Hey my fellow Diy-ers and No0bs these are my email conversations with Allan Stapples from... http://people.eecs.ku.edu/~astaples/projector/index.htm these have helped me i hope it will help you. OR ELSE I GUARANTEE MONEY BACK!!! 
REFLECTOR ISSUE
Jimmy,
In this type of setup, reflectors only work that are equal to or smaller than the diameter of the projection lens you are using. There are some tricks you can do though, but I haven't experimented with them enough to be able to say for sure what you should do. I would go ahead and use the reflector because you will see a little light gain with it, but not as much as you should theorectically experience.
Also, as long as you use a piece of glass in the fresnel mount, you should be fine with heat. The heat from these lamps isn't enough to damage components as long as you use appropriate cooling such as what I describe on the website. The glass is needed to keep the fresnel from warping (heat makes fresnel lenses want to bend away from the heat source for some reason).
Please let me know if there is anything else I can do to help you.
Regards,
Alan, DIY Labs
http://www.diylabs.org/
LCD's...
Hello,
If the actual screen size is near 4.3", then you can probably get away with using the Delta20 which will make a huge picture on the wall even from about 6 feet away. Overhead projectors do make huge images on the wall, but not when the source is only 5". The lens triplet that I offer is basically a very fancy overhead projector lens - it has the same focal properties, but is much sharper and has color correction technology built in. The reason Zark has such terrible color depth is because his camera won't take good pictures in the dark - that picture is actually REALLY dim in reality and the camera is doing everything it can to try and capture the image. I've built his projector before and the compact florecents are actually a bit pink/yellow in color once you use a lens system to focus them. I was really suprized because they look so white. I would definately recommend going to an overhead projection panel and a high quality lens (whether it be mine or others) if you really want to get good quality. Another thing is that those auto LCD panels don't typically show that many colors - they rely on your eye to blend colors together from afar, but when the picture is blown up to 80" across, your eye will be very displeased with the coloration, I think. The pixels end up being the size of Canadian dimes in most cases. I always hate telling people that the way to get a good projector is to spend more money, but in your case I think that would be the best.
Regardless of what you decide, I'd definately go with a metal halide light kit as opposed to any other way of lighting. It's VERY cheap to run (about a penny an hour) and the bulbs last for about 15,000 to 20,000 hours. Also, you'll get the whitest and truest color out of it. I'm in the process of posting new results pictures on the web because I've not got my projector to be even brighter just using the 400watt metal halide. You can check out the results page now, but realize that the pictures are now outdated (although still pretty good considering there's a lot of light pouring through my windows). Here is the link http://people.eecs.ku.edu/~astaples/projector/results.htm
Let me know if I can help you out any more. I'm interested to hear what you decide. Also, I'd love pictures of your project as you go along if you are able to take them.
Regards,
Alan, DIY Labs
http://www.diylabs.org/
I ASKED WHAT KIND OF LCD WAS HE USING-
Hello,
I am not using a 4" LCD panel in that picture, but you can get the
same
results using one. If you are using a 5" panel, and if you have enough
distange between the projector and the screen, then I would recommend
using
the lens triplet. I would say that you'd probably want about 8-10 feet
between the projector and the wall when using a 5" LCD to get roughly a
40
screen on the wall. Is your panel exactly 5" or is it 5.6? If you tell
me
exactly how far away from the wall you are and how large your panel is,
then
I can tell you exactly how large the screen size will be on the wall.
Also
feel free to let me know if you have any other questions.
Regards,
Alan, DIY Labs
http://www.diylabs.org/
REFLECTOR ISSUE
Jimmy,
In this type of setup, reflectors only work that are equal to or smaller than the diameter of the projection lens you are using. There are some tricks you can do though, but I haven't experimented with them enough to be able to say for sure what you should do. I would go ahead and use the reflector because you will see a little light gain with it, but not as much as you should theorectically experience.
Also, as long as you use a piece of glass in the fresnel mount, you should be fine with heat. The heat from these lamps isn't enough to damage components as long as you use appropriate cooling such as what I describe on the website. The glass is needed to keep the fresnel from warping (heat makes fresnel lenses want to bend away from the heat source for some reason).
