Twenty inches changes more than the diagonal
Moving from 100 to 120 inches increases image area substantially, not just edge length. That can create a more immersive picture, but it also spreads the projector's light over more surface and changes where the UST projector must sit.
Measure the wall first
A 16:9 100-inch image is roughly 87 inches wide; a 120-inch image is roughly 105 inches wide. Add the frame, then check side clearance, speakers, outlets and the vertical space above the cabinet. Always use the exact manufacturer's dimensions before drilling.
UST cabinet depth can become the hidden constraint
As image size increases, many UST projectors need to sit farther from the wall. That can pull the cabinet into the room. A screen size that fits the wall can still be impractical if the projector's required placement creates an awkward furniture layout.
Brightness and gain become more important at 120 inches
The projector is illuminating a larger area, so perceived brightness can drop. With a 0.6-gain ALR surface, check your projector's output, room-light level and preferred picture mode before assuming the larger option will look equally punchy.
Use viewing distance as a comfort check, not a rigid rule
Some viewers love a cinema-like field of view; others find it tiring. Tape the projected corners on the wall and live with the intended size for a few evenings before buying the frame.
Want to judge the material in your own room?
The sample is intended to let you inspect the Black Series material before committing to a full screen. Check current stock, price and refund terms on the merchant page.
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