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Blinking Lights During the Day on Roads and Streets

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Blinking Lights During the Day on Roads and Streets

Old 07-29-20, 09:03 AM
  #101  
livedarklions
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Originally Posted by Phoenix800 View Post
Consider:

It’s been two and a half years since the driver of a car coming from the opposite direction turned left into you as you were riding through an intersection.

You have $400K in medical bills, you missed a year of work, you have $35K in other expenses, and you live in constant pain from two fused vertebrae in your neck. You will never ride a bicycle again.

At the trial, the driver’s attorney is trying to convince the jury that the driver is not at fault because she didn’t see you. “It’s hard to see a bicycle,” he argues. Two members of the jury despise bicyclists.

Scenario 1:

Your attorney argues that you had the right of way and that the driver had the legal duty to yield to you on your bicycle.

Scenario 2:

Your attorney argues that you had the right of way and that the driver had the legal duty to yield to you on your bicycle.

Your attorney turns on your 650 lumen flashing headlight, slowly pans it across the jury, points it at the defendant and asks, “You didn’t see this?”

Uhh, no, the defense then points out that you just demonstrated to the jury how bad it is to have a light like that shined into your eyes and says you blinded and disoriented the driver. The defense is going to be aware of the light as a piece of evidence as it would have had to have been disclosed in pre-trial discovery, so that's going to be their version of the story. It might actually have the virtue of being true.

Also, the judge might not allow the whole thing because the demonstration is so clearly flawed as the ability to see a flashing light in a courtroom bears absolutely no relationship to how that light would be perceived on the street. The demonstration then is unduly prejudicial.

Also, keep in mind, most U.S. states are contributory negligence states where the award is based on a proportion of the blame. All you might be accomplishing is that while the driver will be found liable for negligently failing to yield (probably a no-brainer even without a light in daylight), your award may be reduced by some amount if the jury finds that your unreasonably bright flashing light was one of the causes of the crash.

Stupid argument--hypothetical trial tactics based on a hypothetical situation. And trust me,even if the judge allows it, the jury isn't going to appreciate having the plaintiff's attorney shining a flashing light in their eyes. Think they were ill-disposed to bicyclists when they entered that courtroom? You just made that 100 times worse.

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Old 07-29-20, 12:53 PM
  #102  
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He said this and someone else says that. And we still have people talking about flashing lights at night as if that is what this topic is about. But it's not. Read the OP's title:
Blinking Lights During the Day on Roads and Streets
Too much confusion and elevated hormones.
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Old 07-30-20, 04:27 PM
  #103  
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Originally Posted by livedarklions View Post
I don't do it but I think it's possible that you might get some benefit if you're riding in the shade and maybe some stuff I haven't thought of. The main thing, though, is it doesn't really have a downside risk like the flashers you and I were talking about do and they're not an optical assault on other people. If something on a person's bike does no harm and makes the rider feel safer, it's officially none of my business to argue it with them.
I guess there could be a slight chance but still I will always support and advocate solid lights at the front.
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Old 07-30-20, 04:29 PM
  #104  
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Originally Posted by njkayaker View Post
This isnít correct.

Lights, in general, are rarely needed during the day (what the OP was talking about).

A flashing front light is useful in intersections. Cars see you sooner and are less likely to turn in front of you.
They see you sooner with a light that isn't always on? That doesn't sound at all correct. I can see saying that with a bright front light that is solid coming towards them.
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Old 07-30-20, 05:05 PM
  #105  
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Originally Posted by veganbikes View Post
They see you sooner with a light that isn't always on? That doesn't sound at all correct. I can see saying that with a bright front light that is solid coming towards them.
Yes, flashing lights (of the same size/power) are more noticeable from farther away.

Keep in mind that it's not just "seeing". It's making things distinct from other things that are being seen that are competing for attention.

Why do airplanes, towers, and emergency vehicles use flashing lights? It's not to be less noticeable.

Things that are moving/changing get registered more quickly by human visual perception.

Keep in mind that the lights used on bicycles are small.

Originally Posted by veganbikes View Post
I guess there could be a slight chance but still I will always support and advocate solid lights at the front.
Contrary to how human perception works.

