Golf Simulator Projectors: Throw Ratio Does the Choosing

A golf simulator projector gets bought last, after the launch monitor and the enclosure have eaten the budget, and it is the one component the room itself can refuse. Throw ratio is geometry, and geometry does not negotiate with brightness, resolution or money: the wrong number means a returned box. Run the throw math first and every other spec turns into a preference, which is why projector geometry belongs early in the sequence of simulator decisions.

Throw ratio is the spec that vetoes the room

Throw ratio is one number: the distance from the lens to the screen divided by the width of the image it makes there. A 0.8 unit standing 8 feet back paints a 10 foot wide picture. Move the same projector to 12 feet and it paints 15 feet of picture, which spills off the fabric and onto the enclosure padding, the ceiling and the wall behind. That one ratio decides whether a projector can live in your room at all, and nothing else on the spec sheet can overrule it.

The veto exists because a simulator bay asks the lens to do two contradictory things at once. It has to fill a screen 10 to 14 feet wide, and it has to do that from a position outside the swing arc, outside the ball's rebound path, and out of the golfer's own shadow. BenQ puts the usable band for golf at 0.5 to 1.1, with 0.69 to 0.89 as the practical balance for a standard home room. Anything above 1.1 wants more depth behind the tee than a house normally has.

The formula, and how to run it backwards

The formula every manufacturer prints reads throw ratio equals throw distance divided by image width, and the version BenQ publishes is the same one. It is useful for checking a projector you already own and almost useless for shopping, because you are not trying to discover a ratio. You are trying to discover which ratios your room will tolerate. Rearranged for that job, the same arithmetic gives two more useful forms: throw distance equals throw ratio multiplied by image width, and required throw ratio equals available distance divided by screen width.

Run the second one first. Measure from the screen face to the point on the target line where a projector could hang safely, divide by the finished screen width, and the answer is the largest throw ratio you are allowed to buy. A bay with 9 feet of safe mounting distance and a 12 foot screen is shopping at 0.75 and below. That is a filter rather than a preference, and it removes most of the projector market in a single line of arithmetic before brightness, resolution or brand ever enters the conversation.

There is a correction to that formula almost nobody in this category prints. A 16:9 projector filling a squarer 4:3 or 1:1 impact screen is not using its full image width, so the width-based version gives the wrong distance. BenQ's own guidance handles it off image height instead: throw ratio equals throw distance multiplied by 0.5625, divided by image height, for a 16:9 native unit. A 16:10 native unit uses 0.6277 in place of 0.5625. Calculate off width, then mask down to a square screen, and the projector ends up mounted a foot or more from where it belongs.

Worked examples for 10, 12 and 14 foot screens

Three rooms at one ratio, so the arithmetic is visible rather than described. On a 10 foot screen a 0.8 unit mounts 8.0 feet from the fabric. On a 12 foot screen the same unit mounts 9.6 feet out. On a 14 foot screen it mounts 11.2 feet out, and BenQ's own worked example for a 14 foot by 7.9 foot image lands on the same 11.2 feet and puts the lens 2 to 3 feet behind the hitting area, which is roughly where a ceiling plate wants to be anyway.

Zoom range moves those answers more than people expect. The BenQ AK700ST is quoted at 0.69 to 0.83, so on a 12 foot screen it can sit anywhere between 8.3 feet and 10.0 feet from the screen, and a bay built around that upper figure wants about 13 feet of depth once the mount body and the clearance behind it are counted. A 0.496 lens like the one in Optoma's ZH451ST fills that same 12 foot screen from 5.95 feet, close enough to the fabric that a golfer never crosses the beam.

Read down the 1.5 column and the argument finishes itself. A standard throw living room projector needs 18 feet of clear distance to fill a 12 foot screen, which is behind the golfer, behind the launch monitor and usually behind the wall. The 0.5 and 0.8 columns are the only ones landing inside distances a house actually offers, and that is the entire reason a separate golf projector category exists.

Impact screens are squarer than a 16:9 image

A living room screen is 16:9. An impact screen is whatever shape the enclosure frame is, and most home bays land nearer 16:10, 4:3 or something custom, because the frame gets sized to catch a mishit rather than to match a broadcast standard. Feed a 16:9 projector to a squarer screen and one of two things happens: the image letterboxes with black bands top and bottom, or it overspills the fabric and paints the surround.

Overspill is the one to avoid. Light landing on enclosure padding bounces back into the screen and grays the image, and it is also a signal that the mount distance is wrong. The fix is to mask the projector's output down to the screen shape in software or with lens shift, and only then recalculate throw distance off image height using the height factor above. Doing those two steps in the other order is why so many projectors end up an awkward foot too far back.

