I would for sure pre-order a lens if thats what you needed! Its been a real pain for me trying to find a reasonably priced lens without buying another OHP just to take one out of! Let us know what you decide!
Condenser Lens Decision
Hello all!
I have decided to offer the condenser lens as a group order on www.diylabs.org. I will accept pre-orders at a discounted rate in order to raise enough money to order the lenses for the entire group. Basically, if you purchase from the group order, then you will be getting the condenser lens at my actual cost ($10) - I appreciate everyone's support. After I have ordered the lenses, the price will go up to just $15, so you'd be saving $5 by purchasing from the group order.
If for some reason I am unable to raise enough money to make the order, then everyone will have their money refunded in full. Please email me at diylabs@hotmail.com if you have any comments or questions about this method of purchasing condenser lenses. Hopefully this works out nicely so that everyone can get a great new lens without spending much money!
Hello all!
I have decided to offer the condenser lens as a group order on www.diylabs.org. I will accept pre-orders at a discounted rate in order to raise enough money to order the lenses for the entire group. Basically, if you purchase from the group order, then you will be getting the condenser lens at my actual cost ($10) - I appreciate everyone's support. After I have ordered the lenses, the price will go up to just $15, so you'd be saving $5 by purchasing from the group order.
If for some reason I am unable to raise enough money to make the order, then everyone will have their money refunded in full. Please email me at diylabs@hotmail.com if you have any comments or questions about this method of purchasing condenser lenses. Hopefully this works out nicely so that everyone can get a great new lens without spending much money!
I got the Powerstar Hqi kit from a lighting store here in Argentina.
It was a demo model but he gave me a new bulb when I asked.
The ballast is big and heavy about 12 inches long by 3 inches wide and 3 inches high. I would guess it weighs 5 or 6 kilos. I figured I could place it outside of the projector so I didnt care.
The sockets came pre installed within the reflector housing which inturn was covered by plate of glass. The lamp/reflector head is very light. I even bought it prewired to the ballast. $23 everything. New would have been $65. Still a great deal. The ballast is made by a Argentinian company. It has some numbers on there I dont understand but it looks like it will power up to a 1000k bulb. I asked about the option of a 250 watt hqi but they just showed me this huge single ended thing.
Is the 250 watt hqi bulb larger? I mean do I need different
sockets and a larger reflector housing or is it just fatter in the center?
It was a demo model but he gave me a new bulb when I asked.
The ballast is big and heavy about 12 inches long by 3 inches wide and 3 inches high. I would guess it weighs 5 or 6 kilos. I figured I could place it outside of the projector so I didnt care.
The sockets came pre installed within the reflector housing which inturn was covered by plate of glass. The lamp/reflector head is very light. I even bought it prewired to the ballast. $23 everything. New would have been $65. Still a great deal. The ballast is made by a Argentinian company. It has some numbers on there I dont understand but it looks like it will power up to a 1000k bulb. I asked about the option of a 250 watt hqi but they just showed me this huge single ended thing.
Is the 250 watt hqi bulb larger? I mean do I need different
sockets and a larger reflector housing or is it just fatter in the center?
Metal halide ballasts will generally only work with 1 specific type of bulb that it was made for, so the "will work with up to 1000 watt bulb" part isn't really a consideration. The 250 watt HQIs that I sell are double-ended and about 6.5" long - pretty small. Also, you need to realize that a reflector is only effective if it is equal to or smaller in diameter than the projection lens. This is because the light is now coming from the bulb and the reflector, so the system needs to be small enough to still be considered a "point source" even though it isn't technically a point source. It doesn't hurt anything to use a larger reflector, but only the small part of the reflector that is within an inch or so of the bulb will actually do any work. The only exception to this is if you are using a special reflector that directs all of the light into a small region where you can put a condenser lens, but this type of setup takes up a lot of space and I'm not sure if it is really any brighter than using a 250 watt HQI without a condenser (using a condenser would make it even brighter, of course).
As far as I can understand, projection lens is just a heat-resitant lens (plano-convex or concave-convex, I suppose) with very short focal length, that should gather all the light from the bulb and reflector to a point, and this point should be in the focus of the first fresnel, right? Does the diameter of the lens matter? How big should be the lens regarding to the diameter of the reflector?
The condencer lens should be a meniscus (an object like the half moon), in other words a concave-convex lens with a short positive focal length (about 100 mm or 4" or so). The diameter should be large enough to cover the bulb (or lamp) enough to gather the light that is otherwise wasted.
Actually both reflector and condencer should be as large as possible, but we should talk about degrees of circle that they cover around the lamp, diameter depends on how close to lamp they are. Ideally both are 180 degrees or half balls, and the bulp is in the origo of that ball.
Alan (if you're reading this), have you found any good source for reflectors yet? YWH (where is he?) once was selling them for $10 but because he lives in China it may be difficult to sell them us (if he could just send them Alan to be sold).
Have anyone considered how to build a light assembly that could be adjusted? Some OHP's some have this kind of feature meant to help adjusting the light (brightness) when the OHP is moved further from the screen and thus the light from the fresnel doesn't make it to the projection lens anymore.
Actually both reflector and condencer should be as large as possible, but we should talk about degrees of circle that they cover around the lamp, diameter depends on how close to lamp they are. Ideally both are 180 degrees or half balls, and the bulp is in the origo of that ball.
Alan (if you're reading this), have you found any good source for reflectors yet? YWH (where is he?) once was selling them for $10 but because he lives in China it may be difficult to sell them us (if he could just send them Alan to be sold).
