pounce on some guy who asks for help with his setup?
Look, just taking a cue from your quote, if the lamp life of commercial projectors is getting cheaper and lasting longer then that only means that we have more options for increasing our brightness. You know, there's no law that says we cannot also use a commercial projector bulbs if we find it economically advantageous. The fact that we don't use them means that we do not find it economically advantageous to use them, thereby negating your claim that there is no longer a cost issue associated with using them.
I would sugest the following steps:
1) Go with a spherical reflector. If the LL reflector will fit your bulb then spend the money and get it. It's well worth it.
2) Reduce your screen size until the brightness is acceptable for you. Generally, if you watch your projector with ambient lighting then you should keep your screen size below 72 inches diagonal (4:3 aspect ratio)
3) Put a black border on your screen, preferably with the screen recessed inside the border. This will reduce reflections hitting the screen and decreasing your contrast.
4) Move your room lights around so that none of them shines directly on the screen.
5) Get a bright white screen such as Parkland plastic polywall (~$12 for 4X8 at hardware store)
6) Try adjusting your lamp closer to the rear fresnal. Many of us have found that our lamps are significantly brighter if we move them about an inch or so closer to the rear fresnal than the focal length of the rear fresnal.
7) You can try a condenser setup. I haven't tried them yet, but I hear they improve brightness about 30%. However, the 400 watt bulb may be a little too hot for them.
8) Antiglare removal should increase brightness about 20-50%, but it is risky. You could destroy your panel.
9) Finally, you may want to consider a more expensive bulb with a shorter arclength. Ushio has a 575W and a 250watt bulb with arclengths of 7 and 5mm, repsectively. These last about 3000 hours and cost between $120-$180. this particular solution would not work for me because my family watches my projector all day long. We simply put too much mileage on our bulb. But if you only use yours for watching a movie here and there, then it may be worth it.
These should help tremendousely.
If you really look objectively at the subject, you ´ll have to admit that there is no way that a DIY projector can beat a commercial unit.
It´s not the lack of intelligence or craftsmanship, but the lack of facilities and possibilities we all have.
With the falling prices of commercial projectors there is hardly any advantage for DIY.
Even the higher resolution of most LCD panels can´t be count as new technologies like DLP, make it hard to see any pixel structure, even at lower resolution.
So unless you get many parts for free, or you really have fun in building stuff. Don´t do it.
It´s great fun and all, and it always amazes me what people can accomplish, but don´t try to fool anybody into thinking that he will get even near the quality of a high class commercial unit.
It´s not the lack of intelligence or craftsmanship, but the lack of facilities and possibilities we all have.
With the falling prices of commercial projectors there is hardly any advantage for DIY.
Even the higher resolution of most LCD panels can´t be count as new technologies like DLP, make it hard to see any pixel structure, even at lower resolution.
So unless you get many parts for free, or you really have fun in building stuff. Don´t do it.
It´s great fun and all, and it always amazes me what people can accomplish, but don´t try to fool anybody into thinking that he will get even near the quality of a high class commercial unit.
well if yer smart .... you can make a nice pj for under $300 ...
now you go find a commercial one that has better specs than a DIY for $300 hell even $600 then add the crazy price of there commercial bulb and there still low hours and the DIY pj still wins by a long shot ... but thats just me likeing to save money......and likeing the better specs
now you go find a commercial one that has better specs than a DIY for $300 hell even $600 then add the crazy price of there commercial bulb and there still low hours and the DIY pj still wins by a long shot ... but thats just me likeing to save money......and likeing the better specs
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