Re: to the dude above
A agree with you. Im kind of tired of seeing everyone use an OHP and an lcd pannel. In my opinion, that is no way to go if you want to make an lcd projector. There are so many other ways to go, and people still flock to the ohp setup. Why? I guess it is easy, but what is the fun in that? Mabey we should start a thread, "new ideas and concepts."
prjctr_builder said:the previous post sounded to me like it was written about 2 years ago, when we knew nothing about projection....
my point is... though we did have some progress with learning a thing or two about projection, and some people even had pretty good results, most of us never applied new concepts to their projects. Many people told us which way not to go, but still everyone keeps trying their luck. to me, this forum seems like a closed circle that has no beginning, and seemingly no end as well.
A agree with you. Im kind of tired of seeing everyone use an OHP and an lcd pannel. In my opinion, that is no way to go if you want to make an lcd projector. There are so many other ways to go, and people still flock to the ohp setup. Why? I guess it is easy, but what is the fun in that? Mabey we should start a thread, "new ideas and concepts."
rbraithwaite said:
No offence, but you really need to look up the meanings of volts, amps etc. The whole idea of a dimmer switch is to limit or in your words "affect" the voltage to the light. So (unless your light will; not work on lower voltage which it probably will) there is nothing wrong with a dimmer switch.
Does anyone know if it's safe to put a dimmer switch between the mains cable and the ballast of a 400w MH lamp. Just wondered if I did this that I might affect the volts, amps, etc. going to the lamp?
Thanks in advance, Richard
A dimmer would not be effective at all.
Metal halides operate with constant voltage between an arc gap
filled with gas.
Going below the rated voltage will end up turning the bulb off.
All other lamps that produce light using filaments will be able to use a dimmer eg. Incandescent and halogens.
L8r
Thanks in advance, Richard
A dimmer would not be effective at all.
Metal halides operate with constant voltage between an arc gap
filled with gas.
Going below the rated voltage will end up turning the bulb off.
All other lamps that produce light using filaments will be able to use a dimmer eg. Incandescent and halogens.
L8r
From Redevil
A dimmer would not be effective at all.
Metal halides operate with constant voltage between an arc gap
filled with gas.
Going below the rated voltage will end up turning the bulb off.
Redevil is correct.
The ballast lamp fault condition sensor will turn the power off. It is possible to use a dimmer with a Metal Halide arc lamp and is done by people with aquariums to simulate various daylight conditions as in nature, but it is not a simple matter.
Search for aquarium lighting.
A dimmer would not be effective at all.
Metal halides operate with constant voltage between an arc gap
filled with gas.
Going below the rated voltage will end up turning the bulb off.
Redevil is correct.
The ballast lamp fault condition sensor will turn the power off. It is possible to use a dimmer with a Metal Halide arc lamp and is done by people with aquariums to simulate various daylight conditions as in nature, but it is not a simple matter.
Search for aquarium lighting.
Re: to the dude above
If you think this is old, i didn't manage to explain exactly what i meant.
I am NOT using a regular tft panel for ohps which you can buy at ebay. It is a TFT MONITOR for PCs, that's the difference (better picture, response time <30ms and you can buy it everywhere). The fact is, if there aren't panels in a 2" format with 1024x768(or at least 800x600) pixels payable for us (about 3000$ plus controllers all in all over 4000$) we need a fresnel lense (the best and cheapest are from damaged ohps), otherwise you are not able to spread the light through such a big screen (over 10"). And in my opinion a MH bulb is not needed because the installation costs and the price for one bulb(40$) are too high. My bulb only costs 4.99$... The NEW thing on it is the cooling of the lamp. Because i can use a 500W bulb without a fan which makes noise like an airplane and the panel is not damaged because there comes absolutely no heat to the panel... The second thing is; it is really hard to build an optic for the projection. and all the guys in here telling they are using a fresnel lens for the projected image itself are lying, because it is not possible. Physic tells you will never have a sharp picture with only one lense, you need at least 2; and real good pictures are only available with three lens optics. ()-)(-!) <---- image of a 3lens optic like in ohps [convex-concave-plan convex] and why not using the one of your damaged ohp.....
