Enable Prepar3D HDR and Dynamic Lighting, tune bloom and brightness for realistic nights, and fix washed-out cockpits, dark runways and low FPS.
To enable HDR and night lighting in Prepar3D, open the simulator's graphics or display options, turn on HDR Lighting, then enable Dynamic Lighting if your version and add-ons support it. Keep bloom modest, adjust brightness and saturation in small steps, and test at night in a default aircraft before changing add-on scenery.
What do HDR and Dynamic Lighting change?
HDR Lighting controls Prepar3D's internal exposure, colour and bloom processing. It is not the same as enabling HDR10 on a monitor or turning on Windows HDR.
Dynamic Lighting allows compatible landing lights, apron floodlights and other sources to illuminate nearby surfaces. Night textures, glowing light points and cockpit instrument lighting remain separate systems, so HDR alone will not make a non-dynamic scenery light cast light onto the ground.
| Setting | What it controls | Practical starting point |
|---|---|---|
| HDR Lighting | Tone mapping and overall night-time rendering | Enable it, then tune the associated sliders |
| Brightness | Overall exposure rather than individual lamp strength | Keep black areas dark without losing all shadow detail |
| Bloom | Glow around bright lights | Use a restrained amount; excessive bloom hides runway detail |
| Saturation | Colour intensity | Begin near neutral and avoid unnaturally vivid taxiway lights |
| Dynamic Lighting | Light cast onto aircraft, buildings and the ground | Enable for compatible aircraft and airports |
| Shadows | Objects and terrain affected by light sources | Use selectively because night-time airport shadows can be expensive |
How do I enable Prepar3D HDR and night lighting?
The labels and layout differ between Prepar3D generations, but the controls are normally on the Graphics or Display options page under a lighting section.
- Establish a clean baseline. Load a default aircraft at a default airport and temporarily disable post-processing presets. Set the scenario's local time after sunset, using clear weather so clouds do not confuse the comparison.
- Open the graphics options. Enter Prepar3D's Options screen and locate the Display, Graphics or Lighting controls provided by your installed version.
- Enable HDR Lighting. Turn on the HDR option where it is offered. Do not add an undocumented configuration entry if your version does not display the setting.
- Enable Dynamic Lighting. Also enable an option such as landing lights illuminating the ground if your version presents one. Older scenery effects may remain simple glowing points because they were not authored as dynamic lights.
- Set conservative HDR values. Start with neutral brightness and saturation, then keep bloom low enough that runway edge lights remain distinct rather than merging into a luminous strip.
- Apply and test the changes. Compare the external view, instrument panel, runway and an unlit area. Restart Prepar3D if a renderer or lighting change does not appear immediately.
- Repeat under different conditions. Check a moonlit night, a dark rural location and a busy airport. One scene cannot reveal every exposure problem.
Night lighting itself has no universal master switch: the simulation clock activates night textures and airport effects, while aircraft switches and dimmers control landing, taxi, panel and flood lighting. Our recommended Prepar3D graphics settings and trade-offs provide a broader baseline for the surrounding options.
How should HDR be tuned for realistic night flying?
A realistic setting preserves darkness rather than making every object visible. HDR brightness changes the whole image, so raising it to fix one dim cockpit will usually make airport lighting, clouds and the horizon look washed out.
- Adjust cockpit lights first: use the aircraft's instrument, panel and flood-light dimmers before changing global HDR brightness.
- Keep bloom controlled: runway and taxiway lights should have defined centres. Large coloured halos usually mean bloom or another post-processing effect is too strong.
- Protect black levels: an unlit rural area should be genuinely dark, while illuminated instruments should remain readable.
- Use restrained saturation: excessive saturation makes green taxiway centreline lights and blue edge lights look fluorescent.
- Compare like with like: moon phase, cloud cover, visibility and atmosphere settings all affect perceived brightness. Save one reference scenario for repeatable adjustments.
Monitor black level and gamma matter as much as the simulator sliders. Because Prepar3D's HDR Lighting is an internal rendering effect, enabling operating-system HDR on an unsuitable display can produce grey blacks or altered brightness rather than improving the image.
Why are my Prepar3D night lights too dark or too bright?
Why do lights glow but not illuminate the ground?
This usually means the effect is a legacy light point rather than a dynamic light source. Confirm Dynamic Lighting is enabled, test a default aircraft and airport, and then check that the aircraft or scenery was built for your Prepar3D generation.
If the problem occurs at only one add-on airport, changing global HDR settings is the wrong fix. That points instead to missing effects, incompatible scenery, material design or scenery-library ordering.
Why is the cockpit washed out at night?
Excessive bloom, high global brightness or a second post-processing layer commonly causes a washed-out cockpit. Return Prepar3D's values to a conservative baseline and disable ReShade temporarily; if you want to use both systems, follow our ReShade configuration guidance for Prepar3D and avoid applying exposure or bloom twice.
Why are the instruments readable but the runway is black?
Check the aircraft's landing and taxi-light switches, confirm that the relevant ground-illumination or Dynamic Lighting option is enabled, and test the same runway with a default aircraft. If another aircraft illuminates it correctly, the original aircraft's light effects or compatibility are responsible rather than HDR.
How much performance does Dynamic Lighting cost?
Dynamic Lighting is normally more demanding than HDR tone mapping, particularly at detailed airports containing many overlapping light sources. If frame rate falls only at night, reduce dynamic-light use, shadow complexity and reflections before sacrificing texture quality.
For a systematic approach, our Prepar3D performance-tuning advice explains which settings to lower first. Change one option at a time so you can identify whether dynamic lights, shadows, clouds or scenery complexity caused the loss.
What if HDR settings are missing or will not save?
A missing option may simply mean that the installed Prepar3D version or rendering mode does not expose it. If settings are shown but repeatedly revert, close the simulator normally, remove any external utility that overwrites graphics settings, and check that Prepar3D.cfg has not been made read-only.
Corrupted generated settings can also cause unusual exposure, black effects or controls that refuse to persist. Use our safe Prepar3D.cfg reset procedure rather than copying undocumented tweaks from another version.
For lighting artefacts that appeared after a graphics change or add-on installation, close Prepar3D and rename the generated shader-cache folder at %LOCALAPPDATA%\Lockheed Martin\Prepar3D vX\Shaders, replacing vX with your installed version. Prepar3D rebuilds that cache on its next launch; the first load may therefore take longer.