Projection LabBMT / Preliminary projection design
Get the image on the wall.
Before the ceiling closes.
Solve screen geometry, throw distance, lens range, shift, and usable brightness in one deliberately practical workspace.
SELECTED LENS THROW RANGE1.44–2.32: 1
Active projector + lensEpson EB-PU1008B + ELPLM088,500 lm · 1.44–2.32:1 · WUXGA
02
Verify the geometry
Throw + optical axis
Geometry passes
LENS CL · CENTER
SHIFT ENVELOPE
16:9 IMAGE180″ DIAGONAL13.1 FT W × 7.4 FT H
18.8–30.3 ft lens-to-screen
Calculated distance range18.8–30.3 ftImage width × lens throw range
Lens center envelope1.7–11.6 ft AFFSelected: 6.7 ft
Horizontal envelope±3.9 ftSelected: 0.0 ft
Throw position45% across range1.84:1 required
Rear clearance line27.1 ft from screenRear face at 26.1 ft
Projector body + service assumptions
03 / Light budget
Brightness that survives
the actual room.
Manufacturer lumens are the beginning of the conversation, not the end. Apply system loss, screen gain, and ambient-light intent here.
Display luminance
Delivered light budget: 6,375 lumens
Classroom / meeting room. Above the 50 fL preliminary target for typical conference.
BRIGHTNESS MARGIN AVAILABLE
Required projector output4900 lm
Before the 25% loss allowance, this design needs roughly 6500 rated lumens.
Screen-brightness benchmark66 fL delivered
Dark room14–22 fL
Controlled22–40 fL
Classroom40–70 fL
Bright ambient70–100+ fL
66Calculated from 6,375 delivered lumens, 96 ft² of image area, and 1.0 screen gain.
Design notes
Useful math.
Not a stamped drawing.
Throw is lens-to-screen
Use optical distance, not room length. Account for wall build-outs, lens position within the chassis, and mounting hardware.
Shift is not magic
Published shift limits can shrink when horizontal and vertical shift are combined. Confirm the exact lens and manufacturer shift chart.
Light needs margin
Real systems lose output to calibration, aging, optics, and ambient light. This tool exposes the allowance instead of pretending physics is optional.
BMT Projection Lab · Preliminary Design
Epson EB-PU1008B + ELPLM08 · ELPLM08
Image180″ · 16:913.07 ft W × 7.35 ft H
Lens-to-screen24.00 ftAllowable 18.83–30.33 ft
Required throw1.84:1Within published range
Lens center6.68 ft AFFEnvelope 1.75–11.60 ft
Screen luminance66.3 fL / 227 nits6375 usable lm · gain 1.0
Rear service line27.15 ftMeasured from screen face
Assumptions
25% calibration, optical, and aging loss applied. Throw distances are measured from the projector lens reference plane to the screen image plane.
Preliminary design only. Verify lens compatibility, combined-axis shift limits, chassis dimensions, installation orientation, and current manufacturer specifications before construction.