Hi folks,
Just a quick question or two for you. I recently bought an Eiko 250w double ended metal halide lamp for use in my projector build. I've since found it to be unshielded to UV rays and - seeing as I don't have a UV stop of any type - figured it'd be unsafe to use.
I've now sought advice from the local electrical shop and bought a GE MQI/250/T8/43 . The suppliers assure me it is UV shielded, however everything I read demands the lamp to be used within an enclosure with adequte UV shielding.
My question is this: do the lamps with UV stops still recommend using in a UV shielded enclosure? Am I getting overly concerned about the warnings on the box?
Finally - Can anybody direct me towards a company (preferably UK based) that can provide me with a UV stop of some description, encase I cannot resolve the issue at the lamp level.
Apologies if any part of this has been asked before, I couldn't find the answers. Many thanks.
Just a quick question or two for you. I recently bought an Eiko 250w double ended metal halide lamp for use in my projector build. I've since found it to be unshielded to UV rays and - seeing as I don't have a UV stop of any type - figured it'd be unsafe to use.
I've now sought advice from the local electrical shop and bought a GE MQI/250/T8/43 . The suppliers assure me it is UV shielded, however everything I read demands the lamp to be used within an enclosure with adequte UV shielding.
My question is this: do the lamps with UV stops still recommend using in a UV shielded enclosure? Am I getting overly concerned about the warnings on the box?
Finally - Can anybody direct me towards a company (preferably UK based) that can provide me with a UV stop of some description, encase I cannot resolve the issue at the lamp level.
Apologies if any part of this has been asked before, I couldn't find the answers. Many thanks.
Need not worry about UV me thinks simply because the LCD consumes so much light, and UVC(most dangerous) will not penertrate Glass(eg, wont get past your projection lens) however, UVB and UVA will with only minimal deductions(penertrate glass that is..) - but providing your cabinet has no light leakage then this shouldnt be an issue either due to how much light the LCD absorbs(or fails to pass for lack of a better term) ... somewhere in the vicinity of 10% at BEST out the projection lens, then once it hits the screen only minimal amounts once agian are actaully reflected(depending on screen gain) .. so in short, yah I dont really think its a issue, but seeing as UV filters are so cheap, your silly not to try and protect yourself and your family, you only get one set of eyes.
I'd say one of the best/cheapest options is standard glass$(5NZ)with the automotive type clear UV filter$(5NZ) (similer to tint film) applied. - bout $7 US in totel.
Im not too sure if UVA - C - B can actaully penertrate wood etc..but im pretty damn sure it can.. it would probebly be better to be safe than sorry and put some sort of metal enclosure around the bulb, or sheets of sheet metal on the inside of your projector.
[edit] to answer your other question, I had a 400w Syvlania Bulb, that had a huge UV stop envolope, and it actaully said on the packaging, UV stop envolope, and it still suggested that a UV Stop be used(they suggested a standard difuser, like used in flourencents.. the plastic cover is the diffuser i believe. [/edit]
I'd say one of the best/cheapest options is standard glass$(5NZ)with the automotive type clear UV filter$(5NZ) (similer to tint film) applied. - bout $7 US in totel.
Im not too sure if UVA - C - B can actaully penertrate wood etc..but im pretty damn sure it can.. it would probebly be better to be safe than sorry and put some sort of metal enclosure around the bulb, or sheets of sheet metal on the inside of your projector.
[edit] to answer your other question, I had a 400w Syvlania Bulb, that had a huge UV stop envolope, and it actaully said on the packaging, UV stop envolope, and it still suggested that a UV Stop be used(they suggested a standard difuser, like used in flourencents.. the plastic cover is the diffuser i believe. [/edit]
Guys,
The most important thing to protect (aside from your eyes) is your most expensive component--that being the LCD panel. UV rays are an LCD KILLER! it will turn black in a relatively short time. The UV envelop on the lamp should be sufficient but you don't want to "not worry" about it getting absorbed by the LCD panel. The cheapest way is to use XL10 lexan/plexiglass from your local home improvment store and place it in the light path twix the light engine and the LCD panel. Alternatively, the regular glass outfitted with the clear UV protectant from an autoshop is a good idea.
Steamer
The most important thing to protect (aside from your eyes) is your most expensive component--that being the LCD panel. UV rays are an LCD KILLER! it will turn black in a relatively short time. The UV envelop on the lamp should be sufficient but you don't want to "not worry" about it getting absorbed by the LCD panel. The cheapest way is to use XL10 lexan/plexiglass from your local home improvment store and place it in the light path twix the light engine and the LCD panel. Alternatively, the regular glass outfitted with the clear UV protectant from an autoshop is a good idea.
