Im still curious about the moding part of your post. Im still learning the diffrence between lux, cd and lumens. You say that the lux will almost double, can you say that the candela will follow? The difference between candela and lux is that candela is the same at any distance, right?
Is this modifying operation a hard to do with high risks of breaking the light or can anyone, that is abit handy with electonics, do it? Any risks that the light cant handle the extra heat it will produce?
With "effective throw" you mean the ANSI standard?
600m+ sounds awesome. I had a hard time to choose between TM26 and SR95UT, high lumens or a really good throw. With this light, i might get both. :huh:
To add to TheDriver's excellent info:
Think of it this way:
Lumens are what the LED produces, essentially the light that is sent out.
You can't SEE lumens though.
Lux is what you can SEE, its essentially the light that hit a target, and bounced back to your eyes. The higher the lux, the brighter the target appears to be illuminated/the intensity of the illumination.
The lux is the lumens per square meter, with 1 lux = 1 lumen/m2
That intensity drops with distance (The farther away the target, the lower the lux on the target...).
It drops off with distance according to the inverse square law...so, essentially it will be 1/4 as bright at double the distance.
This means that if you know the intensity (lux) at any distance, you can calculate the intensity at other distances.
When they describe the lux at 1 meter, that call it the candela or cd of the light.
They may not MEASURE it at 1 meter though, because throwy lights sometimes have a beam SHAPE that doesn't become representative of its long range abilities until you are 5-50 meters from the light. Essentially, the way a lens focuses the beam, it hasn't yet all come together yet (Collimated, etc..) - so they measure it at the ACTUAL range that its in its final shape/representative intensity, and back-calculate back to a standard 1 meter lux measurement.
That allows direct comparison to other lights also using the same standard 1 meter lux to give the cd of the light.
So if you shined your light at a lux meter from 1 m, you'd get a lower cd than you'd be expecting, etc...you'd need to MEASURE it from further away, then do math)
So, since we can calculate the lux at any given range once we have the cd (Lux at 1 meter), we can then publish a range in meters.
The ANSI standards describe the range of a light in terms of how far it can go before it drops down to 1/4 lux (0.25 lux).
To get that, we simply take the square root of the cd, and multiply it by 2, and that's the METERS at which the intensity will have dropped to 0.25 lux.
If we want the distance to 1 lux, its simply the square root of the cd....and so forth.
To complicate matters, the "ANSI Throw" standard of 0.25 lux is fine for close up vision, but, is not effective for very long ranges.
The reason is that your eyes need to use the sharpest part of your vision to resolve details at long ranges...200-400 meters away for example, objects are proportionally small to you.
This sharp part of you vision is called the fovea, and its about a 2º field of vision. This is why people instinctively squint when trying to resolve things - to reduce their field of view to that fovea.
Unfortunately, this sharp part with great color resolution has about no low light abilities. So, when trying to tell a man carrying wood in his arms from a man carrying firearms 400 meters away, you need to use your fovea, and, at night, that means you need a LOT more light on that guy to tell anything...the 0.25 lux is not going to cut it anymore.
So, when people talk about ANSI Range, they mean to that 0.25 lux. When people talk about EFFECTIVE Range, they typically mean a range that still allows you to actually resolve adequate details...which can vary from person to person, level of night adaptation, etc. Typically, THAT range is somewhere between 1 - 5 lux.
As 1 lux is an easy square root of the cd calculation, and, 1 lux is at least enough light at most distances for SOME people, lux at 1 meter is a common "Effective Range".
In real life YMMV, etc...
Hope that helps to fill in some blanks for you.
