I'm fairly serious about being seen in traffic. I ride a fair bit, and it's not a question of "if" but of "when" I get hit. Lighting might reduce that risk, though it's impossible to tell. If I get hit, I will know that the lights didn't help, but there is almost no occasion when I can know that they did help. A driver is not going to say, "I was just about to hit you, and then I saw your light."

I use my lights regardless of time of day.

For 15 months, I've been using a Cygolite Hypershot 350. I like it very much. I usually use it in blinking mode. I've been told it's too bright by cyclists behind me. Maybe it's also a problem for motorists, but that's another message I'm unlike to get. So this week, put it on steady mode, and I believe that reduces the output to less than 350 lumens. Even at the reduced output, it might use more battery energy since it's on 100% of the time I'm using it.

Do folks here have any suggestions for reaching a reasonable compromise? Maybe this is bright enough to catch attention without causing pain.

Maybe I should use a blinky taillight as a supplement, and at a lower intensity, of course.

One nice feature I noticed is that it indicates low battery when I turn it on. It blinks very rapidly for about a second. It did that last night on my commute, and I made it home before it gave out, so the warning comes on at a good time, not too late.

This light was $50 when I bought it, and now you can get it for $36, so I highly recommend it.

Why does my spelling checker think that "blinky" isn't a word?

Decades ago, Bicycling! magazine did a review of the (mediocre) lighting choices available for bikes that were then currently available. The one thing I remember from it was that under most conditions, reflective ankle bands were more effective than most of the lights tested at conveying to drivers that they're seeing a cyclist.

I've almost never ridden any of my bikes without a pair strapped to my ankles since then, regardless of what light I'm using.

I had to ride off of the road and onto the shoulder when I could see (in my helmet mirror) that a passing car wasn't pulling to the left to pass. He ended up knocking off my left pannier. He did come back to check on me, and during our conversation, he did mention that he did see my (dynamo) tail light. It's counter-intuitive, but it's not enough to be seen. (this was when no other traffic was in sight).
Having said that, you do want to be seen, and the question is how to do it and be seen in all conditions.

I agree that it is a problem.
Brightness is good when you are among other bright lights and need to be noticed.
In a place with no other lights, this same bright light will be overwhelming.

My own guess is that the best compromise is to use a light that is of moderate brightness, but covers a large area. There's a limit to how much area you can cover on a bike, of course.
A compromise might be to use lights mounted at different points on the bike. Back when I had a Niterider headlight, I made a bottle battery for it out of translucent water bottle. I included a couple of yellow LEDs, so they lit up the bottle when the headlight was on. This made the bike visible in all directions, at least to a degree.

In fact, I was just riding on the local MUP last night and mixing it up with some heavy traffic as the trail crossed a road. With all of the traffic and the sea of headlights and tail lights, the odds of not being seen by at least one motorist seemed rather high. I decided to be as safe as possible and cross on the pedestrian crosswalk.

Steve in Peoria

I also have a Hypershot 350 and typically use it in the bright 'blinky' mode - during the day when riding alone. The other six modes have significantly less output so I'll switch to one of those when riding with friends or at night. When riding around sunrise or sunset, though, I'm glad for all 350 lumens (and for the bright white blinker I have up front). When driving I've seen bikes just disappear in lighting conditions like that and will take all the help I can get.

I use those, the type that are very reflective. To be honest, I use them only when I'm wearing long pants.

For a while, I used a trouser band that had a battery powered light. Very nice idea, but it was not at all stretchy and was uncomfortable. You're right that making the ankle motion visible is a huge win. The problem with reflectivity is that it isn't reliable. It reflects at some angles, but you never know.

Back when bike lights were super crappy, Wonder™ (remember them) made a light for the leg. I once took a ride on an unlit country road, a very scary proposition back then. The drivers treated me very kindly. So with motion of legs, I believe you do not need much brightness.

There is a guy where who calls himself 10wheels or something like that, and he uses many, many lights at once. That is sure to be effective, but not convenient enough for me. As you said, there isn't much area on a bike, and that is a problem for helping a driver ORIENT to what and where the bike is. That's why I think two taillights having different blinking patterns might help. I used to do that. Now I think my bright and steady light coupled with a dim and blinking light might be a similarly good compromise.

To be honest, I'm in NYC, and the environment at night is pretty darned good. There are zero unlit streets, and drivers are used to cyclists. Also, speeds are not high.

I also have the Cygolite Hypershot 350. A pair of them. And I also use the lights each and every time I ride.

A very nice feature of the HS 350 is that it allows setting of the intensity and of the steady/flash/pulse pattern. With a pair of them it's all but impossible to not be seen and hit, and it's easy to set them appropriate to the "balance" of brightness vs visibility necessary on the roads I ride.