Short throw, ultra short throw, and why standard throw fails

The category splits into three bands, and the boundaries matter more than the labels do. Standard throw sits above 1.0. Short throw runs from roughly 0.4 to 1.0. Ultra short throw sits below 0.4, usually near 0.25. Almost every projector sold into golf lives in the middle band, and the reason is the distance table above rather than any marketing decision.

Real numbers, taken from manufacturer pages rather than retail listings. BenQ's AH500ST, LK830ST and LH860ST are all 0.5. The AK700ST, AH700ST and AH30ST run 0.69 to 0.83. The LK936ST is 0.81 to 0.89. Optoma's ZH451ST pairs a 0.496 throw ratio with 4,200 ISO lumens and a 30,000 hour laser, and the cheaper GT2400HDR uses the same 0.496 lens at 4,200 ISO lumens in 1080p. Those ratios between them cover nearly every sensible home bay from 8 to 16 feet of screen.

Every one of these calculations starts from the finished width of a taut impact screen, not the enclosure's outside dimension. The gap between the two is usually 4 to 8 inches per side once the fabric wraps and tensions around the frame, and at a 0.8 ratio that difference moves the correct mount point by more than half a foot. Measure the fabric that will take the ball, then shop the lens against that number.

What a zoom range actually buys you

A quoted range like 0.69 to 0.83 is an optical zoom, and it is the most useful tolerance on the whole spec sheet. On a 12 foot screen that range is a mounting window running from 8.3 feet to 10.0 feet, so a ceiling joist that lands 9 inches off the ideal point costs nothing at all. A fixed 0.5 lens has no window: it fills a 12 foot screen from 6.0 feet and from nowhere else, which means the mount has to be built to the projector rather than the other way round.

Optical zoom does not throw pixels away, which is the difference between it and digital image shrink. Two cautions go with it. A zoom lens is at its sharpest through the middle of its range rather than pinned at either extreme, and using zoom to rescue a badly placed mount usually means the lens is also off the target line, which no amount of zoom corrects. Pick the mount point from the arithmetic, then spend the zoom on the last few inches.

Where ultra short throw actually earns its place

Ultra short throw gets recommended for low rooms by guides that never print a single UST throw number, so here is one. Optoma's ZH430UST is 0.25 to 1, 4,000 ISO lumens and 1080p, and its published throw distance range is 1.5 to 2.4 feet. Divide that range by the ratio and the widest image it can make is 9.6 feet. A 12 foot impact screen is not a stretch for that projector, it is outside the lens entirely, and no setting recovers it.

Even inside its range a 0.25 lens sitting 2 feet from the fabric is in the ball's rebound path unless it is sunk into a floor box, and the alignment tolerance collapses to inches: move it 1 inch and the image grows 4 inches. UST is the answer after a room has run out of better answers. Rooms under 8 feet of ceiling change the question from which projector to which compromise, because a ceiling mount has nowhere safe left to hang and the lens has to come down to the floor.

Lumens for a dark basement and a lit garage

Brightness is the spec most people shop first, and it is the one with the most slack in it, because the room does at least half the work. BenQ's guidance splits the answer rather than giving one floor: 3,000 ANSI lumens is a sensible starting point for a smaller impact screen, and once the screen passes 10 feet wide the recommendation moves to a 4,000 lumen or brighter laser. The split matters because lumens spread across area, and area grows faster than width.

The same projector is a different projector on a bigger screen. Going from a 10 foot wide image to a 14 foot wide image at the same shape nearly doubles the lit area, so a 4,000 lumen unit that looked bright on the small screen delivers roughly half the brightness per square foot on the large one. Ambient light then decides the rest. A blacked out basement bay makes 3,000 lumens look generous. A garage with one uncovered window makes 4,000 look thin at four in the afternoon.

The cheapest brightness upgrade is not a projector. Matte black or dark gray fabric on the surround and on the side walls inside the light path kills the reflected bounce that gray-washes an image, and it costs a fraction of the next 1,000 lumens. Light source type matters for a different reason. A laser holds its output across 20,000 hours on BenQ's AK700ST and 30,000 hours on Optoma's ZH451ST, while a lamp fades measurably inside its first 1,000 hours and then has to be bought again.