Steamer
XL10 lexan-whats it look like?
Hey is there an easy way to tell this from any other clear plastic sheet? I know it's coated on one side, can you see a difference? Unfortunately where I live corruption is the rule not the exception. I'd hate to not only get ripped off but ruin an lcd too.
Hey is there an easy way to tell this from any other clear plastic sheet? I know it's coated on one side, can you see a difference? Unfortunately where I live corruption is the rule not the exception. I'd hate to not only get ripped off but ruin an lcd too.
XL10 can be found at your local Home Depot, or Lowes. You should be able to ask a floor staffperson to direct you to the XL10 and it should be labeled or something. Of course, this is merely conjecture, as I have yet to go thru this process myself. I will try to go and obtain a piece tomorrow and hopefully I can be better informed. You, in turn, will become better informed as a result.
Steamer
Steamer
Re: XL10 lexan-whats it look like?
Welcome to america he says.... perhaps that was a tad harsh.
if thats the case, best idea for sure, is get a standard peice of thin glass and put the UV film on it, both sides if you wished.
justme said:
Welcome to america he says.... perhaps that was a tad harsh.
if thats the case, best idea for sure, is get a standard peice of thin glass and put the UV film on it, both sides if you wished.
Re: Re: XL10 lexan-whats it look like?
That's OK, we don't mind... people always take pot shots at you when you are #1!
The Lexan is clearly marked on the film protecting the coated side so you cannot mistake it.
ELiTeHaYDeN said:
That's OK, we don't mind... people always take pot shots at you when you are #1!
The Lexan is clearly marked on the film protecting the coated side so you cannot mistake it.
Aslong as thats all taken as a joke...........
Guys to be quite honest if your bulb has a UV stop you dont need the lexan. The UV stop thats built into the bulb blocks 70% and up of the UV, the frensels also block UV. A condenser (unless its upto UV spec) will also block UV light.
Unless you are using the 100% of the light from your source (which imo is practically impossible in our setups), you will never have that 30% of UV hit your lcd. All lexan will basically do is cost you light and its advisable to get a PROPER UV filter to filter the UV light from an UNPROTECTED bulb.
The reason UV block came about in bulbs is because of food and human saftey in shopping malls. Bulbs that are unprotected will discolour food and give people a tan. I have never ever gotten a tan from my 250w HQI-TSD UV protected bulb yet, and beleive me ive spent hrs infront of it. A human being will tan before an lcd, so will food.
Trev🙂
Just frustrated
Well that was interesting. I was actually just talking about the city and surrounding area not the whole country. I was just a bit irritated after dealing with some of the local busineses here.
Let me explain what I'm doing. Since this will be my first pj I'm going to use a 5.6" TV type low res (regardless of what they claim) LCD and the lamp & condensor from an old slide projector. The only new stuff will be the triplet and some fresnels from an office supply store. The plan is to build this one, likely into an old pc case, play with it for a while and then with what skills learned build a higher resolution, brighter and better planned pj. This way if I screw up the LCD it only a cheap one and not something I paid $200+ for. I would still like to be able to reassemble the little monitor and use it for something else so the cost of a small piece of glass or plexiglass is worth it. The lamp for this project is only powerful enough to be able to be used if the room is dark so the less light lost the better. The XL10 being clearly marked is the main info I was lookin for.
thanks
Well that was interesting. I was actually just talking about the city and surrounding area not the whole country. I was just a bit irritated after dealing with some of the local busineses here.
Let me explain what I'm doing. Since this will be my first pj I'm going to use a 5.6" TV type low res (regardless of what they claim) LCD and the lamp & condensor from an old slide projector. The only new stuff will be the triplet and some fresnels from an office supply store. The plan is to build this one, likely into an old pc case, play with it for a while and then with what skills learned build a higher resolution, brighter and better planned pj. This way if I screw up the LCD it only a cheap one and not something I paid $200+ for. I would still like to be able to reassemble the little monitor and use it for something else so the cost of a small piece of glass or plexiglass is worth it. The lamp for this project is only powerful enough to be able to be used if the room is dark so the less light lost the better. The XL10 being clearly marked is the main info I was lookin for.
thanks
If your going to be using a halogen make sure you use a UV filter or your lcd will go black forsure. Use a IR filter aswell.
Trev🙂
Trev🙂
Did you mean me?
ace3000_1
If the warning about the halogen was directed towards me theres no need to worry.
The slide pj lamp is incandescent and since I have no idea as to what non-visable light it puts out I plan on a UV filter of some kind. Strangely enough with the huge amount of light it puts out the test slide I made by printing out a kind of test pattern on a regular piece of paper didn't seem to warm up very much at all, maybe because it's almost a foot away from the lamp.
ace3000_1
If the warning about the halogen was directed towards me theres no need to worry.