The compromise I'm comfortable with is: I'll use settings I deem appropriate ... and they don't hit me. IMO, any other compromise is more likely to result in me on the ground and (at my age) possibly hospitalized; that, I won't have.

Of course, I don't ride in groups so, other than the unlikely instance of another cyclist tucking-in close behind me, all I need to be concerned with is drivers. With how bright LED lighting is getting on motor vehicles, these days, it's not as though the HS 350 is vastly and intensely brighter than everything else on the road. (Can be, with the highest brightness setting; but it needn't be set to that, if the roads' lighting situations don't warrant.)

High-grade lighting; multiples; set to varying patterns/output.
Settings appropriate for the visibility conditions on the roads I ride (typically, smaller country lanes with lots of trees).
Hi-viz jacket.
Riding on the MUP or sidewalk if ever it's too risky/tight on a road, depending.

Works for me. Seemingly works for the motor vehicle drivers who give me a wider berth than they once did when I only used a single, less-bright, steady taillight. A pair of taillights on different steady/pulse/flash sequences seems to "do the trick."

JMO

noglider: In 2016 I was hit by an inattentive driver less than a mile from my house. I live in a rural area with little traffic. I had noticed that close passes had been increasing and had given it not much attention up to that point. After being sideswiped I was focused on how to prevent another situation like that. I had heard of daylight viability lights so I looked on the web. I saw the Dinotte lights and picked out there daylight only one. They have you check a box that states you will only use it in daylight. It is so bright that a close up look see behind the bicycle is uncomfortable to my eyes. When riding in traffic I can see cars in my mirror move to the left from quite a distance back. If your light has no visible effect to you on how traffic responds then I would find one that does. I also run a generator light set that is good for at night.

I came upon two women riding Portland's popular but narrow Skyline Blvd driving. I'd been on full alert for cyclists. This stretch of road was straight, uphill, wooded and in partial shade. It happened that the woman wearing a bright jersey was in front and completely hidden from me by the following rider in a dark jersey and a medium intensity blinking tail light. I never saw that following rider until I brushed her arm with my mirror.

She was unhurt, scared and very angry. Absolutely could not understand why she wasn't seen. I didn't say much. They continued on and after I started up, I looked carefully at the two riders. The woman with the bright jersey, again well up the road was easy to see. That blinking tail light? I had to look for it knowing exactly what I was looking for. The rest of her, her clothing and her black bike were near invisible in that partial light on a full sun day.

I wanted that woman to know how hard she as to see but I knew there was nothing I could say or do would accomplish anything except maybe put me in front of a judge. Reminder to me - in daylight, bright, solid color jerseys (that come far enough down in back) work. Lights far less so. (I don't even remember if the lead rider had a light. Didn't matter. She didn't need one.)

I started up that hill consciously looking for riders. That dark rider with her taillight was in full view.

Adjust the aim or flip it upside down to put the beam lower... the later puts the clip at more stress tho.
does anybody make & sell that backside tab/latch out of aluminum or of a different design to allow a direct 1/4 turn attachment?

My wife's Hotshot tail-light flashes in my face sometimes, but I found ratcheting it down one or two notches solved the problem. It is still highly visible.

It's certainly incumbent upon every individual to ensure the contrasting factors actually "light up" a person visually. As you say, certain clothing and certain lighting won't always do it.

Hard to underestimate the value of a high-grade, extremely-visible hi-viz jersey or jacket.
Hard to underestimate the added value of high-grade tail lighting.
Visuals and contrasts can differ greatly, depending on the background, tree canopy, amount of sunlight/shade (dappling).

About all that can be said is: individuals need to actually adjust their choices based on the specific roads they ride on. As many have pointed out, not all hi-viz is made equal (in regards to good visibility with specific light conditions). As you and others have pointed out, only having lights won't be a panacea.

If I thought I could cleanly mount a hi-viz flag, I'd probably also add that to the list of precautions. As someone who doesn't usually exceed 12mph at any time, for me there's nowhere to go. It's be seen or else. And the wider pass-bys (with a given combination) are a dead giveaway. As you found in your incident, the one rider failed to ensure visibility ... and nearly paid for it.

I don't drive much but I do a lot of night riding with groups. On brevets, riders will be stretched out ahead and behind.

Some riders simply disappear into the night, others can be seen from a quarter mile away or more.

In darkness, I find solid lights show up better than blinkies. That's controversial, I'm sure. Reflective vests really pop. Reflective ankle bands are great when visible but are often obscured. Taillights mounted on seat stays disappear when the road has a slight bend. Lights mounted on bags disappear because they're pointed any which way. Headlights that light up a patch of road are sometimes the last thing to disappear in the distance.