Anyway, why just the front light?

===================

Keep in mind that, at night, a flashing front makes it harder for you to see the road and is especially distracting to oncoming traffic.

This thread is talking about daytime. In daytime, you don't need the front light to see and the high level of ambient light makes it less distracting to other drivers.

From far enough away, a static front light might look like a solar reflection off a car windshield. It's much more clear that it's something else if it is flashing.

Last edited by njkayaker; 07-31-20 at 04:25 AM.
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Old 07-30-20, 06:56 PM
  #106  
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Originally Posted by veganbikes View Post
I guess there could be a slight chance but still I will always support and advocate solid lights at the front.

There's one big difference between you and me. In your case, what other people buy literally is your business. Me, not so much.
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Old 07-31-20, 09:16 PM
  #107  
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Originally Posted by livedarklions View Post
There's one big difference between you and me. In your case, what other people buy literally is your business. Me, not so much.
True though I don't actually own the business. But even if I somehow lost my head and left the industry to sit at a desk and file TPS reports all day I would say the same things unless I really went off the super deep end.
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Old 08-01-20, 06:01 AM
  #108  
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Originally Posted by 63rickert View Post
I do not have photosensitive epilepsy. I do get splitting headaches from your strobe lights. If I fail to drop dead directly in front of you do I have any grounds for complaint?

This has been discussed with my neurologist. She tells me I am near the bottom of the spectrum and no one would ever diagnose me with epilepsy or treat me for epilepsy. But I am on the spectrum. She also tells me that strobing bike lights come up in her clinical practice every day. No deaths reported yet so bikeforums does not care.

The whole idea of a flashing light is to attract attention. It does attract attention. That is simply s physiological response and you canít turn it off. It is not possible to disregard that flashing light. If it is a blinking light at reasonable power and not aimed directly in my eyes I do not care. High powered lights, strobing lights, strange patterned lights are all major distractions. They make it less possible for me to see what is going on up the road. Some part of my attention is forcibly taken by that strobe light and makes it less possible to ride safely. Now try it with three riders ahead, or six riders ahead, all with patterned and powerful lights. Or try to ride when the rider ahead has six flashing lights all on one bike. Maybe you can manage that, I canít.

I will never again be able to participate in a group ride. No chance. Popular nearby cycling routes are all dicey, fewer and fewer safe places to ride. Ride at night? Forget it, canít do that any more. You have taken all that away from me.

Flashing lights make us all less safe. The sort of ego that transforms these bludgeon lighting devices into ďsafetyĒ is incomprehensible.
cool story bro
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Old 08-02-20, 12:18 PM
  #109  
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I use a Niterider on flash mode during the daytime. I have it angled straight outward, and I tip it down after I see an approaching car until it passes me. A powerful flash allows vehicles to immediately acknowledge my presence on the road.
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Old 08-02-20, 01:54 PM
  #110  
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It's worth noting that flashing aviation lights do not improve visual detection until the intensity is close to the visual threshold (very dim). Otherwise, the steady light is superior for "being seen". Steady lights are also superior for closing rate detection.

So a better idea would be a steady bright headlight to maximize our visibility - two or more if we want to aid drivers' judgement of closing rate - and a blinking light only additionally if we're worried about being noticed from a greater distance, at the edge of visible detection.

"Aviation aviation signal lighting: impact of lighting characteristics visibility" - John D Bullough
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Old 08-02-20, 04:15 PM
  #111  
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Originally Posted by wphamilton View Post
It's worth noting that flashing aviation lights do not improve visual detection until the intensity is close to the visual threshold (very dim). Otherwise, the steady light is superior for "being seen". Steady lights are also superior for closing rate detection.

So a better idea would be a steady bright headlight to maximize our visibility - two or more if we want to aid drivers' judgement of closing rate - and a blinking light only additionally if we're worried about being noticed from a greater distance, at the edge of visible detection.

"Aviation aviation signal lighting: impact of lighting characteristics visibility" - John D Bullough
What that article is says more complicated than you are saying. Lights during the day (what the OP was talking about) tend to have a high background luminance. Flashing might work better there. The issues with headlights and rear lights aren't going to be the same. The issues between nighttime and daytime (what the OP was talking about) aren't going to be the same. The flashing red lights also serve to identify the object as a cyclist than a small steady red light does. A flashing headlight does the same thing.

