gcbryan
Flashlight Enthusiast
RA, if you are still around ... I'm going to switch gears just a bit and ask about the practicality of throw.
I think we would all agree now that throw is a measurement of max intensity of the most collimated portion of the hotspot.
In practical terms max throw is used in a limiting way rather than as an exact distance since weather, eyesight, the target's reflectivity all play a role in whether we can actually see that beam at the max calculated distance. One could determine whether you need a minimum of 1 lux on target or 2 lux or whatever. That's not the issue here.
It's the practical side I'd like your viewpoint on.
We would all also agree that in designing a practical flashlight focal length is important since lumens off center from the Z axis plays a large role in the practicality of that flashlight.
So, I'm not asking about those areas in which everyone is probably already in agreement.
My question (practically speaking) is max throw as has been defined actually what contributes to throw as we visually experience it? I'm really asking I guess how large is that Z axis beam that you are measuring with a pinhole in your lux meter by the time it only produces 1 lux at it's maximum throw?
Is this something that our eye can actually distinguish? If so then max throw is a useful thing. If not then shouldn't we use some form of average throw (meaning average lux in the hotspot)?
I'm trying to figure out if practically speaking we need to consider the throw that comes from the sidespill (your term) if at a certain distance sidespill is the only reason we can see the hotspot? Part of what I'm asking it how intense is the beam just to the side of the Z-axis (one beam over so to speak)? If it's almost as bright then that would be affected by focal length and it may be the only reason we can see the subject at a certain distance.
Again, when I look at the hotspot on the wall in front of me using an aspheric I see the image of the emitter. I'm not aware that it's brighter in the very center.
When I shine that light outside and try to find maximum throw the spot I see (that illuminates the subject) is also of the entire emitter shape.
Focal length would change how much lumens were in this area correct? If so, in a practical sense, isn't the focal length effecting throw?
I'm not disputing the point you've been making. I'm just coming up with the term "practical throw" or "average throw" to try to describe how flashlights are actually used.
I'm not suggesting that term be considered however if you can tell me that max throw (as we've been talking about it) is enough for the human eye to make use of it at some "max" distance.
In other words, we all already know that more lumens in the beam of a flashlight is more practical but that's not what I'm getting at. I just want to know if max throw actually works with our perceptions outside of theory.
I'm asking because I don't know how large the max intensity spot is at max distance. If it's usable then that's the answer and everything else is just lumens for a bigger spot.
If it's not large enough to be usable then those lumens are necessary in a practical sense for throw. Which is it?
Thanks.
I think we would all agree now that throw is a measurement of max intensity of the most collimated portion of the hotspot.
In practical terms max throw is used in a limiting way rather than as an exact distance since weather, eyesight, the target's reflectivity all play a role in whether we can actually see that beam at the max calculated distance. One could determine whether you need a minimum of 1 lux on target or 2 lux or whatever. That's not the issue here.
It's the practical side I'd like your viewpoint on.
We would all also agree that in designing a practical flashlight focal length is important since lumens off center from the Z axis plays a large role in the practicality of that flashlight.
So, I'm not asking about those areas in which everyone is probably already in agreement.
My question (practically speaking) is max throw as has been defined actually what contributes to throw as we visually experience it? I'm really asking I guess how large is that Z axis beam that you are measuring with a pinhole in your lux meter by the time it only produces 1 lux at it's maximum throw?
Is this something that our eye can actually distinguish? If so then max throw is a useful thing. If not then shouldn't we use some form of average throw (meaning average lux in the hotspot)?
I'm trying to figure out if practically speaking we need to consider the throw that comes from the sidespill (your term) if at a certain distance sidespill is the only reason we can see the hotspot? Part of what I'm asking it how intense is the beam just to the side of the Z-axis (one beam over so to speak)? If it's almost as bright then that would be affected by focal length and it may be the only reason we can see the subject at a certain distance.
Again, when I look at the hotspot on the wall in front of me using an aspheric I see the image of the emitter. I'm not aware that it's brighter in the very center.
When I shine that light outside and try to find maximum throw the spot I see (that illuminates the subject) is also of the entire emitter shape.
Focal length would change how much lumens were in this area correct? If so, in a practical sense, isn't the focal length effecting throw?
I'm not disputing the point you've been making. I'm just coming up with the term "practical throw" or "average throw" to try to describe how flashlights are actually used.
I'm not suggesting that term be considered however if you can tell me that max throw (as we've been talking about it) is enough for the human eye to make use of it at some "max" distance.
In other words, we all already know that more lumens in the beam of a flashlight is more practical but that's not what I'm getting at. I just want to know if max throw actually works with our perceptions outside of theory.
I'm asking because I don't know how large the max intensity spot is at max distance. If it's usable then that's the answer and everything else is just lumens for a bigger spot.
If it's not large enough to be usable then those lumens are necessary in a practical sense for throw. Which is it?
Thanks.
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, though the most important things are already said (praise RA 