Please let me know if there is anything else I can do to help you.
Regards,
Alan, DIY Labs
http://www.diylabs.org/
LCD's...
Hello,
If the actual screen size is near 4.3", then you can probably get away with using the Delta20 which will make a huge picture on the wall even from about 6 feet away. Overhead projectors do make huge images on the wall, but not when the source is only 5". The lens triplet that I offer is basically a very fancy overhead projector lens - it has the same focal properties, but is much sharper and has color correction technology built in. The reason Zark has such terrible color depth is because his camera won't take good pictures in the dark - that picture is actually REALLY dim in reality and the camera is doing everything it can to try and capture the image. I've built his projector before and the compact florecents are actually a bit pink/yellow in color once you use a lens system to focus them. I was really suprized because they look so white. I would definately recommend going to an overhead projection panel and a high quality lens (whether it be mine or others) if you really want to get good quality. Another thing is that those auto LCD panels don't typically show that many colors - they rely on your eye to blend colors together from afar, but when the picture is blown up to 80" across, your eye will be very displeased with the coloration, I think. The pixels end up being the size of Canadian dimes in most cases. I always hate telling people that the way to get a good projector is to spend more money, but in your case I think that would be the best.
Regardless of what you decide, I'd definately go with a metal halide light kit as opposed to any other way of lighting. It's VERY cheap to run (about a penny an hour) and the bulbs last for about 15,000 to 20,000 hours. Also, you'll get the whitest and truest color out of it. I'm in the process of posting new results pictures on the web because I've not got my projector to be even brighter just using the 400watt metal halide. You can check out the results page now, but realize that the pictures are now outdated (although still pretty good considering there's a lot of light pouring through my windows). Here is the link http://people.eecs.ku.edu/~astaples/projector/results.htm
Let me know if I can help you out any more. I'm interested to hear what you decide. Also, I'd love pictures of your project as you go along if you are able to take them.
Regards,
Alan, DIY Labs
http://www.diylabs.org/
I ASKED WHAT KIND OF LCD WAS HE USING-
Hello,
I am not using a 4" LCD panel in that picture, but you can get the
same
results using one. If you are using a 5" panel, and if you have enough
distange between the projector and the screen, then I would recommend
using
the lens triplet. I would say that you'd probably want about 8-10 feet
between the projector and the wall when using a 5" LCD to get roughly a
40
screen on the wall. Is your panel exactly 5" or is it 5.6? If you tell
me
exactly how far away from the wall you are and how large your panel is,
then
I can tell you exactly how large the screen size will be on the wall.
Also
feel free to let me know if you have any other questions.
Regards,
Alan, DIY Labs
http://www.diylabs.org/
Allan on Artographs...
This was during my "artograph" craze..lol im done wiht artographs now...who knows if it would of worked...
He doesnt know...
Jimmy,
I'm not sure what an Artograph is, but if you could send me a picture or better describe it to me, I would be happy to help out. Judging by what you have told me, you would at least need some sort of lens to focus the reflected image onto the wall.
Regards,
Alan, DIY Labs
http://people.eecs.ku.edu/~astaples
I GAVE SOME INFO ON IT AND...
Jimmy,
Unfortunately I don't think that would work. There are basically two problems: heat and reflection. The heat of a 1000w+ bulb might be a bit too much for the top surface of an LCD panel, but the main difficulty is that nearly all color LCD panels use a backlight instead of a reflective foil. You could, in theory, remove the backlight and put a mirror in its place (which is what I think you meant earlier), but then you are loosing about 75% of your total light output. LCDs filter about 50% of the light that passes through them, so even if you had a perfect mirror, the LCD panel would be twice-filtering the light that passes through it. Thus, 50% of 50% is 25% . . . in other words, however bright your opaque projector is with a white sheet of paper, the LCD image would be 25% as bright for completely white image on the panel.
