HokieTT,
You might need to add a sheet of glass to your list to block the heat from your light. One sheet does ok. Two sheets and a gap between with fan does better. Measure temperature at fresnel location and see what you think If its up around 60 centigrade you are getting too hot
You might need to add a sheet of glass to your list to block the heat from your light. One sheet does ok. Two sheets and a gap between with fan does better. Measure temperature at fresnel location and see what you think If its up around 60 centigrade you are getting too hot
Jiggersplat,
as Richard already pointed out, you have two very critical parts in your design.
First, honeycomb, mmh, i don't see, why this honey comb is necessaire if you have a correct parallel beam from 1. reflector.
Second, half tranmissive mirrors may have 65:35 ratio, 65% light are transmitted, 35% are reflected.
Insofar, both, honeycomb and half transmissive mirror are mega light killers!
Third, the 2. reflector acts as an imaging system like a lens. A native projection objective isn't needed. Because it's in the image path, requirements for such a reflector are much higher than for only lighting purposes.
All in all, i don't believe that good results could be archieved.
Another option could be to cancel the half transmissive mirror completely and tilt the second imaging mirror to a moderate angle, so that the image can go out.
xblocker
as Richard already pointed out, you have two very critical parts in your design.
First, honeycomb, mmh, i don't see, why this honey comb is necessaire if you have a correct parallel beam from 1. reflector.
Second, half tranmissive mirrors may have 65:35 ratio, 65% light are transmitted, 35% are reflected.
Insofar, both, honeycomb and half transmissive mirror are mega light killers!
Third, the 2. reflector acts as an imaging system like a lens. A native projection objective isn't needed. Because it's in the image path, requirements for such a reflector are much higher than for only lighting purposes.
All in all, i don't believe that good results could be archieved.
Another option could be to cancel the half transmissive mirror completely and tilt the second imaging mirror to a moderate angle, so that the image can go out.
xblocker
Heat Limits
In an attempt to add a bit more science to the project, has anyone actually documented the temperatures produced by their projectors and projector bulbs? I'd like to see a comparison for relative heats for a range of setups. If you have ENX, FXL, Metal Hallide, whatever, what are the typical temps they produce, what cooling is needed, and if anybody knows, the temps when they just decide to blow!
I'm gonna pick up one of these guys from radio shack to measure temperature for our setup and post results.
Any info you gather, let me know. I plan on posting the information on my site and maybe cowanrq will use it too.
Operation: Big Screen
In an attempt to add a bit more science to the project, has anyone actually documented the temperatures produced by their projectors and projector bulbs? I'd like to see a comparison for relative heats for a range of setups. If you have ENX, FXL, Metal Hallide, whatever, what are the typical temps they produce, what cooling is needed, and if anybody knows, the temps when they just decide to blow!
I'm gonna pick up one of these guys from radio shack to measure temperature for our setup and post results.
Any info you gather, let me know. I plan on posting the information on my site and maybe cowanrq will use it too.
Operation: Big Screen
SuperZoboo,
sounds like a good idea. it gets really important in case design if someone needs a LOT of cooling, as compared to just a tiny bit. just let me know when you have something for me.
im going to be doing a HUGE HUGE HUGE site update this weekend, so everyone take note. sorry i haven't been around lately, but ive just gotten really fed up with this forum, maily the people that post in it.
sounds like a good idea. it gets really important in case design if someone needs a LOT of cooling, as compared to just a tiny bit. just let me know when you have something for me.
im going to be doing a HUGE HUGE HUGE site update this weekend, so everyone take note. sorry i haven't been around lately, but ive just gotten really fed up with this forum, maily the people that post in it.
I know how you feel, cowan. It's hard enough to sift through the mountains of information on this thread even without the 2-3 ******* that keep trading elementary barbs and clogging it up for those of us who are here to share ideas.
BTW, your site's been very useful to me. It's the first one I link to people now when I try to explain to them what I'm building.
My ballast is hopefully arriving today, so I should be able to finally get started on some real progress!
BTW, your site's been very useful to me. It's the first one I link to people now when I try to explain to them what I'm building.
My ballast is hopefully arriving today, so I should be able to finally get started on some real progress!
Folks, it has been brought to my attention (seein' as how I'm the Moderator) that some people are behaving, shall we say, rather poorly in this thread.
Now, setting aside the fact that this is a site dedicated to building your own gear and that posts calling people names and such don't advance the cause, you're also burning bandwidth for people who have to wait for modems to deliver the bits & bytes. Diagrams are useful for showing what you're talking about...that's cool. But posting 'art' and reworking old coffee posters? Not cool. Doesn't fly.
You don't have to like each other--you can hate each other for all I care--but keep the tone here at DIY suitable for a G rating. If you want to flame each other in e-mail, that's peachy, just don't do it here. This thread is quite long enough without having to wade through 10% insults and profanity.
