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While in a sloooow search for a used UH480, are ther serial number that would indicate a more recent model. Do older uh480's not offer what more recent ones offer......coatings ect...

Kg
 

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Discussion Starter · #4 ·
You can also PM me directly if you like. :)

Serial numbers going back 2 years begin with 2100. Were you wanting to know the differences between the UH480 and UH380?
So, the 480 came after the 380 ? Two years ago ?
 

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The only thing I vaguely remember reading about changes to the UH480, was I think a case change, but IIRC the optics are the same, so there's no benefit to a newer UH480 or any performance difference. Now the UH380 was different, they changed the design (ie the UH480) in part at least, to deal with some reflection issues that arose with JVC projectors.
 

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Wasn't there a UH420 as well?
Stranger is right about the upgrade on this but it was called the UH440. We upgraded the UH380 with the new housings with the anti reflective material and angled the rear corrector lens. This helped eliminate some of the ghosting issues that people had with the UH380 and their JVC projectors. The optics didn't change unless you upgraded to the UH480.
 

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Stranger is right about the upgrade on this but it was called the UH440. We upgraded the UH380 with the new housings with the anti reflective material and angled the rear corrector lens. This helped eliminate some of the ghosting issues that people had with the UH380 and their JVC projectors. The optics didn't change unless you upgraded to the UH480.

IIRC, this retro-reflection issue was only noticeable if the angle of incidence to the screen was near zero; in other words, the projector and lens height were near the center of the screen height. In that installation, the reflection off the corrector went straight back to the projector optics ... and back through the 380 to the screen. In installations where the projector was higher (near the top of the screen), the Panamorph is tilted down so that the light path from the projector is directly through, and thereby also shifting the reflection from the corrector such that it was above the projector lens, therefore not creating the retro-reflection "ghosting." Does that sound right, John?
 

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IIRC, this retro-reflection issue was only noticeable if the angle of incidence to the screen was near zero; in other words, the projector and lens height were near the center of the screen height. In that installation, the reflection off the corrector went straight back to the projector optics ... and back through the 380 to the screen. In installations where the projector was higher (near the top of the screen), the Panamorph is tilted down so that the light path from the projector is directly through, and thereby also shifting the reflection from the corrector such that it was above the projector lens, therefore not creating the retro-reflection "ghosting." Does that sound right, John?
You pretty much nailed it, but to add to your response the ghosting can happen even when the angle of incidence to the screen is not zero. This is because there are curved surfaces on the primary lens and, even if the projector was offset, some of the retroreflected light could reflect some light back into the primary if the angle was just right. This is one of the reasons we promote our hybrid design above purely cylindrical lenses which are pretty much forced to retroreflect some light back into the primary.
 

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You pretty much nailed it, but to add to your response the ghosting can happen even when the angle of incidence to the screen is not zero. This is because there are curved surfaces on the primary lens and, even if the projector was offset, some of the retroreflected light could reflect some light back into the primary if the angle was just right. This is one of the reasons we promote our hybrid design above purely cylindrical lenses which are pretty much forced to retroreflect some light back into the primary.

I think there could be some wisdom in the projector mount height being somewhat adjustable if the ceiling height permits. ;)
 
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