Anamorphic lenses & panamorph?

kenshingintoki

Distinguished Member
Hey guys, can someone explain to me how anamorphic lenses work? For example, If I wanted to use one on my Epson and what advantages I'd get? I've heard you get an insane brightness boost? like 30%?
 

Gordon @ Convergent AV

Distinguished Member
AVForums Sponsor
Depending on the lens you may get about 25% increase in light output. However, to avoid optical distortion you normally have to have the projector near the end of it's throw ratio (ie further away from the screen) which makes image dimmer than if it was nearer the screen. Also, using any anamorphic lens will require scaling of the image and any scaling, even Lumagens scaling that is best in class, will slightly soften the picture. I'd recommend you only want to use an anamorphic lens if you have your projector at the back of the room on a long throw or in a projection booth and you have a large screen that really need the light boost you may get.
 

kenshingintoki

Distinguished Member
Depending on the lens you may get about 25% increase in light output. However, to avoid optical distortion you normally have to have the projector near the end of it's throw ratio (ie further away from the screen) which makes image dimmer than if it was nearer the screen. Also, using any anamorphic lens will require scaling of the image and any scaling, even Lumagens scaling that is best in class, will slightly soften the picture. I'd recommend you only want to use an anamorphic lens if you have your projector at the back of the room on a long throw or in a projection booth and you have a large screen that really need the light boost you may get.
Thanks Gordon. Damn so its not plug and play in terms of lenses and will requirer an external video processor? :(

I'm 6.5M away from my screen at 165'' so I tick the boxes for a few of the criteria I think.
 

ask4me2

Active Member
The extra light output is only happening when using the entire 16:9 area in the projector light engine on source material like 2.35:1 Cinemascope movies that otherwise will have black bars.

The A-lens have its own transmission TStop value as any lens so projecting a 16:9 stretched 2.35:1 source that in theory will get 33% extra light output will often be reduced down to 25% or even lower.

Many projectors and some BD players have anamorphic stretch or squeeze built-in, and some of what you lose in sharpness by scaling and not getting 1:1 pixel mapped picture on the screen, you gain by having the entire projector pixel resolution showing the active picture and not wasted on the black bars.

One other thing, A-lenses often adds pincushion or barrel distortion depending on the construction and throw. The 1.33x horizontal stretch A-lenses from Isco often needs a curved screen, to get the same picture height in the middle as on each side.
 
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kenshingintoki

Distinguished Member
The extra light output is only happening when using the entire 16:9 area in the projector light engine on source material like 2.35:1 Cinemascope movies that otherwise will have black bars.

The A-lens have its own transmission TStop value as any lens so projecting a 16:9 stretched 2.35:1 source that in theory will get 33% extra light output will often be reduced down to 25% or even lower.

Many projectors and some BD players have anamorphic stretch or squeeze built-in, and some of what you lose in sharpness by scaling and not getting 1:1 pixel mapped picture on the screen, you gain by having the entire projector pixel resolution showing the active picture and not wasted on the black bars.

One other thing, A-lenses often adds pincushion or barrel distortion depending on the construction and throw. The 1.33x horizontal stretch A-lenses from Isco often needs a curved screen, to get the same picture height in the middle as on each side.
As Ask4me2 says it snot so simple. The Panamorph lenses that are the most popular now really need 1.6 times screen width throw but i'd suggest you really want to look at 1.8 x... and you are below 1.6...so not ideal


Thank you guys. I'll leave the lenses alone. Don't look worth the trouble lol.
 

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