Speaking as an author, it looks as though certain people should consult a dictionary. Misspelled words can make you look even more immature than the content of your posts...and in some cases that's very immature indeed.
Grey
Now, setting aside the fact that this is a site dedicated to building your own gear and that posts calling people names and such don't advance the cause, you're also burning bandwidth for people who have to wait for modems to deliver the bits & bytes. Diagrams are useful for showing what you're talking about...that's cool. But posting 'art' and reworking old coffee posters? Not cool. Doesn't fly.
You don't have to like each other--you can hate each other for all I care--but keep the tone here at DIY suitable for a G rating. If you want to flame each other in e-mail, that's peachy, just don't do it here. This thread is quite long enough without having to wade through 10% insults and profanity.
Speaking as an author, it looks as though certain people should consult a dictionary. Misspelled words can make you look even more immature than the content of your posts...and in some cases that's very immature indeed.
Grey
a little on temperature monitoring...
what i am in the process of doing, is making a simple thermostat-relay logic circuit. this is so that the projector will shut down (or not start up) if the lcd's glass is hotter than a predetermined/set upper threshold. you can pick up preset thermostas, or cheap programmable ones (with cool lcd displays) from most electronics supply stores (well you can here in australia anyway, i.e. jaycar altronics, etc...). then it's only a matter of making a simple logic circuit, with some relays, and bob's yer uncle... or whatever
what i am in the process of doing, is making a simple thermostat-relay logic circuit. this is so that the projector will shut down (or not start up) if the lcd's glass is hotter than a predetermined/set upper threshold. you can pick up preset thermostas, or cheap programmable ones (with cool lcd displays) from most electronics supply stores (well you can here in australia anyway, i.e. jaycar altronics, etc...). then it's only a matter of making a simple logic circuit, with some relays, and bob's yer uncle... or whatever
Sweet!
I just received my surplus projection lens from edmundoptical.com...that thing is a beast! I'll try to post a picture of it that shows how massive it is. It's in great condition, too. Should be fun to experiment with.
I just received my surplus projection lens from edmundoptical.com...that thing is a beast! I'll try to post a picture of it that shows how massive it is. It's in great condition, too. Should be fun to experiment with.
setup
😕
I have been diong some thinking. ( i know, to much thinking and not enough tinkering!)
Up till now it seems that everyone has been using either 1 ferensl lens or a pair of matched ferensls to condense the beam of light. This seems to lead to excessive projector sizes.
Wouldn't it be possible to use, for example, one ferensl lens with a 6" fl with the light at the focus paired with one with a 12" fl to focus the beam back down to the objective lens through the lcd?
This would allow us to use a higher % of the light from the bulb and still have a decently wide beam of light for the lcd. (i.e. the polarizer on the lcd only passes parallel light beams so the angle of the light from the condenser cannot be to steep.)
It would also allow for smaller housings.
The only problem I can see with this is the increased amount of heat on the ferensls.
😀
😕
I have been diong some thinking. ( i know, to much thinking and not enough tinkering!)
Up till now it seems that everyone has been using either 1 ferensl lens or a pair of matched ferensls to condense the beam of light. This seems to lead to excessive projector sizes.
Wouldn't it be possible to use, for example, one ferensl lens with a 6" fl with the light at the focus paired with one with a 12" fl to focus the beam back down to the objective lens through the lcd?
This would allow us to use a higher % of the light from the bulb and still have a decently wide beam of light for the lcd. (i.e. the polarizer on the lcd only passes parallel light beams so the angle of the light from the condenser cannot be to steep.)
It would also allow for smaller housings.
The only problem I can see with this is the increased amount of heat on the ferensls.
😀
howto online
with what Krazzyed & I have learned from this forum and our results we have posted a quick "howto" on our site. it gives instructions and breaks the project into several categories.
ill finish up the howto this weekend, but for now the "easy method" is up, which is what we've done so far and are very happy with the results!
any comments and feedback are welcome. just use the email's listed on the site.
with what Krazzyed & I have learned from this forum and our results we have posted a quick "howto" on our site. it gives instructions and breaks the project into several categories.
ill finish up the howto this weekend, but for now the "easy method" is up, which is what we've done so far and are very happy with the results!
any comments and feedback are welcome. just use the email's listed on the site.
I see where this is going
Well Im not going to be reading through all the crap any more. This is my last post here unless an admin can take care of his fourm like a good admin should. Good luck to you all!!
Well Im not going to be reading through all the crap any more. This is my last post here unless an admin can take care of his fourm like a good admin should. Good luck to you all!!
