Hello!
I have the Pro fresnel lenses and a triplet lense that I bought off of eBay. As I understand it, the pro condenser lens has Dimensions: 431 X 406 X 2mm and Focal Length: 220mm. The pro field lense is Dimensions: 431 X 406 X 2mm and Focal Length: 650mm.
My triplet is 5" diameter and has a focal length of 12". (304.8mm)
What I want to know is if this setup will work - will the lcd image fit entirely into my triplet, or will it be cut off?
here's a badly drawn picture to illustrate my concerns.
Click to view attachment
Full Version: I don't know if my fresnels and triplet will match up!
The 300mm triplet will not work in this situation. There is just too much of a discrepancy between the FL of hte collector fresnel, and the FL of the triplet.
By increasing the distance from lamp to collimator you MIGHT make this work but at a large cost in light output.
BTW, the throw on that projector will be VERY short. The standard triplet is 320mm FL, and it's too short (IMO) for use with a 17" monitor.
3dlens.com will have a large fresnel of 330mm FL, that can be used as the collector in this case. But unless your LCD is 15" or smaller, I would not recommend that triplet. (Also in that case, I would recommend the standard fresnel lens kit.)
Post the pro fresnels in the trading post. Heck if they're unopened, and fingerprint free, tell me what you paid for 'em.
By increasing the distance from lamp to collimator you MIGHT make this work but at a large cost in light output.
BTW, the throw on that projector will be VERY short. The standard triplet is 320mm FL, and it's too short (IMO) for use with a 17" monitor.
3dlens.com will have a large fresnel of 330mm FL, that can be used as the collector in this case. But unless your LCD is 15" or smaller, I would not recommend that triplet. (Also in that case, I would recommend the standard fresnel lens kit.)
Post the pro fresnels in the trading post. Heck if they're unopened, and fingerprint free, tell me what you paid for 'em.
QUOTE (SupraGuy @ Feb 1 2006, 11:20 PM) 
The 300mm triplet will not work in this situation. There is just too much of a discrepancy between the FL of hte collector fresnel, and the FL of the triplet.
By increasing the distance from lamp to collimator you MIGHT make this work but at a large cost in light output.
BTW, the throw on that projector will be VERY short. The standard triplet is 320mm FL, and it's too short (IMO) for use with a 17" monitor.
3dlens.com will have a large fresnel of 330mm FL, that can be used as the collector in this case. But unless your LCD is 15" or smaller, I would not recommend that triplet. (Also in that case, I would recommend the standard fresnel lens kit.)
Post the pro fresnels in the trading post. Heck if they're unopened, and fingerprint free, tell me what you paid for 'em.
By increasing the distance from lamp to collimator you MIGHT make this work but at a large cost in light output.
BTW, the throw on that projector will be VERY short. The standard triplet is 320mm FL, and it's too short (IMO) for use with a 17" monitor.
3dlens.com will have a large fresnel of 330mm FL, that can be used as the collector in this case. But unless your LCD is 15" or smaller, I would not recommend that triplet. (Also in that case, I would recommend the standard fresnel lens kit.)
Post the pro fresnels in the trading post. Heck if they're unopened, and fingerprint free, tell me what you paid for 'em.
ok then... i guess that's a little dissapointing.
could it be possible that the pro fresnels would work with the standard LL triplet?Maybe i should sell this triplet to someone with a small LCD - it'd be like a Pro lens to them then.
One last grasp - will the pro lenses work for me if i cut them to the size of my 17" lcd? Also - how short is short throw? I'm just grasping at straws here...
Supra - Curious, why wouldn't you recommend using his triplet? It's much larger in diameter. Wouldn't that help with imaging a larger 17" LCD?
I think what Supra meant was that he could either change the fresnel to a shorter focal length (around 300-ish mm) and keep the current triplet, or keep the current fresnel and buy a pro lens. Getting a new fresnel is a lot cheaper than buying the pro lens.
QUOTE (EdZ @ Feb 2 2006, 12:30 PM)
I think what Supra meant was that he could either change the fresnel to a shorter focal length (around 300-ish mm) and keep the current triplet, or keep the current fresnel and buy a pro lens. Getting a new fresnel is a lot cheaper than buying the pro lens.
OK i remembered the focal calculator. Maybe this will help me?
Click to view attachment
Anyone know if this will work out? >light spillage?
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