Subjective brightness of a short flash can be higher (briefly) than for a longer flash because the visual system lags in processing time relative to the flash duration [38]. Rinalducci and Higgins [39] conclude that increasing the duration of the flash for signal lights longer than 0.2 s will not appreciably improve its conspicuity.
This is implying flashing lights increase conspicuity.

When flashing lights are employed (e.g., to increase conspicuity), sources with rapid onset times provide modest reaction time benefits.
This is implying flashing lights increase conspicuity.

A number of studies have suggested that flashing lights increase the conspicuity of a signal relative to a steady-burning signal light, but flashing lights, by virtue of their reduced total light energy, can have disadvantages relative to steady-burning signals as well.
This is implying flashing lights increase conspicuity but that there might be issues with flashing over steady lights.

And the article appears to be talking about runway lights (not much light bicycle lights).

Well above visual threshold, the detection of a signal light that is steady burning is improved over a flashing signal light (with a maximum intensity equal to that of the steady-burning signal), in a manner consistent with effective intensity [27].
It's "well above" visual threshold that steady works better.

The "closing rate detection" isn't an issue. The idea is to be conspicuous from a long way away. Long before "closing" becomes a concern.

Why do they use strobes in rescue situations? Why do they use strobes on airplanes?

Last edited by njkayaker; 08-02-20 at 04:30 PM.
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Old 08-02-20, 04:37 PM
  #112  
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https://www.bellinghamherald.com/news/traffic/rules-of-the-road/article178572796.html#:~:text=A%20Dutch%20study%20reviewed%20various,light%20than%20a%20continuous%2 0light.&text=They're%20probably%20right%3B%20a,crashes%20by%20over%2030%20percent.


From a safety perspective, a couple of studies have looked into the effectiveness of blinking lights compared to continuous lights

A
Dutch study reviewed various types of bike lights and found that drivers notice blinking lights sooner, but have a harder time judging the speed and distance of a blinking light than a continuous light.
https://bicycles.stackexchange.com/q...-a-steady-beam


Wood et al. (2009): Drivers’ and cyclists’ experiences of sharing the road: incidents, attitudes and perceptions of visibility. Accident Analysis and Prevention, 41 (4), pp. 772-776

About differences in the visibility as perceived by bikers and drivers:
The largest difference relates to the visibility of cyclists using lights on their bicycles, where cyclists rate themselves as significantly more visible when using bicycle lights than did the drivers. This difference, in turn, is much greater at night than during the day.
Code:
                                      Drivers       Cyclists
Flashing lights on wrists/ankles   4.03 (0.96)    4.23 (0.84)
Bicycle lights                     3.3  (1.15)    4.5  (0.67)
Visibilty on scale 1 to 5; parentheses: standard deviation.

So cyclists think they are both equivalent, with a possible small advantage for the steady light, while drivers thought the flashing lights to be more visible (but remember differences between detection and recognition, see below) to be better, but still less visible than the bikers thought the flashing light.

With regard to the distance:
An analysis was also performed with regard to the average distance at which drivers and cyclists believed that a cyclist would be visible to a driver using low-beam headlamps at night. On average, cyclists believed themselves to be visible from 110.3 metres (sd = 157.662), while drivers believed a cyclist would only be visible at 48.3 metres (sd = 58.69) on average (that is, at less than half the distance estimated by the cyclists), t (1424) = - 9.247, p < .001.
Probably even more important than deciding whether flash or steady light is better, is actually using the light:
While the use of visibility aids was advocated by cyclists, this was not reflected in self-reported wearing patterns
*(emphases mine)s
Maybe this Cochrane review: Interventions for increasing pedestrian and cyclist visibility for the prevention of death and injuries is useful for background info, and they have a few comparisons of steady light vs. reflector and blinking light vs. reflector:
Blomberg 1986: A flashing light held by a pedestrian yielded a greater detecti on and recognition distance when compared with reflectorised accessories (420m versus 207m and 96m versus 92m respectively).
Watts 1984b: A rear bicycle lamp yielded a greater detection distance when compared with reflectors (306m versus 184m).
Watts 1984c: A flashing beacon on a bicycle yielded a greater detection but not recognition distance when compared with reflectors (588m versus 444m and 59m versus 71m respectively)