I hope that helps some. I know it was probably more discouraging than anything (that happens a lot with this project sometimes). If there is anything I can help you out with, please let me know. The one thing I can tell you that may be of interest is that the light bulb, reflector, and lens from your opaque projector would probably work well for a "Beta" version of a projector. The lamp life and color of light from an opaque projector are not typically well-suited for a video projector because the light is too yellow, and the lens is typically not as high of resolution as is preferred, but you could still use them for a preliminary version and then upgrade from there (that's what many people including myself have done). Again, feel free to let me know if I can help in any way.
Regards,
Alan, DIY Labs
http://people.eecs.ku.edu/~astaples/
This was during my "artograph" craze..lol im done wiht artographs now...who knows if it would of worked...
He doesnt know...
Jimmy,
I'm not sure what an Artograph is, but if you could send me a picture or better describe it to me, I would be happy to help out. Judging by what you have told me, you would at least need some sort of lens to focus the reflected image onto the wall.
Regards,
Alan, DIY Labs
http://people.eecs.ku.edu/~astaples
I GAVE SOME INFO ON IT AND...
Jimmy,
Unfortunately I don't think that would work. There are basically two problems: heat and reflection. The heat of a 1000w+ bulb might be a bit too much for the top surface of an LCD panel, but the main difficulty is that nearly all color LCD panels use a backlight instead of a reflective foil. You could, in theory, remove the backlight and put a mirror in its place (which is what I think you meant earlier), but then you are loosing about 75% of your total light output. LCDs filter about 50% of the light that passes through them, so even if you had a perfect mirror, the LCD panel would be twice-filtering the light that passes through it. Thus, 50% of 50% is 25% . . . in other words, however bright your opaque projector is with a white sheet of paper, the LCD image would be 25% as bright for completely white image on the panel.
I hope that helps some. I know it was probably more discouraging than anything (that happens a lot with this project sometimes). If there is anything I can help you out with, please let me know. The one thing I can tell you that may be of interest is that the light bulb, reflector, and lens from your opaque projector would probably work well for a "Beta" version of a projector. The lamp life and color of light from an opaque projector are not typically well-suited for a video projector because the light is too yellow, and the lens is typically not as high of resolution as is preferred, but you could still use them for a preliminary version and then upgrade from there (that's what many people including myself have done). Again, feel free to let me know if I can help in any way.
Regards,
Alan, DIY Labs
http://people.eecs.ku.edu/~astaples/
Allan on Retrofitting
I emailed Allan asking for his thoughts on Retrofitting and he...
Jimmy,
Usually it is difficult to retrofit an overhead projector with a new lamp because the light has to come from the same exact point that the old lamp emitted light from. Also, a 250watt metal halide probably isn't as bright as the overhead originally was with a halogen light. I believe that without a reflector, you really need to use a 400watt metal halide in order to make the upgrade worth while., Unfortuantely a 400w can't be fitted into an overhead projector, which is why I created my website to explain how to make what is effectively a high power overhead projector. A overhead projector is still good to have because it has the fresnel lens that you'll need for your video projector and you can also use the projection lens that comes with it. Let me know if there's anything else I can do to help you out.
Regards,
Alan, DIY Labs
TO BE CONTINUED.... 😉
I hope this was helpful.
😎 -JimmY-😎
I emailed Allan asking for his thoughts on Retrofitting and he...
Jimmy,
Usually it is difficult to retrofit an overhead projector with a new lamp because the light has to come from the same exact point that the old lamp emitted light from. Also, a 250watt metal halide probably isn't as bright as the overhead originally was with a halogen light. I believe that without a reflector, you really need to use a 400watt metal halide in order to make the upgrade worth while., Unfortuantely a 400w can't be fitted into an overhead projector, which is why I created my website to explain how to make what is effectively a high power overhead projector. A overhead projector is still good to have because it has the fresnel lens that you'll need for your video projector and you can also use the projection lens that comes with it. Let me know if there's anything else I can do to help you out.
Regards,
Alan, DIY Labs
TO BE CONTINUED.... 😉
I hope this was helpful.
😎 -JimmY-😎
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