The system gets installed in daylight and can only be aimed after dark. Those are two different visits.

Book the night visit, because the daytime aim is provisional

This is the whole page in one instruction. Beam spread, glare, shadow patterns and spill cannot be accurately evaluated in daylight, so whatever direction a fixture is pointed at three in the afternoon is a guess that happens to be pointing somewhere. The night visit is when angle and orientation are refined, beam spread is adjusted to eliminate hot spots and dark gaps, intensity is balanced so no area feels overlit or flat, and spill and glare are corrected. Treat it as a scheduled stage of the installation rather than a courtesy call, and if you are hiring, ask directly whether it is included. A quote that does not mention it usually does not contain it.

Glare makes you see less, which is the opposite of what people assume

Worth understanding because it settles the most common argument in outdoor lighting, which is somebody wanting brighter fixtures for security. Dark-sky association material puts it plainly: glare is the direct view of a light source against a dark background, and it overloads the eyes and actually reduces the ability to see in a generally dark environment, which can cause accidents. The eye adapts to the brightest thing in view, so a visible bright fixture makes everything around it read as black. The cause is also named precisely, and it is geometry rather than wattage: poorly shielded lights aimed at least partially horizontally rather than down at the surface. A brighter fixture aimed the same way makes the problem worse, not better.

Go and stand somewhere else, because you cannot see spill from inside your own yard

The cheapest and least performed test in the trade. Three separate sources give the same instruction in slightly different words: after installation, view the lighting from the neighbor’s perspective or from the street and adjust anything producing unwanted glare; take photographs from neighbor vantage points where possible and with permission, recording which fixtures create the most spill; and simply check fixtures from all viewing angles. The reason it gets skipped is that an installer naturally evaluates a system from inside the property looking outward, which is the one position from which light trespass is structurally invisible. Walk the street. Walk the sidewalk. If you can, stand where the neighbor stands.

Know which piece of shielding hardware solves which problem

These are not interchangeable and buying the wrong one wastes a trip. Glare shields or shrouds attach to the top or side of a fixture and focus the light in a chosen direction, which is the general-purpose answer. Full cut-off eliminates any light above the horizontal plane, which is the strictest option and what dark-sky ordinances tend to want. Half cut-off permits some light above horizontal and is a deliberate compromise where a little upward spill is wanted. Louvers and baffles are angled or parallel blades inside the fixture, described memorably as tiny venetian blinds, and they block light from specific angles without cutting everything above a plane. Diffusers and frosted covers soften light rather than redirecting it, so they reduce harshness but do not fix aim.

Uplights at thirty to forty-five degrees, path lights low and tilted down

Two starting figures worth having in mind before the night visit, since they get you close enough that the adjustment is refinement rather than discovery. Uplights angled at roughly thirty to forty-five degrees graze a tree or a wall without carrying on into a window, whereas something closer to vertical throws light past the target into the sky and into upstairs rooms. Path lights want to be kept low and angled slightly downward so they illuminate the walking surface rather than presenting a bright source at eye level, which is the glare problem in miniature and the reason a path lit by too-tall fixtures is harder to walk than an unlit one.

Warmer and dimmer reads better, and the number is 3000K or lower

Two related choices that people get backwards from a showroom. On color, guidance is to use 3000 Kelvin or lower to reduce blue light and sky glow, and warmer light also flatters planting and masonry in a way cooler light does not. On output, the advice is blunt: brighter is rarely better in residential settings, softer light looks more natural, and low-lumen LEDs suit paths and accents. Both of those are easier to get right at specification than to fix afterward, since a fixture that is too bright can sometimes be shielded or lowered but a fixture that is the wrong color temperature has to be replaced, and mixing color temperatures across one property is visible immediately.

Check the local rules, because some of them are measurable

Outdoor lighting regulation is entirely local and more common than people expect. Mono County in California prohibits light trespass, moving lights, changing-intensity lights and glare. Orange County in Florida prohibits glare, obtrusive light, light trespass and visual nuisance. More significantly, some municipalities set maximum foot-candle levels at the property line, which turns a matter of neighborly judgment into a measurable standard somebody can hold a meter to. HOA rules vary independently of any of that. One phone call before design is cheaper than an adjustment after a complaint, and if a foot-candle limit applies it changes fixture selection rather than just aim.

And in some places the neighbors are not people

Worth knowing because it is a genuine legal constraint that surprises everybody. In Florida sea turtle nesting areas the Florida Fish and Wildlife Conservation Commission sets lighting guidelines, because artificial light disorients turtles and disrupts nesting and hatching. That is a real restriction on coastal properties with real teeth, and unlike a neighbor, the affected party cannot complain. Coastal and environmentally sensitive locations generally are worth checking specifically rather than assuming residential rules apply, and where spill onto a neighbor is the issue instead, the escalation order is to angle away, add shields and lower output first, with landscape screening, louvered window coverings or evergreen planting as the longer term answer for both parties.