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Old 08-02-20, 04:49 PM
  #113  
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This is about bicycle lights (not airports).

https://cyclingtips.com/2017/02/see-...unning-lights/

Steady daytime running lights, similar to what are used on motor vehicles, may not be enough to make road cyclists any more visible than if they went without. Remember that that selective attention phenomenon conditions drivers to look for other four-wheeled motor vehicles, so the odds are already stacked against us. Motorcyclists have used daytime running lights for years, for example, and that user group is all too familiar with how steady DRLs offer only modest protection against the driver that “just didn’t see you.”

Motorcyclists have since moved more toward flashing front and rear DRLs, and cyclists have followed suit.

“Brightness at the source does not necessarily mean bright where it is intended to be seen from; lumens are not everything,” said Applegate. “The lensing, flash pattern, and range of the light are equally important. When designing effective daytime running lights, you need an interruptive flash pattern that draws the attention of drivers. You want not just to be visible, but to be recognized. There is a difference.”
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Old 08-04-20, 09:18 AM
  #114  
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Originally Posted by njkayaker View Post
Well above visual threshold, the detection of a signal light that is steady burning is improved over a flashing signal light (with a maximum intensity equal to that of the steady-burning signal), in a manner consistent with effective intensity [27].
It's "well above" visual threshold that steady works better.

Reading that more closely, that is not at all the implication. It's talking about "effective intensity" which is simply the average intensity during the on-off cycle, and stating that the improvement of the steady light is related to the effective intensity.

Don't cherry pick. They state unambiguously that flashing lights are more visible only close to the visual threshold (when you can barely see the steady light)


The "closing rate detection" isn't an issue. The idea is to be conspicuous from a long way away. Long before "closing" becomes a concern.
It is for me. I don't care at all whether a driver can see me from 2 minutes away. I want him to see me during the time when he's approaching me and is judging how to interact. I'd rather he have more information about how quickly he's approaching than be confused about it.

Why do they use strobes in rescue situations? Why do they use strobes on airplanes?
Strobes convey information.
Airplane position lights are not strobed.
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Old 08-04-20, 10:09 AM
  #115  
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Originally Posted by wphamilton View Post
Reading that more closely, that is not at all the implication. It's talking about "effective intensity" which is simply the average intensity during the on-off cycle, and stating that the improvement of the steady light is related to the effective intensity.
Read it more closely. The effect you are repeating occurs "Well above visual threshold".

And I show it repeated multiple times.


Originally Posted by wphamilton View Post
Don't cherry pick
That's what you did!

I also showed sources that talk about bicycle lights (not airports).

Originally Posted by wphamilton View Post
It is for me. I don't care at all whether a driver can see me from 2 minutes away.
Sure you do!

You want drivers to have as long as possible to be able to be aware of you (and have some idea what you are) for as long as possible. It makes the window larger (hopefully) than the distraction window or gives more time for your presence to reach their consciousness. This is the point of the flashing light (not the other thing).

Originally Posted by wphamilton View Post
I want him to see me during the time when he's approaching me and is judging how to interact. I'd rather he have more information about how quickly he's approaching than be confused about it.
Keep in mind that the OP was talking about lights during daytime (why do people keep forgetting that?).

If the driver is that close, they aren't (shouldn't be) looking at your rear light.

In practice, "how to interact" doesn't seem to be an issue at all.

You have to register as something that might need to interact with before they can judge how to interact.

That registration appears to be the real problem, with bicyclists and motorcyclists. There appears to be a perceptual blindness that keeps these things from registering with drivers.

If the bicyclist/motorcyclist registers, drivers don't appear to have issues interacting OR they can't see the rear light anyway.

Last edited by njkayaker; 08-04-20 at 10:52 AM.
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Old 08-04-20, 01:57 PM
  #116  
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Originally Posted by 63rickert View Post
I do not have photosensitive epilepsy. I do get splitting headaches from your strobe lights. If I fail to drop dead directly in front of you do I have any grounds for complaint?