So i think my way is a new concept because no one ever showed a finished result of his projector with a PC TFT Monitor and a REALLY cheap bulb, and i will in about one week...
By the way prjetr_builder do you have a new concept??? or are you still using your ohp setup??
prjctr_builder said:the previous post sounded to me like it was written about 2 years ago, when we knew nothing about projection....
my point is... though we did have some progress with learning a thing or two about projection, and some people even had pretty good results, most of us never applied new concepts to their projects. Many people told us which way not to go, but still everyone keeps trying their luck. to me, this forum seems like a closed circle that has no beginning, and seemingly no end as well.
If you think this is old, i didn't manage to explain exactly what i meant.
I am NOT using a regular tft panel for ohps which you can buy at ebay. It is a TFT MONITOR for PCs, that's the difference (better picture, response time <30ms and you can buy it everywhere). The fact is, if there aren't panels in a 2" format with 1024x768(or at least 800x600) pixels payable for us (about 3000$ plus controllers all in all over 4000$) we need a fresnel lense (the best and cheapest are from damaged ohps), otherwise you are not able to spread the light through such a big screen (over 10"). And in my opinion a MH bulb is not needed because the installation costs and the price for one bulb(40$) are too high. My bulb only costs 4.99$... The NEW thing on it is the cooling of the lamp. Because i can use a 500W bulb without a fan which makes noise like an airplane and the panel is not damaged because there comes absolutely no heat to the panel... The second thing is; it is really hard to build an optic for the projection. and all the guys in here telling they are using a fresnel lens for the projected image itself are lying, because it is not possible. Physic tells you will never have a sharp picture with only one lense, you need at least 2; and real good pictures are only available with three lens optics. ()-)(-!) <---- image of a 3lens optic like in ohps [convex-concave-plan convex] and why not using the one of your damaged ohp.....
So i think my way is a new concept because no one ever showed a finished result of his projector with a PC TFT Monitor and a REALLY cheap bulb, and i will in about one week...
By the way prjetr_builder do you have a new concept??? or are you still using your ohp setup??
Slize
Please refrain from using the word lying. You can still make your point by better choice of words not so abrasive.
For example you could say "People using a single lens may experience slight bluring of the colours which can be improved by using two or more lens.
I have a 3M 1705 OHP which uses a single lens and I have examined the image carefully and can find no objectionable colour blurring at all. And every part is well focussed.
Technically you are correct. Practically is a different matter.
Please refrain from using the word lying. You can still make your point by better choice of words not so abrasive.
For example you could say "People using a single lens may experience slight bluring of the colours which can be improved by using two or more lens.
I have a 3M 1705 OHP which uses a single lens and I have examined the image carefully and can find no objectionable colour blurring at all. And every part is well focussed.
Technically you are correct. Practically is a different matter.
yap you're right. i apologize if it sounds agressive but my english is very bad. I did not mean lying, i just meant they do not say the truth ;-)
The first point is: I said single lens, but what i meant was fresnel lens. It is not possible to have a 99% sharp picture with a single lens (except those from ohps). Your single lens is also possible because it is from a ohp just like mine... and pictr_builder says ohp is no good idea.
The second point is: it is important to have a perfect combination of the focuses of the fresenel lens and the optic for the image projection. In your case it fits, because you use an ohp. But others who try to combine two different types of lenses won't get a good result; at least i didn't see any in this forum yet. And two fresnel lenses (one for light spreading one for projection) won't work at all... that's a fact
slize idea bad....maybe not.......also 5500k light filter VERY NICE bottom of post
I am new to posting to this forum but am not new to reading the forum. I've been around for a about 6months reading everyones post. Only reason I have not put my 2cents in is because I did not have a complete working lcd projector and didnt think it would be wise to post ideas on somthing i dont even have.