The slide pj lamp is incandescent and since I have no idea as to what non-visable light it puts out I plan on a UV filter of some kind. Strangely enough with the huge amount of light it puts out the test slide I made by printing out a kind of test pattern on a regular piece of paper didn't seem to warm up very much at all, maybe because it's almost a foot away from the lamp.
Ya well they dont put out much light thats why , dont forget a lcds polarisers absorb light so heat bulds up.
For that lcd an incondesent light wont be bright enough. The setup i had (when i once used a 6inch lcd) had a 150w halogen with 2 peices of uv grade plexi wedging the frensels as a uv filter, the lcd still went black. Thats why i tell people to use the proper filters because uv grade plexi wont be enough, neither will glass.
Trev🙂
dismember old lcd projector?
Well I bought an old boxlight projector that uses a 250 watt MH lamp (from what I've been able to find out), maybe if I can figure out what part of the innards is the ballast I could use that, One of the lcds seems to be shot so unless I can find the same model cheap with working lcds it's just taking up room. The wiring is pretty simple since it was built around a pc case format and there seem to be only a few that carry much juice. It also seems to have lots of UV and IR protection I could use as well. This way I could at least get my $35 worth out of it.
Well I bought an old boxlight projector that uses a 250 watt MH lamp (from what I've been able to find out), maybe if I can figure out what part of the innards is the ballast I could use that, One of the lcds seems to be shot so unless I can find the same model cheap with working lcds it's just taking up room. The wiring is pretty simple since it was built around a pc case format and there seem to be only a few that carry much juice. It also seems to have lots of UV and IR protection I could use as well. This way I could at least get my $35 worth out of it.
Ace, did the LCD go black because of the UV output from the 150w Halogen lamp? I thought that these put out miniscule amounts of UV when compared to a Metal Halide Lamp, and if your LCD still when black then it sounds like lexan REALISTICALLY does **** all other than eat a little bit more light.
Quick off topic question :
I have ordered and have on its way a 400w HQI Light kit from Astaples, he doesnt state weither its UV blocking or not? whats the best protection for that then? will the peice of glass and UV film simply not be enough?
Quick off topic question :
I have ordered and have on its way a 400w HQI Light kit from Astaples, he doesnt state weither its UV blocking or not? whats the best protection for that then? will the peice of glass and UV film simply not be enough?
Re: dismember old lcd projector?
if the lamp was relativly small form factor could you not use this? eg, attempt to use the entire light box ..
justme said:
if the lamp was relativly small form factor could you not use this? eg, attempt to use the entire light box ..
Ya nothing else would of made it black, i didnt paint it thats for sure lol. The colours changed aswell the yellow and green wer faded and the blue went darker. I didnt use the projector much, about 500hrs in total, i remeber the lamp i used gave me a good tan in 30mins.
Im not sure what that UV film is like but its a good start. Edmund optics among others sell the filters, you only need a small one.
The 400w HQI from Allan Staples is not UV blocked.
Trev🙂
No cos they are DC rated and they wont carry the same voltage or amperage as the AC rated lamps we use. If you did mannage to get it going it will also take the life out of your lamp as it will burn the cathade electrode out.
Trev🙂
I was unclear
I have a feeling that I wasn't very clear about what I was planning. The idea is to use the entire "light engine" from this projector including the lamp & reflector. Just mount it and all the cards in a larger case (with the cards out of the light path of course). I know from messing around with it that the lamp will function without the LCDs, TV tuner/composite input card and the VGA in/out card. Just use it as a light source. Since the fl of the condensor, fresnels and objective are longer and the LCD is larger I will need a much larger case anyway,(even using mirrors).
Here'e what I'm looking at:
I have a feeling that I wasn't very clear about what I was planning. The idea is to use the entire "light engine" from this projector including the lamp & reflector. Just mount it and all the cards in a larger case (with the cards out of the light path of course). I know from messing around with it that the lamp will function without the LCDs, TV tuner/composite input card and the VGA in/out card. Just use it as a light source. Since the fl of the condensor, fresnels and objective are longer and the LCD is larger I will need a much larger case anyway,(even using mirrors).
Here'e what I'm looking at:
Attachments
It still wont work because the light in these things are condensed and they are made to illuminate 1.8" lcd's only. They are custom made to be this way and it goes right back to the reflector.
If its got an elliptical reflector no problem, but if its a parabollic (in most cases) you wont have a chance.
Trev🙂
If its got an elliptical reflector no problem, but if its a parabollic (in most cases) you wont have a chance.
Trev🙂
- Status
- Not open for further replies.