Have anyone considered how to build a light assembly that could be adjusted? Some OHP's some have this kind of feature meant to help adjusting the light (brightness) when the OHP is moved further from the screen and thus the light from the fresnel doesn't make it to the projection lens anymore.
The condenser lens should be large enough to cover the entire light source part of the lamp (the inner arc tub in the case of metal halides), but that lens should NOT be any larger than the projection lens, otherwise not all of the light output will converge back onto the backside of the projection lens. Typically larger projection lenses are better, but I definitely don't recommend going any smaller than 60mm. As long as your light source is of a reasonably small size, a 70mm lens is big enough to use efficiently, but you can always go larger. One thing though, be aware that the Fujinon lenses that many people have been asking me about are only good for use with LCD panels that are smaller than the diameter of the projection lens. This is because those lenses need to be nearly in contact with the source in order to be in focus. The projection triplet lenses that are becoming more popular can focus a 15" LCD panel entirely without any problems or artifacts.
I'll start offering the DIY reflector on my website, but I have no plans to offer any of YWH's reflectors unless he has different ones now. The ones that he had were far too small and were only about 20 degrees of a sphere instead of a crude 180 degrees like my reflectors. The reflector I have will be $7 plus shipping. It will only work with bulbs that are at most 1-7/8" maximum diameter.
I'll start offering the DIY reflector on my website, but I have no plans to offer any of YWH's reflectors unless he has different ones now. The ones that he had were far too small and were only about 20 degrees of a sphere instead of a crude 180 degrees like my reflectors. The reflector I have will be $7 plus shipping. It will only work with bulbs that are at most 1-7/8" maximum diameter.
Hey Alan,
Is that the reflector I bought from you?
My stuff has not arrived yet. No sweat though, as long as they arrive 😉 (although I do get a bit worried when there are delays
).
Man, now I just wish I had an LCD instead of this lame Projection Panel. You know what happened guys? This weird WEIRD panel just started turning on macrovision on my VGA signal! And I have no idea why, macrovision was never on when I was using VGA before!!
I hope we can get some more information on where to get those 8" LCD's that all Koreans seem to use 🙂 . Because even though they can only do 800*600, that is MORE then enough for me..
Is that the reflector I bought from you?
My stuff has not arrived yet. No sweat though, as long as they arrive 😉 (although I do get a bit worried when there are delays
).Man, now I just wish I had an LCD instead of this lame Projection Panel. You know what happened guys? This weird WEIRD panel just started turning on macrovision on my VGA signal! And I have no idea why, macrovision was never on when I was using VGA before!!
I hope we can get some more information on where to get those 8" LCD's that all Koreans seem to use 🙂 . Because even though they can only do 800*600, that is MORE then enough for me..
hey taku,
about the SGVA lcd thing...i thinks its ENOUGH for you and probably me but its not MORE than enough...thats reserved to UXGA and up 😀 and keep in mind those are 300$!! and u have to order in 50's
i think alan can find cheap LCD solutions for us, after all he IS the DIY pimp 😎 lol 🙂
about the SGVA lcd thing...i thinks its ENOUGH for you and probably me but its not MORE than enough...thats reserved to UXGA and up 😀 and keep in mind those are 300$!! and u have to order in 50's
i think alan can find cheap LCD solutions for us, after all he IS the DIY pimp 😎 lol 🙂
Alan,
How do I find out if my ballast can take your 250 watt hqi bulb?
I mean just power it?
Should I take some photos of it and send them to you Alan or post them here?
How do I find out if my ballast can take your 250 watt hqi bulb?
I mean just power it?
Should I take some photos of it and send them to you Alan or post them here?
Takusama said:
taco heres an LCD thats widescreen and under 300$ and comes with remote 🙂 im not sure about cntrast but i think it 200:1
http://store.yahoo.com/1hitwonders/700v.html
check this thread out http://www.diyaudio.com/forums/showthread.php?s=&threadid=3634&perpage=40&pagenumber=3
sushi claims this LCD is SVGA if its true then we have a good deal on our hands 🙂 http://www.avdeals.com/marshall/lcdPanel/vlcd1.8p.htm
and this... http://www.anycities.com/sushimasterx/2002.html i dont know if this is fomr is projector or not..but very interesting...
sushi claims this LCD is SVGA if its true then we have a good deal on our hands 🙂 http://www.avdeals.com/marshall/lcdPanel/vlcd1.8p.htm
and this... http://www.anycities.com/sushimasterx/2002.html i dont know if this is fomr is projector or not..but very interesting...
Negative Design said:
The DIY pimp ... I like that ... yeah - das coo (best "Lady's Man" impression). I'll do my best to figure out some LCDs. I found a really cool one that was 8.4" 16:9 with a little over 900 pixels wide. The only problem is that I'd have to order at least 100 of them at $240 per panel! I simply don't have the cash to back that one. If I can find a manufacturer that will sell in quantities closer to 10 or even 50, then I might be able to get something going. I'm always welcome to suggestions about where to go to in case anyone has ideas.
dracul said:
The HQI bulb that I have requires an M80 or equivalent ballast. The eBallast that I offer works with any 250 watt metal halide lamp, but most ballasts are only rated for use with one specific type of MH lamp (i.e. "M80"). If your ballast says that it is an M80 ballast, then it will work fine. It is my experience that M80 ballasts are incredibly rare and hard to find, which is one of the reasons that I decided to carry the IceCap ballast that I have on www.diylabs.org. Feel free to send a photo or 2 or 3 over to astaples@diylabs.org if you want me to have a look at it.
Negative Design said:
Sorry... manufacturer says it's only 528x220 (and that's probably not even its "true" resolution)
http://www.lcdracks.com/panels/vlcd18p.html
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