I will agree that using a 500watt halogen bulb might not be up to par......but whats wrong with using a 15inch lcd panel for a computer. The only bad thing I can see about going this route is the project case will be much bigger and you will also have to have a computer to use the monitor. It seems to me that most people on this forum are talking about SIZE....everyones talking about making thier projector smaller...using smaller lcd's. I dont have a problem with smaller size either.....i think a small lcd projector would be very practical. Slize on the other hand is going for quality, minus the 500watt halogen, and you guys are knockin him for it, saying that his post seems 2years old.....I've looked all over the post and have yet to find someone acctually saying they used a 15inch lcd monitor. Just post from people saying they know a guy/heard of a guy that used a ViewSonic VG 150. I think Slize idea is a great one if you want a big picture with nice quality....lets face it once you go past 40inches on the 5inch lcd the image gets pretty crapy. From what im reading unless you have $4000 to buy a 1inch super lcd on crack there is no way you are going to go bigger then 40inches with a 5inch lcd with nice quality. Saying that I hope that some of people that have been here in this forum from the begining of time will comment on why they think using a 15inch lcd is bad/good
I've also found a solution for converting the Kelvin of your lightsource to 5500k. Its a gel thats used in filming studios to put over halogen lights....but works the same on metal halides. It can be found here for 6.95 for a 20"x 24" its called Roscolux Tungsten Conversion Filters get the Full Blue. http://64.213.162.194/catalog/ws2001/gel-filters-theater.html
I use mine on a 400watt metalhalide with 4100k Why convert a 400watt metalhalide you ask. The main reason being that 5500k-6000k is ideal for projecting. The other is because as many of you know the metal halide is greatly known for for its fluctuation of Kelvin threw hours of use, by using this filter you have a constant output of 5500k. AND YES some lumens are lost in the process of going threw the filter. I asked that guy at Full compass how much light is lost on average threw the filter and he says no more the 5-10% but if you look at the data for a while i think you'll find just as I have that the pro's outway the con's. I hope my first 2cents has helped the DIYLCD comunity look forward to replies....both good and bad.
I am new to posting to this forum but am not new to reading the forum. I've been around for a about 6months reading everyones post. Only reason I have not put my 2cents in is because I did not have a complete working lcd projector and didnt think it would be wise to post ideas on somthing i dont even have.
I will agree that using a 500watt halogen bulb might not be up to par......but whats wrong with using a 15inch lcd panel for a computer. The only bad thing I can see about going this route is the project case will be much bigger and you will also have to have a computer to use the monitor. It seems to me that most people on this forum are talking about SIZE....everyones talking about making thier projector smaller...using smaller lcd's. I dont have a problem with smaller size either.....i think a small lcd projector would be very practical. Slize on the other hand is going for quality, minus the 500watt halogen, and you guys are knockin him for it, saying that his post seems 2years old.....I've looked all over the post and have yet to find someone acctually saying they used a 15inch lcd monitor. Just post from people saying they know a guy/heard of a guy that used a ViewSonic VG 150. I think Slize idea is a great one if you want a big picture with nice quality....lets face it once you go past 40inches on the 5inch lcd the image gets pretty crapy. From what im reading unless you have $4000 to buy a 1inch super lcd on crack there is no way you are going to go bigger then 40inches with a 5inch lcd with nice quality. Saying that I hope that some of people that have been here in this forum from the begining of time will comment on why they think using a 15inch lcd is bad/good
I've also found a solution for converting the Kelvin of your lightsource to 5500k. Its a gel thats used in filming studios to put over halogen lights....but works the same on metal halides. It can be found here for 6.95 for a 20"x 24" its called Roscolux Tungsten Conversion Filters get the Full Blue. http://64.213.162.194/catalog/ws2001/gel-filters-theater.html
I use mine on a 400watt metalhalide with 4100k Why convert a 400watt metalhalide you ask. The main reason being that 5500k-6000k is ideal for projecting. The other is because as many of you know the metal halide is greatly known for for its fluctuation of Kelvin threw hours of use, by using this filter you have a constant output of 5500k. AND YES some lumens are lost in the process of going threw the filter. I asked that guy at Full compass how much light is lost on average threw the filter and he says no more the 5-10% but if you look at the data for a while i think you'll find just as I have that the pro's outway the con's. I hope my first 2cents has helped the DIYLCD comunity look forward to replies....both good and bad.
