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If I get a curved screen what are the pros and cons? Do I need a different projector setup? I have a benq 1070 and will be projecting on either a 135 16:9 or a 150 16:9, my other question is who besides innovative screens make a black screen? The problem I'm having is i dont see the black diamond in a 150 or 135 size at 16:9 ratio
 

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Curved screens do help with keeping the image in focus right to the outside edges however they also reduce the viewing angle so if you have a wide seating area and you sit close to the screen the image may not be as good for those who sit on the sides.
my other question is who besides innovative screens make a black screen?
Sorry, I don't follow you on this question?
 

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Curved screens do help with keeping the image in focus right to the outside edges however they also reduce the viewing angle so if you have a wide seating area and you sit close to the screen the image may not be as good for those who sit on the sides.

Sorry, I don't follow you on this question?
Innovative screen only makes the black diamond in max size of 120 for 16:9 ratio.. so I would like to know who else makes a black screen
 

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Curved screens do help with keeping the image in focus right to the outside edges however they also reduce the viewing angle so if you have a wide seating area and you sit close to the screen the image may not be as good for those who sit on the sides.


Sorry, I don't follow you on this question?
I thought that they were mainly for people with Anamorphic lenses to fix pincushion or bow tie shaped distortion...:dontknow:
 

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if you think about it, when you shine a projector at a flat surface the middle of the image has less distance to travel than the outsides (take a measuring tape from the lens to see for yourself). For screens that are 2:37:1 (wide screens) this is even more prominent. Now dont get me wrong, the lens on the projector its self does compensate for this to a certain degree but it can still be noticeable.
 

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if you think about it, when you shine a projector at a flat surface the middle of the image has less distance to travel than the outsides (take a measuring tape from the lens to see for yourself). For screens that are 2:37:1 (wide screens) this is even more prominent. Now dont get me wrong, the lens on the projector its self does compensate for this to a certain degree but it can still be noticeable.
But that's not how optics works. A conventional lens is flat-field, designed to project a flat image plane on a flat target screen. This would be true of all projection lenses, including film systems.

Kodak once produced a series of "curved field" projection lenses that were designed to project the natural curve of a piece of film in an open slide mount in focus on a flat screen. The focus plane was variable, edge to edge. The sort of worked, but only for curved cardboard mounted slides. Otherwise, the standard for image projection was (is) flat field. In the film days this meant optimal image sharpness occurred when the film was flat, in a glass mount, or was a non-curling stock like 35mm release prints. 35mm anamorphic prints were projected with flat field lenses followed by the anamorphic cylindrical lenses, but held sharp focus over the full 2.39 width.

Obviously an image element in a video projector is a flat plane.

Flat-field lenses are easy, and pretty much nothing special. For home theater projectors the trade-off is the amount of light a lens will pass (directly related to its F number: the ratio of the diameter to focal length) and cost. Low F-number lenses pass more light but get beastly expensive because of their large diameter. With low F numbers comes very critical focus (depth of field), so it's an advantage to gain light through another means. As an example, the Epson 9350 has a lens with F numbers from 2.3 to 3.6 (the diameter stays constant, the focal length changes as you zoom). That may be enough depth of field to hold focus on a curved screen, but it will depend on several factors.

Simply put, a projector is designed to project a flat image plane on a flat screen. If focused at the center, a curved screen will tend to push out of focus at the edges, depending on lens F number, and depth of curve. It's easy enough to verify with a focus test pattern. The last 9350 I set up was tack-sharp edge to edge on a flat screen.
 
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