ISO lumens, ANSI lumens, and the 20 percent nobody mentions

Two measurement standards are in circulation, and they get printed in the same column of every comparison table in this category. ANSI IT7.228 and ISO 21118 call for essentially the same nine-point brightness measurement, so a 4,000 ISO figure and a 4,000 ANSI figure are comparable as readings. What differs is the promise attached to the number. ISO 21118 was written so a brightness claim cannot rest on one flattering sample: it asks for a figure that describes average production, and it still allows an individual unit to measure as much as 20 percent under the number on the box. ProjectorCentral's golf projector price list is the only place in this field that labels which standard each figure was taken under.

That slack shows up inside a single model. Optoma publishes 4,200 ISO lumens for the ZH451ST on its own product page, while ProjectorCentral's listing for the same projector reads 4,000 ISO lumens. Neither figure is invented and neither is worth a decision on its own. The working rule is to read the standard sitting next to the number before comparing anything, then to treat a gap under about 10 percent between two brands as noise, because the tolerance underneath the spec is wider than the gap.

Ceiling, floor, or behind the golfer

Four mount positions get used in home bays and they are not equal. Overhead is the default, hung upside down from the ceiling, and BenQ's own FAQ says simulator setups usually go that way. A floor enclosure sits in front of the hitting area and carries a real strike risk. A cart or side mount beside the mat carries the highest shadow risk, because a position that suits one handedness rarely suits the other. A tripod is a temporary answer rather than an install, and it leaves an unsecured stand standing in a room where a ball is traveling at a wall.

The target BenQ gives for the good case is precise enough to build from: on the target line, about 7 to 8 feet from the screen so balls do not bounce back into it, and no more than 3 to 4 feet behind the player so the swing never crosses the beam. On a 12 foot screen that window works out to a 0.58 to 0.67 throw ratio, which is exactly why the 0.5 units exist. On a 10 foot screen the same window asks for 0.7 to 0.8, which is the middle of the short throw band.

The shadow problem, worked out

Shadow advice in this field usually stops at avoid it. The geometry is more useful than the advice. At a 0.8 ratio on a 12 foot screen the lens sits 9.6 feet from the fabric, and BenQ's own placement puts the tee 2 to 3 feet in front of that, which means the golfer stands inside the beam rather than behind it. Two to three feet out from the lens the cone has only opened to about 2.5 to 3.75 feet across, so a player at address is not clipping a corner of the image. The head and the top of the backswing sit in most of the beam's width unless the lens hangs high enough to clear them.

Height is the variable that fixes it. A driver at the top of a tall golfer's backswing reaches past 8 feet, so a lens on the target line at 8 feet 6 inches or higher clears the club and throws its shadow down onto the mat where nobody is looking. The asymmetry nobody quantifies is the side mount: a cart positioned to clear a right handed swing sits directly in a left hander's line, so any bay used by both hands has to be centered. The test costs nothing. Stand at address, take the club to the top, and watch the screen before a single mount hole is drilled.

Lens shift beats keystone, every time

Two controls move an image that is not squarely aimed, and they are not equivalent. Lens shift is optical: it slides the whole light path up, down or sideways without touching a pixel, so a shifted image is as sharp and as bright as an unshifted one. Keystone correction is digital: it redraws the image smaller inside the panel to fake a square, throwing away resolution and brightness on the way through.

In a simulator bay the difference turns up on ball flight lines, which stair-step into jagged diagonals once the panel has been resampled. Keep digital correction under about 5 to 10 degrees and treat anything past that as evidence the mount is in the wrong place. The cheapest correction is still a mount plate that can be shimmed level, aimed straight down the target line and then left alone for the next five years.

Ball strike, rebound, and what holds the unit up

The projector has to sit outside two paths, not one. The ball's flight to the screen is the obvious one. The rebound off a loose impact screen is the path that breaks hardware, and it leaves at an angle that depends on how well the fabric is tensioned. Three pieces of hardware answer the problem: a ceiling plate with a drop pole, a frame arm that bolts to the enclosure's top rail, and a floor box at the bay's front edge. GolfBays sells the frame arm and protective case at $299.

That arm bolts to the enclosure's top rail, so a self-assembled enclosure frame has to specify that rail for the projector's weight before any tubing gets cut. These are not heavy machines: BenQ publishes 7.5 pounds for the AK700ST, so even with a plate and a drop pole the hanging load stays under about 15 pounds, which is nothing to a ceiling joist and quite a lot to a thin conduit crossbar. Cabling is the other install reality. In our own bays a passive HDMI run stays dependable to about 15 to 20 feet, and past 25 feet we specify an active or fiber cable, a distance a ceiling drop reaches faster than anyone expects once the run goes up the wall, across the joists and back down.