Mystique
Good job on the filter research.
I need a boost from 4100K to 5500K.
I did not see it there or I may be blind.
5500K would be ideal, and cheap.
Would produce a much better picture as far as color.
As for the 15" LCD, to hard to find converter board for some.
And to hard to find a cheap fresenel that would cover it.
But if you use a overhead projector that has a lare staging area,
that would be the way.
Nothing wrong with the 15" LCD if you can find the stuff for it.
And if you do, then you got yourself a HDTV projector.
My OHP LCD can handle 1024X768.
My PC games look excellent.
TV image at 640X480 (looks good at 95" Diag)
Good luck, good job
Keep me posted about the filter
Later
Good job on the filter research.
I need a boost from 4100K to 5500K.
I did not see it there or I may be blind.
5500K would be ideal, and cheap.
Would produce a much better picture as far as color.
As for the 15" LCD, to hard to find converter board for some.
And to hard to find a cheap fresenel that would cover it.
But if you use a overhead projector that has a lare staging area,
that would be the way.
Nothing wrong with the 15" LCD if you can find the stuff for it.
And if you do, then you got yourself a HDTV projector.
My OHP LCD can handle 1024X768.
My PC games look excellent.
TV image at 640X480 (looks good at 95" Diag)
Good luck, good job
Keep me posted about the filter
Later
Hello all,
Long time no see.
I havent gotten much actual progress done in a while. Things have ground to a standstill as school consumes my pathetic life. Quite irritating really.
Does anyone know a place where I can get weird and exotic ribbon cables? I've got a couple LCD's (mostly VG150's) with ripped ribbon cables that I'd like to use again. I just need to find someplace to get these weirdo ribbon cables (with strange end connectors.... photo "soon"). I'm still crying, but for now I'm just glad that the replaceable ribbon cable broke, and not the one coming off the lcd.
Sadly the best plan I've thought of for the future is casting my own ellipsoidal reflectors. Electroforming has proved too hard to setup as a hobbiest operation, and doesnt let me do fun things like add waterblocks to the reflector. So I'm starting my own little foundry, in my backyard. After I get a couple of these things cast, I'm going to have to figure out some way to get vacuum deposition hot or cold mirroring (cant remember which.... the one that lets heat go through, but bounces light).
With that and some decent waterflow, I should be ready for 400 watts of <i>completely and totally silent</i> sweet metal halide loving. goodbye fans!
if all goes well, I'll make a HUGE ******* reflector for the 1000 watt metal halides I've got lying around. these bulbs are ******** gigantic. over a foot long, seven inches in diameter. i'll probably end up having to make the damned reflector alone about three feet long just to fit the damned bulbs in. in the end, it'll be something vaguely taller than your industrial sized mini-fridge, but should give imax a run for the money. 150,000 lumens. what the hell do you do with that much light? honestly? since it going to have to be a insultingly long reflector, it'll get 93% - 95% optical efficiency. thats a recoculous amount of light. great scot.
then i "just" need to scrounge up a couple grand for the bigass 24 inch LCD to go with it. i wish multiple display technology were further up to par, i'd much rather just have a two by three array of 400watt 1280x1024's, for the same price, but the righteous computing hacks required to actually do anything besides basic computing (ie videos, video games, movies, et all) are.... well beyond my realm of knowledge, and i suspect far beyond the abilities of modern desktop computing.
Most of all, I need to get off my *** and move. I havent dont jack or **** really since the last time i posted here, aside from assembling a couple projectors for myself and friends. I've got the molding sand, although I'm thinking of switching to some sort of plaster/cermaic casting, for longevity issues. its time to move on though.
Myren
Long time no see.
I havent gotten much actual progress done in a while. Things have ground to a standstill as school consumes my pathetic life. Quite irritating really.