This has been discussed with my neurologist. She tells me I am near the bottom of the spectrum and no one would ever diagnose me with epilepsy or treat me for epilepsy. But I am on the spectrum. She also tells me that strobing bike lights come up in her clinical practice every day. No deaths reported yet so bikeforums does not care.

The whole idea of a flashing light is to attract attention. It does attract attention. That is simply s physiological response and you canít turn it off. It is not possible to disregard that flashing light. If it is a blinking light at reasonable power and not aimed directly in my eyes I do not care. High powered lights, strobing lights, strange patterned lights are all major distractions. They make it less possible for me to see what is going on up the road. Some part of my attention is forcibly taken by that strobe light and makes it less possible to ride safely. Now try it with three riders ahead, or six riders ahead, all with patterned and powerful lights. Or try to ride when the rider ahead has six flashing lights all on one bike. Maybe you can manage that, I canít.

I will never again be able to participate in a group ride. No chance. Popular nearby cycling routes are all dicey, fewer and fewer safe places to ride. Ride at night? Forget it, canít do that any more. You have taken all that away from me.

Flashing lights make us all less safe. The sort of ego that transforms these bludgeon lighting devices into ďsafetyĒ is incomprehensible.
I can't agree with your last paragraph for a second. Tve use of flashing lights doesn't indicate an unskilled cyclist--it is merely an acknowledgement that one shares the road with subhuman unskilled and inattentive drivers. I take my chances by using a steady headlight and 2 blinkers. I consider polite lighting a luxury to indulge if American drivers are ever human again.
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Old 08-07-20, 03:47 PM
  #117  
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Originally Posted by CycleNutz View Post
I use a Niterider on flash mode during the daytime. I have it angled straight outward, and I tip it down after I see an approaching car until it passes me. A powerful flash allows vehicles to immediately acknowledge my presence on the road.
I, too, use a headlight on "flasher" mode during the daytime.

In my own experience seeing other approaching cyclists, whether walking, riding or driving in a car (often on two-lane roads [one lane each direction], often on four-lane roads), I tend to notice flashing-headlight cyclists far sooner. There's something about the different lighting that sets it apart from the other visual mess around the light. Plenty of other non-moving bright spots, out there, on typical roadways around where I live. And a steady-state bright spot just gets lost in the mess, all too often.

A flasher, though, is different, and stands out more clearly in such clutter. I also tend to experience far fewer close-brushes with passing vehicles that have approached from the rear, when I'm doing daytime flashers. Whatever else can be said about a steady-state light. Anecdotal, sure, but there's generally a noticeable difference when I'm out there riding, when I've got flashers going versus not.

Am building up a bike now, and it'll have a steady headlight and a second, flashing headlight ... along with a couple of taillights (a steady and a flasher). Hard to know for certain what a given driver, the next one coming along, is going to see most readily. But I find in the daytime it's the flashers that grab my attention soonest.

JMOE
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Old 08-08-20, 01:37 PM
  #118  
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Originally Posted by njkayaker View Post
Read it more closely. The effect you are repeating occurs "Well above visual threshold".


It says that at well above visual threshold, *how much* a steady light is better than flashing is directly related to the relative intensity. It does *not* say that flashing lights are more visible only at "well above visual threshold". It does say elsewhere that steady lights are more visible at close to visual threshold. Not only cherry-picking, but you misinterpret your cherry-picked line.


You want drivers to have as long as possible to be able to be aware of you (and have some idea what you are) for as long as possible. It makes the window larger (hopefully) than the distraction window or gives more time for your presence to reach their consciousness. This is the point of the flashing light (not the other thing).
It is the point, but not a well thought out one. In fact it is almost irrelevant for drives to be aware of you "for as long as possible" before reaching you. If they can see me at, say, 1000 feet, they absolutely have plenty of time to plan how to interact. And yes, the interaction (which means passing safely or running over you for instance) is the only thing we need to be concerned about.