Resolution, refresh rate, and the input lag nobody quotes

Resolution is where the money goes and it deserves less argument than it gets. BenQ's position is that 1080p or WUXGA is acceptable and 4K is preferred, and the premium is real in one specific case: a golfer at the hitting position in front of a screen 12 feet or wider can resolve green contour and turf texture that a 1080p image smears together. On a 10 foot screen at normal hitting distance, most owners cannot pick the two apart in a blind look.

The spec nobody in this category publishes is the one that changes the answer. Input lag is the delay between the software drawing a frame and the projector showing it, and in a simulator it lands in the gap between the sound of the strike and the ball leaving the screen. Refresh rate sets the floor under that delay, so the two specs have to be read together. Every guide in this field argues 1080p against 4K on picture quality alone, and picture quality is only half of the trade.

What 4K actually costs you in latency

One projector makes the point without needing a second opinion. BenQ's published lag figures for the AK700ST read 33.4 ms at 4K 60Hz, 33.4 ms at 1080p 60Hz, 16.7 ms at 1080p 120Hz and 8.4 ms at 1080p 240Hz. Resolution is not what costs the time. Refresh rate is. Dropping the same unit from 4K 60Hz to 1080p 240Hz cuts the delay by about 75 percent, and the picture a golfer sees from address barely changes.

Optoma's numbers run the same way. The ZH451ST is 16.7 ms at 1080p60 and 8.4 ms at 1080p120 across a 24 to 120Hz vertical scan range, and the GT2400HDR matches it at 8.4 ms at 1080p120. For scale, 33 ms is about two frames of a 60Hz image, which is inside the window a golfer registers as a lag between contact and ball flight. Anyone whose bay doubles as a gaming screen, and anyone who feels the launch arriving late, should run 1080p at 120Hz or higher and put the 4K money into lumens instead.

What the projector costs, and what the install adds

Prices below are street and MSRP figures read on 21 August 2026, because neither BenQ nor Optoma publishes a list price on its own product pages. The useful band for a home bay runs from about $1,299 to $2,899, and the ladder is short because most of the projector market is either too long in the throw or too dim for a 12 foot screen. Epson's golf simulator listings bracket the wider range, from a $1,416 PowerLite L260F to a $6,349 PowerLite L790SE, and the top of that is a commercial number rather than a home one.

Two things fall out of that table. The $2,499 LK830ST and the $2,899 AK700ST carry the same 4,000 ANSI lumens and the same 4K panel, so the $400 between them buys nothing on the screen: it buys the AK700ST's 0.69 to 0.83 zoom window, where the LK830ST is locked at 0.5. That is a mounting decision, and a room with a joist in an awkward place is the only room that should pay it. At the other end, the $1,299 GT2400HDR gives up 4K and gives up nothing on throw ratio, brightness or input lag, which makes it the floor of the category rather than a compromise inside it.

The install line items nobody prices

The box is not the cost. A projector hanging in a finished bay carries a mount, an arm or plate, a cable run and often an electrician's hour. The frame arm and case GolfBays sells is $299. For the rest we budget $60 to $150 for a ceiling plate with an adjustable drop pole, $40 to $120 for an active or fiber HDMI cable long enough to make a ceiling drop, and $150 to $300 for a new outlet above the bay where there is not already power in the joists.

Add those up and a $1,599 projector becomes a $2,100 line by the time it hangs and lights. That is the number worth carrying into a build sheet, because at $1,299 to $2,899 for the units worth owning the projector is usually the third-biggest line item in a home simulator, behind the launch monitor and the enclosure. Budgeting the sticker alone is how a build ends up with a $2,899 projector balanced on a folding chair for its first six months.

The order to settle the decision in

Six steps, in this order, and the projector question closes in an evening. Run them out of sequence and you end up shopping brightness for a projector the room was never going to accept.

1. Measure the finished screen width, meaning the fabric face that takes the ball, not the enclosure's outside dimension.
2. Find the safe mount point: on the target line, 7 to 8 feet from the screen, above a raised club and outside the rebound path.
3. Divide that distance by the screen width. The answer is the highest throw ratio you are allowed to buy, and it is a filter rather than a preference.
4. Set the brightness floor from the room: 3,000 lumens for a dark bay under 10 feet of screen, 4,000 or brighter laser for anything wider or with daylight in it.
5. Pick resolution and refresh rate together, using published input lag figures rather than pixel count, and match them to how the bay actually gets used.
6. Price the mount, the arm, the cable and the outlet before the projector, then compare installed totals rather than stickers.

One shortcut skips most of that work. Several of the packages we rank ship with a short-throw projector already matched to the screen in the same box, which moves the throw math off the buyer and onto the vendor who chose both parts together.