Does anyone know a place where I can get weird and exotic ribbon cables? I've got a couple LCD's (mostly VG150's) with ripped ribbon cables that I'd like to use again. I just need to find someplace to get these weirdo ribbon cables (with strange end connectors.... photo "soon"). I'm still crying, but for now I'm just glad that the replaceable ribbon cable broke, and not the one coming off the lcd.
Sadly the best plan I've thought of for the future is casting my own ellipsoidal reflectors. Electroforming has proved too hard to setup as a hobbiest operation, and doesnt let me do fun things like add waterblocks to the reflector. So I'm starting my own little foundry, in my backyard. After I get a couple of these things cast, I'm going to have to figure out some way to get vacuum deposition hot or cold mirroring (cant remember which.... the one that lets heat go through, but bounces light).
With that and some decent waterflow, I should be ready for 400 watts of <i>completely and totally silent</i> sweet metal halide loving. goodbye fans!
if all goes well, I'll make a HUGE ******* reflector for the 1000 watt metal halides I've got lying around. these bulbs are ******** gigantic. over a foot long, seven inches in diameter. i'll probably end up having to make the damned reflector alone about three feet long just to fit the damned bulbs in. in the end, it'll be something vaguely taller than your industrial sized mini-fridge, but should give imax a run for the money. 150,000 lumens. what the hell do you do with that much light? honestly? since it going to have to be a insultingly long reflector, it'll get 93% - 95% optical efficiency. thats a recoculous amount of light. great scot.
then i "just" need to scrounge up a couple grand for the bigass 24 inch LCD to go with it. i wish multiple display technology were further up to par, i'd much rather just have a two by three array of 400watt 1280x1024's, for the same price, but the righteous computing hacks required to actually do anything besides basic computing (ie videos, video games, movies, et all) are.... well beyond my realm of knowledge, and i suspect far beyond the abilities of modern desktop computing.
Most of all, I need to get off my *** and move. I havent dont jack or **** really since the last time i posted here, aside from assembling a couple projectors for myself and friends. I've got the molding sand, although I'm thinking of switching to some sort of plaster/cermaic casting, for longevity issues. its time to move on though.
Myren
Wow... I'm a newbie first off, but I am a quick study. I've been browsing this forum for the past few months dreaming of making myself a projector (Some of the people here at work think I'm crazy) anyway, I've never been a part of a forum/newsgroup before, but I HAVE done lots of DIY projects. I would just like to know if there's anything special I should know about before I start making a PJ...
Any help would be greatly appreciated.
P.S. I am a purist when it comes to DIY. I'm not interested in making an OHP/LCD combo. I want to make a box with a big honkin' light and do it in the $500 price range. I hope to become an important part of your community.
Any help would be greatly appreciated.
P.S. I am a purist when it comes to DIY. I'm not interested in making an OHP/LCD combo. I want to make a box with a big honkin' light and do it in the $500 price range. I hope to become an important part of your community.
Redevil
Hi: I've been in the forum for a little while and have read extensively on your setup. It's very much like the one I am building, although I'm going with the (too many dollars ~L~) laptop screen and controller card.
My card is on the way from Taiwan, and the panel is coming from the US...waiting for parts is the story of my life. I'd like you to take a look at a PCX I found and get your opinion on the lens. It's a 7-1/2” DIAM BY 20” FL PCX LENS - New This Week!
Item No.: L2152 from surplus shed. I'd also appreciate your advice on what lens to buy for next to my 400 MH lamp.
I was one of the missinformed folks that thought an old CRT lens would be helpfull to this project (untill I spent most of last night reading back posts that is). Fortuneately I didnt pay anything for the JBL PJ it was a DOA on it's way to the dump when I grabbed it (hehe also got a working Novabeam 1A from the guy).
Any assistance in my new nightmare....... "optics" would be great.
zardoz
Hi: I've been in the forum for a little while and have read extensively on your setup. It's very much like the one I am building, although I'm going with the (too many dollars ~L~) laptop screen and controller card.
My card is on the way from Taiwan, and the panel is coming from the US...waiting for parts is the story of my life. I'd like you to take a look at a PCX I found and get your opinion on the lens. It's a 7-1/2” DIAM BY 20” FL PCX LENS - New This Week!