Flashing lights at night can increase the chances of being hit by motor vehicles. I only use a flashing light in the daytime. I have the brightest one that I could find. My light is bright enough that contrasting factors or florescent bright clothing are irrelevant. At night or in low light such as dark overcast and rainy or snowy weather I use my generator light.

You could go back to flash but reduce the size of the light with blackout tape.

She must have had really long arms that extended to the other lane, right? No way a cyclist would be overtaking another cyclist with inches to spare.

Good that we have a much better choice of lighting at lower cost than 20 years ago. Lets us build up a system for particular situations.

My environment is 30-45 mph posted, minimal street lighting.

I have a number of LED red lights but I can’t remember all the models and powers. The two brightest have a bright to dim cycle over about 3 seconds (surge?) that I prefer to blinking. It’s less annoying when I observe it.

I consider my rear-facing helmet-mount the most important. I only turn it on when I take the lane or am concerned about the situation behind me. In addition to saving power, reaching back and turning it on changes the visual scene which will help draw attention to my presence.

I then have a seat post and a light looking back on each pannier. I usually just use the seat post light on “surge” but use the pannier mounts for higher-risk situations or if the seat post battery might run out.

I wear reflective ankle bands at night but they are obscured to the rear by my panniers.

I commuted by motorcycle for decades. The only relevant comment I can make about daytime riding is that bright sunny days, everyone sees you. But overcast days, you should act like you are invisible. I felt that I was safer on a sunny day even if my lights were turned off than I was on an overcast day with my lights on.

But, sunny or not, if the car driver is looking at their texts instead of the rest of world, you will get hit no matter what you do.

I have no relevant comments on taillights that were not already mentioned above.

Maybe I’m an idiot, and I have been know to look into blinding lights to only curse and ask myself “why the *#&@ did you just do that you dumb@$$”…. But I don’t think I understand why a cyclist would complain about another cyclist light being too bright. Unless it’s a night group ride or you on a dedicated bike trail. I would think I would just avoid looking directly into someone else’s light for a bit would be acceptable as you realize they are doing it for their safety.

Perhaps I don’t ride in enough city traffic to understand.

I don't have any links handy, but for some interesting reading look up ship and aircraft camouflage in WWII before radar. The allies did a lot of experimenting because silhouetted against the sky, lighting made a ship/plane LESS visible. Putting lights on booms to light up the broadsides of entire ships was effective but impractical. "Yehudi" lights on the leading edges of aircraft wings proved far more practical and with proper dimming the planes could be made to virtually disappear as they attacked.

Now I'm not saying that all of us ride silhouetted against bright backgrounds, but the background obviously matters. I think the takeaway is to focus on what the viewer sees, thinks, and does. More lights aren't always the answer.

maybe those people were a fly or gnat in their previous life?

When they blink and the background is dark, it is very difficult to follow where the light is going to be so you don't look at it. And once you do your vision is full of green splotches making it unsafe for you to continue riding.

So I can understand not wanting to trade my safety for another's.

Some people have a reflex to turn towards the light. I don't know if it is natural or learned. I don't tend to look at taillights but I do look at headlights. I had to train myself very hard not to look at painful and annoying headlights. So that might be the thing at play for the cyclists behind me. One of them is my spouse. The other was a stranger on the bike path. If I'm going to ride with my spouse, I'm going to do my best not to annoy her.

I've had it happen on a quiet rural road.
It was after sunset, but not totally dark yet.
The oncoming bike had a very bright light aimed high enough to effectively blind me. It might matter that I was using my dynamo light, which is not nearly as bright as a lot of small battery lights.
It was very much like having a car's high beams shining into your eyes.

I recently bought a modest light from Light and Motion. Nice light, well made, but the beam appears to be designed for mountain biking.
When I've designed my own LED bike lights, I pick out optics to produce a beam that is around 7 degrees. This puts enough light far out in front of me without putting too much near me, which impacts my night vision.

This L&M light looks like it has a beam closer to 30 or 40 degrees. There's no reasonable way to aim it low enough to not put the main beam of the light into the eyes of someone coming towards you. I bought it on sale and out of curiosity. I really haven't used it more than a time or two. It makes a good back-up light, or a light for really deserted roads where no one else is around... or as a daytime "be seen" light. At night, with oncoming traffic, it would be so blinding to oncoming traffic that it would be a risk to me.

Unfortunately... I think a lot of folks buy these lights without any idea about what beam pattern is suitable, and only think that brighter is always better.

Steve in Peoria

both my wired tail lights on my trek e-bike and one I added to the tandem they are always on with a bring flash every several seconds. so best of both worlds. but this would eat up batteries pretty fast. I use them and turn the flash off my Garmin radar.

Steve, you're really cool in the way you bring so much expertise and balance to these discussions. But picture Joe Average upon hearing the term "beam pattern." What the heck is beam pattern? Yup, I see badly aimed lights all the time.