SIGH...
omg, as long as Vince was posting in this forum, it was all going well. Now everything is going down the drain and there's not a single person who wants to take charge and fix it.
what progress have we achieved in the last month? none, none at all. before that, at least we had some people trying.
aleksey🙁 🙁 🙁
omg, as long as Vince was posting in this forum, it was all going well. Now everything is going down the drain and there's not a single person who wants to take charge and fix it.
what progress have we achieved in the last month? none, none at all. before that, at least we had some people trying.
aleksey🙁 🙁 🙁
Friends, don't fail me now...
I been making slow but sure progress with my projector setup, and many of your have been wonderfully helpful in getting where I am today: I've just taken the $100 leap, and purchased the 400 watt metal Halide lamp for the project.
Here's a picture attached.
Now I've got to wire it together, and see how it operates. Can anyone suggest how long a "test" I can get away with before I start working on the cooling system? Clearly, I've got to get airflow via fans and ducts, but I need to set it up and see how it's working. 2 minutes? 5 minutes?
I'll take the guts out of the OHP, and take more pix.
dave
PS: let's stay on topic, OK team?
I been making slow but sure progress with my projector setup, and many of your have been wonderfully helpful in getting where I am today: I've just taken the $100 leap, and purchased the 400 watt metal Halide lamp for the project.
Here's a picture attached.
Now I've got to wire it together, and see how it operates. Can anyone suggest how long a "test" I can get away with before I start working on the cooling system? Clearly, I've got to get airflow via fans and ducts, but I need to set it up and see how it's working. 2 minutes? 5 minutes?
I'll take the guts out of the OHP, and take more pix.
dave
PS: let's stay on topic, OK team?
Attachments
If that's a Metal Halide, why does the box say Mercury Vapor?
PS: I don't wanna beat a dead horse, but I agree with prjctr_builder, SuperZoboo, and Marklar. Somebody should delete some of this junk. It's getting out of hand.
PS: I don't wanna beat a dead horse, but I agree with prjctr_builder, SuperZoboo, and Marklar. Somebody should delete some of this junk. It's getting out of hand.
If you don't want to see a particular person's posts, click the Profile button at the bottom of one of their posts. In the new window which appears, click Add Person To Ignore List which is at the very bottom of the table of information. You'll be told that this person has been added to your ignore list, and you can now close the profile window, return to the main forum, press Refresh, and lo and behold their postings have been zapped.
HTH
Jernau
HTH
Jernau
Here should not come up hystery and panic !!
It's clear, the more actors appear on the stage, the more different characters and interests have to be balanced. Every experienced forum or newsgroup user knows, each forum has it's opinion leaders, it's guards and it's clowns. May be this thread here is too big to match all interests and breaks down under it's own gravity, it's already a dino. Quantity doesn't mean quality, as everybody knows.
On the other hand, the 'flame' ratio over all the time isn't that bad exept a couple of days. At least, i think the real interest, builting DIY-projecters will dominate over some clownesque attitudes!!
xblocker
It's clear, the more actors appear on the stage, the more different characters and interests have to be balanced. Every experienced forum or newsgroup user knows, each forum has it's opinion leaders, it's guards and it's clowns. May be this thread here is too big to match all interests and breaks down under it's own gravity, it's already a dino. Quantity doesn't mean quality, as everybody knows.
On the other hand, the 'flame' ratio over all the time isn't that bad exept a couple of days. At least, i think the real interest, builting DIY-projecters will dominate over some clownesque attitudes!!
xblocker
Ya scared me...
Noodles,
I read your question, and zoomed back into the workshop. The big print actually says "GE Multi-Vapor Lamp", and above it in smaller print it says Metal Halide.
Whew.
dave.
Noodles,
I read your question, and zoomed back into the workshop. The big print actually says "GE Multi-Vapor Lamp", and above it in smaller print it says Metal Halide.
Whew.
dave.
Hello all, from colorado I post 🙂
First of all, for those who said no progress has been made, I remind you that I will have a finished working projector within 2 weeks 🙂
As for the Multi-Vapor labeling on the metal halide bulb, I'm pretty sure that all Metal Halide bulbs say this (most of the time it being the largest print on the box).
daveb: almost all metal halide bulbs will be fine out in the open air, without any fans or cooling whatsoever. You can run them for hours and hours. The only time you have to worry about cooling is when you've got aluminum or mirrors, or whatever surrounding it, keeping the heat within a small fixture that the bulb is in.
First of all, for those who said no progress has been made, I remind you that I will have a finished working projector within 2 weeks 🙂
As for the Multi-Vapor labeling on the metal halide bulb, I'm pretty sure that all Metal Halide bulbs say this (most of the time it being the largest print on the box).
daveb: almost all metal halide bulbs will be fine out in the open air, without any fans or cooling whatsoever. You can run them for hours and hours. The only time you have to worry about cooling is when you've got aluminum or mirrors, or whatever surrounding it, keeping the heat within a small fixture that the bulb is in.
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