Item No.: L2152 from surplus shed. I'd also appreciate your advice on what lens to buy for next to my 400 MH lamp.
I was one of the missinformed folks that thought an old CRT lens would be helpfull to this project (untill I spent most of last night reading back posts that is). Fortuneately I didnt pay anything for the JBL PJ it was a DOA on it's way to the dump when I grabbed it (hehe also got a working Novabeam 1A from the guy).
Any assistance in my new nightmare....... "optics" would be great.
zardoz
zardoz
At that price, worth a shot.
Get two of them.
Well worth project.
A bar owner that I know spent $7,000.00 for his projector.
It has two bulbs. Cost him $750.00 for each bulb for him to get back up.
My cost for bulb replacement $26.00.
I have all kind of people coming over to look at it.
They say its great.
My friend bought a 53 inch rear projection TV.
And is bringing or gona tell them to come and get it back because
the picture is not that great for the price he paid.
Good Luck
By the way, the optics must, I mean must be perfectly aligned.
L8r
At that price, worth a shot.
Get two of them.
Well worth project.
A bar owner that I know spent $7,000.00 for his projector.
It has two bulbs. Cost him $750.00 for each bulb for him to get back up.
My cost for bulb replacement $26.00.
I have all kind of people coming over to look at it.
They say its great.
My friend bought a 53 inch rear projection TV.
And is bringing or gona tell them to come and get it back because
the picture is not that great for the price he paid.
Good Luck
By the way, the optics must, I mean must be perfectly aligned.
L8r
Attachments
Redevil
If I recall you are running a 14 inch screen? and are getting great result with your 6 inch/14fl PCX. Do you know if the 7.5 inch/20fl is going to make my PJ a "longer or shorter" overall box (dimensionally speaking) I can handle the 10 feet to the screen distance now.. but in the near future intend to move it into a spot where I can get about 18 or 20 feet from the screen. Screen to be determined, currently I'm watching the Novabeam CRT on a bed sheet LOL. But in the new location I am thinking of really testing myself and building a Torus screen... If my new hobby doesnt kill me the wife will for sure!
zardoz
If I recall you are running a 14 inch screen? and are getting great result with your 6 inch/14fl PCX. Do you know if the 7.5 inch/20fl is going to make my PJ a "longer or shorter" overall box (dimensionally speaking) I can handle the 10 feet to the screen distance now.. but in the near future intend to move it into a spot where I can get about 18 or 20 feet from the screen. Screen to be determined, currently I'm watching the Novabeam CRT on a bed sheet LOL. But in the new location I am thinking of really testing myself and building a Torus screen... If my new hobby doesnt kill me the wife will for sure!
zardoz
Zardoz
My LCD is 10" Diag.
Yes this lens will make your PJ box longer.
As far as the picture size, I would not know.
For me it was a try it till I get it right (one year later).
I will tell you one thing, a 4 1/2" PCX lens with FL of 20" at ten feet produced an image of about 1/2 the size.
Therefore this is maybe what you may be looking for in the future to get that 18 or 20 feet.
If I where you I would get the 7 1/2 for the bulb side for sure, another for the objective and a 4 1/2 as an extra to see which one would work for you.
The diagram that I have shown is a basic configuration.
When you get to that point make a post on this site and I will
tell you a couple of other things that will fine tune your image.
L8r
My LCD is 10" Diag.
Yes this lens will make your PJ box longer.
As far as the picture size, I would not know.
For me it was a try it till I get it right (one year later).
I will tell you one thing, a 4 1/2" PCX lens with FL of 20" at ten feet produced an image of about 1/2 the size.
Therefore this is maybe what you may be looking for in the future to get that 18 or 20 feet.
If I where you I would get the 7 1/2 for the bulb side for sure, another for the objective and a 4 1/2 as an extra to see which one would work for you.
The diagram that I have shown is a basic configuration.
When you get to that point make a post on this site and I will
tell you a couple of other things that will fine tune your image.
L8r
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