I don't care if they notice me from half a mile away, a minute or two before getting close. Most drivers don't pay any attention to anything going on at that distance anyway.
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Old 08-08-20, 03:26 PM
  #119  
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Originally Posted by wphamilton View Post
It says that at well above visual threshold, *how much* a steady light is better than flashing is directly related to the relative intensity.
No, you are still reading it wrong. It's "well above" that it's "improved" over flashing (below this level it's not better than flashing).
And you are ignoring the other quotes. And it's about airports (not cyclists). And airports use flashing lights for many things.

Originally Posted by wphamilton View Post
It is the point, but not a well thought out one. In fact it is almost irrelevant for drives to be aware of you "for as long as possible" before reaching you. If they can see me at, say, 1000 feet, they absolutely have plenty of time to plan how to interact.
It's not how long they see you. It's how long they have to be able to see you. And it's not just seeing anyway. It's seeing and recognizing that it's a cyclist (or something they have to deal with) If they can recognize you from farther away, it should reduce the likelihood that they will do something else like look at their phone.

Originally Posted by wphamilton View Post
And yes, the interaction (which means passing safely or running over you for instance) is the only thing we need to be concerned about.
No. They have to register your existence before interacting with you. If they register your existence and fail to interact with you safely, it's not a problem with the light.

You want them to recognize you before they have to interact with you anyway (it's surprising you don't know that).

The other thing that you and other keep missing is that people are trained to understand that flashing lights indicate a warning. Steady lights don't convey that meaning nearly as much (if at all).

Last edited by njkayaker; 08-08-20 at 04:16 PM.
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Old 08-08-20, 05:15 PM
  #120  
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Originally Posted by njkayaker View Post
No, you are still reading it wrong. It's "well above" that it's "improved" over flashing (below this level it's not better than flashing).
"in a manner consistent with effective intensity. " Below that, also improved but not in a manner consistent with effective intensity. What's so hard about that?
And you are ignoring the other quotes.
You're welcome - I was being charitable by ignoring them.

Airports do use flashing lights for many things - and for many reasons, which are not the one reason that you claim they're for. That's one reason why your airport analogy is so silly.
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Old 08-08-20, 06:35 PM
  #121  
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Originally Posted by wphamilton View Post
"in a manner consistent with effective intensity. " Below that, also improved but not in a manner consistent with effective intensity. What's so hard about that?
Your reading is still wrong. The improvement (above the threshold) is consistent (related to) with effective intensity.

Well above visual threshold, the detection of a signal light that is steady burning is improved over a flashing signal light (with a maximum intensity equal to that of the steady-burning signal), in a manner consistent with effective intensity [27]. When the intensity of a signal light is reduced such that it approaches the visual threshold, the relationship between steady-burning and flashing signals is reversed in opposition to effective intensity [27].
The part you ignored. So, below visual threshold, flashing is better detected. "Well above", steady is better detected. Presumably, in between, it's about the same.

Below "well above", the relationship is reversed.

That is, what was an "improved" relationship "well above" is a relationship reversed from "improved" below that.

Originally Posted by wphamilton View Post
I was being charitable by ignoring them.
No, you were cherry picking.

Originally Posted by wphamilton View Post
Airports do use flashing lights for many things - and for many reasons, which are not the one reason that you claim they're for. That's one reason why your airport analogy is so silly.
The one article you linked to was talking about airports. It's your "airport analogy"!

Last edited by njkayaker; 08-11-20 at 12:19 PM.
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Old 08-08-20, 07:02 PM
  #122  
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https://ntrs.nasa.gov/citations/19750023659

Conspicuity of target lights: The influence of flash rate and brightnessThe stimulus characteristics of lights that might aid a pilot to see and avoid, by alerting him to a potential threat were studied. The relative conspicuity of foveally equated, point-source, steady and flashing lights of several brightnesses, seen against a star background was examined. From the subject's viewpoint, these target lights could appear anywhere within a large (40 deg horizontal by 35 deg vertical) field of view. The lights appeared at random time intervals while the subject was periodically distracted by a simulated cockpit task. The results indicate that correct target detection increases and reaction time decreases with increased target intensity. Steady lights are missed more frequently and acquired more slowly than flashing lights, but no significant differences are found among the wide range of flash rates employed. The intensity of the light has a greater effect on both detection and reaction time to steady lights than to flashing lights. These results are compared with results of other researchers who used targets which appeared at fixed locations. The longest reaction times were recorded to lights which appeared either at the extremes or at the very center of the visual field.
https://journals.sagepub.com/doi/abs...93129503902105

