ronniepudding
Enlightened
I'm trying to help my brother choose a new headlamp, and I've narrowed it down to the Zebralight H502. However there are several emitter choices, and I'm trying to explain them. Have I done a good job of explaining this in an unbiased way? I'd also be curious to hear if I've gotten anything wrong in the description that follows. [Note that I am not recommending the cool white tint to him because I'm not personally fond of them in headlamps -- no offense to those that like CW. But other than that, I'm not trying to sway him in favor of any particular option.]
There are a couple of choices to be made. I think the main choice is whether to forgo output and get better color rendering (high Color Rendering Index, or "CRI") and/or a warmer tint, -- or on the other hand get max brightness and accept a more washed-out light quality.
Zebralight has a number of choices for which emitter you want in their headlamps. I would go with one of the following (in order of brightness):
1) Cree XM-L2 neutral white tint (CCT 4,400K); CRI = 75 (out of 100), max lumens = 260
2) Rebel High CRI daylight tint (CCT 5,000K); CRI = 85, max lumens = 170 (will be bluer than XM-L2, but with better color reproduction)
3) Rebel High CRI neutral white tint (CCT 4,000K); CRI = 85, max lumens = 142 (will be yellower than both 1 & 2, more like an incandescent bulb... again with better color reproduction than the XM-L2)
A bit more explanation on tint... the CCT # (correlated color temperature) describes the relative warmth or coolness of the light produced by the emitter. A higher number will be cooler (or bluer), and a lower number will be warmer (or yellower, more like an incandescent bulb). All this is somewhat subjective, since the critical factor is the eye of the beholder so to speak, -- and different people perceive colors differently. In any case, 5,000K is approximately "soft daylight", and so that's sort of a good reference point.
In general, the quality of color produced by an LED can be described by a combination of CCT and CRI. Warmer temperature (lower CCT), and better color rendering (higher CRI), will both negatively impact output/brightness, as measured in lumens. Thus choice #3 would be considered by many to be the "best" quality tint, but outputs fewer lumens than the other choices. Choice #1 is brightest on max, but will appear more washed-out and flat looking than the other choices.
In the end, any of these lights will be 10 times better than the old Tikka we're replacing on all counts, so don't get too hung up on this. Also, consider that while the difference between 260 and 142 lumens will be noticeable, the difference between 170 and 142 will be hard to discern (i.e., it's not a linear scale).
The decision really comes down to how you intend to use the light:
A) The high (260 lm) output on the XM-L2 is going to be useful in a pinch when walking over rough or unfamiliar terrain... you can set the light on max and see into the distance much better than with the Rebel lights. The battery won't last long at max output though, and as discussed, you're better off using a dedicated, more throwy flashlight for this purpose if you intend to hike at night. But in an emergency, it might be nice to have that ability, if only for a short time.
B) The 142-170 lm output on the Rebel lights is no slouch compared to what you're used to, but it's not going to be as good as the XM-L for lighting power. What it will do is make the colors "pop" in objects close by. A couple of other factors in favor of the Rebel is that it's inherently less floody than an XM-L2, so it will marginally project forward a bit better. Also, while the XM-L2 is more efficient on high output modes, the Rebel is actually more efficient (preserving battery reserves) when used on medium and low modes. Typically when camping in the dark (or working on a car), you'll use the high mode pretty infrequently, if at all, and medium will handle most needs.
So how did I do? Anything I should correct? Any other factors or additional criteria that you'd use when choosing between these LEDs? What would be your choice? (I'd go with #3, but I think that's because it's an excuse to also carry a thrower while camping
There are a couple of choices to be made. I think the main choice is whether to forgo output and get better color rendering (high Color Rendering Index, or "CRI") and/or a warmer tint, -- or on the other hand get max brightness and accept a more washed-out light quality.
Zebralight has a number of choices for which emitter you want in their headlamps. I would go with one of the following (in order of brightness):
1) Cree XM-L2 neutral white tint (CCT 4,400K); CRI = 75 (out of 100), max lumens = 260
2) Rebel High CRI daylight tint (CCT 5,000K); CRI = 85, max lumens = 170 (will be bluer than XM-L2, but with better color reproduction)
3) Rebel High CRI neutral white tint (CCT 4,000K); CRI = 85, max lumens = 142 (will be yellower than both 1 & 2, more like an incandescent bulb... again with better color reproduction than the XM-L2)
A bit more explanation on tint... the CCT # (correlated color temperature) describes the relative warmth or coolness of the light produced by the emitter. A higher number will be cooler (or bluer), and a lower number will be warmer (or yellower, more like an incandescent bulb). All this is somewhat subjective, since the critical factor is the eye of the beholder so to speak, -- and different people perceive colors differently. In any case, 5,000K is approximately "soft daylight", and so that's sort of a good reference point.
In general, the quality of color produced by an LED can be described by a combination of CCT and CRI. Warmer temperature (lower CCT), and better color rendering (higher CRI), will both negatively impact output/brightness, as measured in lumens. Thus choice #3 would be considered by many to be the "best" quality tint, but outputs fewer lumens than the other choices. Choice #1 is brightest on max, but will appear more washed-out and flat looking than the other choices.
In the end, any of these lights will be 10 times better than the old Tikka we're replacing on all counts, so don't get too hung up on this. Also, consider that while the difference between 260 and 142 lumens will be noticeable, the difference between 170 and 142 will be hard to discern (i.e., it's not a linear scale).
The decision really comes down to how you intend to use the light:
A) The high (260 lm) output on the XM-L2 is going to be useful in a pinch when walking over rough or unfamiliar terrain... you can set the light on max and see into the distance much better than with the Rebel lights. The battery won't last long at max output though, and as discussed, you're better off using a dedicated, more throwy flashlight for this purpose if you intend to hike at night. But in an emergency, it might be nice to have that ability, if only for a short time.
B) The 142-170 lm output on the Rebel lights is no slouch compared to what you're used to, but it's not going to be as good as the XM-L for lighting power. What it will do is make the colors "pop" in objects close by. A couple of other factors in favor of the Rebel is that it's inherently less floody than an XM-L2, so it will marginally project forward a bit better. Also, while the XM-L2 is more efficient on high output modes, the Rebel is actually more efficient (preserving battery reserves) when used on medium and low modes. Typically when camping in the dark (or working on a car), you'll use the high mode pretty infrequently, if at all, and medium will handle most needs.
So how did I do? Anything I should correct? Any other factors or additional criteria that you'd use when choosing between these LEDs? What would be your choice? (I'd go with #3, but I think that's because it's an excuse to also carry a thrower while camping
