Blinking Lights During the Day on Roads and Streets
#101
Clark W. Griswold
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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.
#102
Clark W. Griswold
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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.
#103
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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.
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.
#104
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#105
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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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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 can’t 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 can’t.
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, can’t 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 “safety” is incomprehensible.
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 can’t 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 can’t.
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, can’t 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 “safety” is incomprehensible.
#107
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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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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
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
#109
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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
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
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.
When flashing lights are employed (e.g., to increase conspicuity), sources with rapid onset times provide modest reaction time benefits.
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.
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].
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.
#110
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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.
https://bicycles.stackexchange.com/q...-a-steady-beam
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.
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.
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.
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)
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)
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)
Last edited by njkayaker; 08-02-20 at 04:41 PM.
#111
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This is about bicycle lights (not airports).
https://cyclingtips.com/2017/02/see-...unning-lights/
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.”
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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#112
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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.
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.
Why do they use strobes in rescue situations? Why do they use strobes on airplanes?
Airplane position lights are not strobed.
#113
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And I show it repeated multiple times.
That's what you did!
I also showed sources that talk about bicycle lights (not airports).
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).
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.
#114
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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 can’t 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 can’t.
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, can’t 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 “safety” is incomprehensible.
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 can’t 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 can’t.
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, can’t 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 “safety” is incomprehensible.
#115
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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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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).
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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And you are ignoring the other quotes. And it's about airports (not cyclists). And airports use flashing lights for many things.
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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And you are ignoring the other quotes.
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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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].
Below "well above", the relationship is reversed.
That is, what was an "improved" relationship "well above" is a relationship reversed from "improved" below that.
No, you were cherry picking.
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.
#120
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https://ntrs.nasa.gov/citations/19750023659
https://journals.sagepub.com/doi/abs...93129503902105
https://tigerprints.clemson.edu/cgi/...ext=all_theses
https://www.roadbikerider.com/incisive-new-studies-on-cyclist-visibility-d3/ (referencing the Clemson study)
https://vtechworks.lib.vt.edu/handle/10919/99387
https://www.osapublishing.org/josa/a...=josa-43-7-567
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.
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.
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.
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.
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.
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.
Last edited by njkayaker; 08-08-20 at 07:25 PM.
#122
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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
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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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.
Even in bright daylight, I can see the flashing lights from much farther away.
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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I'm not bickering with you any longer.
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It was a review (by the way), not a study.
You ignored all the places where the review indicates that flashing lights increase conspicuity.
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].
That is, what was a relationship "improved" "well above" is a relationship reversed from "improved" (degraded) below that.
The improvement above is consistent with the effective intensity.
The degradation (the reverse relationship) below is in opposition to the effective intensity.
https://www.imedpub.com/articles/avi...visibility.pdf
Even a small village is likely to have some lighting that will be maintained on throughout the nighttime period. Since the spatial configuration of such lights would be uncontrolled, the possibility of a chance arrangement similar to the corners of a runway cannot be eliminated. In such a case, both to improve conspicuity of signal lights and to differentiate them from other lights, the use of flashing patterns would appear to be beneficial.
The one article you linked to was talking about airports. It's your "airport analogy"! Why did you reference something "so silly"?
Last edited by njkayaker; 08-11-20 at 12:35 PM.