Mariners frequently have trouble distinguishing lighted aids to navigation in areas with a high density of background lights. The Coast Guard is seeking ways to enhance the conspicuity, or likelihood of being noticed, of these aids. Literature has shown that a flashing light is more conspicuous than one that is steady. To improve conspicuity by determining optimal flash characteristics, we had 20 observers search for a flashing point of light among backgrounds of steady lights on a CRT screen. In single 360-trial sessions, observers indicated which of five screen sectors contained the flashing target, and accuracy and response time were recorded. Targets were flashed at 1, 2, and 3.85 Hz, each at duty cycles of .3, .5, and .8. An ANOVA showed significant effects of frequency, duty cycle, and background light density. Search time increased with number of background lights. Conspicuity improved as frequency increased and as duty cycle decreased.
https://tigerprints.clemson.edu/cgi/...ext=all_theses

The findings indicate that there are conspicuity advantages of using lights with dynamic qualities (e.g., flashing or moving spatially), as opposed to static qualities when cycling at night.
https://www.roadbikerider.com/incisive-new-studies-on-cyclist-visibility-d3/ (referencing the Clemson study)

This time, the researchers found, during the day, “that from a distance of 200 meters…a flashing tail light is significantly more conspicuous than an always-on tail light, which in turn is significantly more conspicuous than” no tail light at all.
https://vtechworks.lib.vt.edu/handle/10919/99387

The results indicate that active visibility treatments, such as bicycle-mounted lights, make cyclists more conspicuous than passive systems like retroreflective vests and biomotion bands. Flashing headlamps and tail lamps were the most conspicuous treatments during both the day and at night; fast flashing headlamps (6.7 Hz) had higher detection distances and rates during the day, and moderately fast flashing headlamps (3.4 Hz) had higher detection distances and rates at night. Spoke lights and flashing tail lamps, along with retroreflective vests, also aided cyclist visibility during the day and at night, especially for vehicles approaching intersecting cyclists.
https://www.osapublishing.org/josa/a...=josa-43-7-567

The present study compares steady and flashing light signals with respect to conspicuity, defined as the speed of response to a signal above threshold. For large signal contrasts the conspicuity of steady and flashing signals is approximately equal. For small contrasts the conspicuity of flashing signals is considerably greater. These results suggest that flashing rather than steady signals be used for warning purposes.

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Old 08-08-20, 10:22 PM
  #123  
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My forward white and rearward red blinking lights are for four wheelers to see me. Period.
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Old 08-09-20, 03:17 AM
  #124  
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If it's heavily overcast then I can see where a flashing (NOT strobing) light can be useful; if your bike and clothing are dark colours and you are riding in deep shade. In bright daylight? Not so much unless you have a really powerful light. My experience is that on a sunny day I see the bicyclist long before I notice their flashing front light.

I've also noticed that often a flashing rear red light on a bicycle ahead of me looks like a flashing red car taillight - in other words it's lost in all the other car taillights especially at intersections.

Cheers
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Old 08-10-20, 02:20 PM
  #125  
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Originally Posted by Miele Man View Post
If it's heavily overcast then I can see where a flashing (NOT strobing) light can be useful; if your bike and clothing are dark colours and you are riding in deep shade. In bright daylight? Not so much unless you have a really powerful light. My experience is that on a sunny day I see the bicyclist long before I notice their flashing front light.
No one is saying that lights are always better (nothing will be!) but you aren't saying they are worse.

Even in bright daylight, I can see the flashing lights from much farther away.

Originally Posted by Miele Man View Post
I've also noticed that often a flashing rear red light on a bicycle ahead of me looks like a flashing red car taillight
That could be an advantage.

Originally Posted by Miele Man View Post
- in other words it's lost in all the other car taillights especially at intersections.
If it's "lost", the cyclist without the light is likely going to be "lost" too.

No one is claiming that lights always work. Nothing you said is any indication that cyclist are worse off having them.

Last edited by njkayaker; 08-10-20 at 02:26 PM.
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