I operate an outboard boat early mornings when it is as dark as it gets at night to duck hunt. I have two 20,000 Lumen LED light bars on the front of my boat and they are great for finding blinds and the like after making a run but they are worthless for navigating. Any light at all ruins your night vision which is pretty good for most folks if they will allow themselves to get used to it and trust it. Headlamps on a car allow the driver to see about 150 feet in front of them with low beams (about 200 feet on high). They are shining on a surface that is normally not very reflective.....when the street is wet that distance is FAR less.....and they're are less reflective surfaces for the lights to shine on adjacent to the road....trees, grass, shoulders, white lines etc. None of the latter exists on a lake and are of little use even on a river of any size....so the lights are just shining into a void with nothing for them to illuminate....with the added nuisance of the light shining on a highly reflective surface.....between the reflection and the lack of objects being illuminated on the peripherary of the light there is simply no frame of reference and you can only see about 30-40 feet in front of the boat. Car head lamps are typically around 1200 lumens. I have 2 - 20,000 on my boat and I do not use them except when I know I am on top of where I am headed because the environment that those lights are cast into is so reflective that you can't see much of anything......its closer to staring into oncoming lights than it is to driving a car at night. I use the lights to spot blinds and openings in grass that I know is there but cant find but only when I know I am 30 feet or so away....and to set decoys....but they are useless for navigating as is almost all light on a boat at night....far safer to run at a safe speed with the least amount of light on as required.....in my epxerience
