brightnorm
Flashaholic
- Joined
- Oct 13, 2001
- Messages
- 7,160
I could have added this to the "Smallest & brightest SF Turbohead" thread, but I was so surprised and disappointed by my experience that I decided to start a new one.
I just received my KT2 lamp/reflector kit with N2 lamp for my 9P SF. My first impression as I removed it from the box was positive. It had a ruggedly stylish look that was very appealing. It was also more compact than my "classic" 3" Turbohead that I bought for my old 6P years ago: 2.5" diameter and 2.5" length vs 3" and 3" length. It also seemed heavier than the larger and older T-head, but I ignored that in my eagerness to try it.
After I attached it to my 9P and ignited it my heart sank. The beam seemed surprisingly large in diameter and lacking in intensity. I thought that my judgment was perhaps subjective and inaccurate so I got out my 6P with the old 3" turbo and compared the two beams.
The beam from the 6P 3" turbo was about 40-50% smaller than that of the 9P + N2. It was nearly perfectly round with almost no corona so that the light was nearly 95% hotspot. Consequently, it was actually brighter than the larger light even though there was "more" light coming from the 9P. To say that I was disappointed would be an understatement.
Next, I compared them both to my tightly focused US. No contest! Neither Surefire matched the Streamlight, whose beam was only slightly larger than the3" turbo's.
Finally, I put the N2 into the 3" turbohead and attached it to the 9P. Now THERE was a light! The beam was about the same diameter and focus as the US, perhaps a little cleaner with less coronal spread and nearly identically bright.
Now I had a light that was just as bright and penetrating as the US, but much smaller, lighter and easier to carry. Look at the specs:
UltraStinger - L: 11 5/8" Wt: 1lb + 3/10 oz
SF 9P with 3"turbo - L: 8" Wt: 9.5oz
To put it another way, the SF 9P with N2 in that "old, outmoded turbo" provided equivalent performance to the US which is 45% longer and 70% heavier and much more cumbersome to carry. The only negative is the 3" diameter.
It appears that Surefire has taken a significant step backwards with the KT2 Turbohead, at least from this Flashaholic's point of view. Why did it design the 2.5 turbo to produce a larger, less intense hot spot? Perhaps Surefire has a good reason for this seeming regression.
PK, if you're reading this I assure you that my intent is not to be critical, and you may recall that I have expressed my respect and appreciation of your abilities in other posts. It is simply that I am so disappointed and puzzled by my experience with this product.
Some further observations:
Weight: the KT2 is surprisingly heavy: 4.8oz vs 3.4oz for the 3" turbohead. That seemingly small difference means that the KT2 is 40% heavier than the older unit.
Reflector faceting: when I closely compared the faceting of the US, the KT2 and the 3" T-head I found that the US seemed extremely subtly faceted for approximately the first 40% of its depth near the lamp then becoming non-faceted, and the entire reflector including the faceting appearing very reflective and "shiny". The faceting on the 3" reflector was also subtle, though more obvious than the US, but still shiny enough to reflect recognizable images, such as my hand and other objects. The KT2 was the least reflective of the three, barely able to reflect any recognizable image. Out of curiosity I examined the reflector on my M6. Sure enough, the faceting, though subtle, was almost as reflective as that of the 3" turbo, and distinctly more so than the KT2.
There appears to be a proportional relationship between faceting reflectivity or "shinyness" and brightness and focus. Of course it's more complex than that, with the size, angle and density of the facets along with reflector shape and size being critical factors. But to this layman's eyes a bright, reflective barely faceted reflector = a bright focused light.
As a result of my experience with the KT2, I don't plan on ordering any more turboheads from Surefire, unless CPF colleagues feel that a particular combination is especially competent.
Also, I'm now even more skeptical toward LPS' claim of a "compact turbohead, less than 2.5" in diameter". I hope I'm wrong because to have a 3x123 turbohead Surefire with N2 lamp for one hour burn that not only matches the US, but does so with a small diameter head would be a dream come true
In my perhaps simplistic view the whole point of a turbohead is to throw an intensely concentrated beam of light as hard and far as possible. Judged by those criteria, I'm sorry to say that in my opinion the KT2 falls short.
Brightnorm
.
I just received my KT2 lamp/reflector kit with N2 lamp for my 9P SF. My first impression as I removed it from the box was positive. It had a ruggedly stylish look that was very appealing. It was also more compact than my "classic" 3" Turbohead that I bought for my old 6P years ago: 2.5" diameter and 2.5" length vs 3" and 3" length. It also seemed heavier than the larger and older T-head, but I ignored that in my eagerness to try it.
After I attached it to my 9P and ignited it my heart sank. The beam seemed surprisingly large in diameter and lacking in intensity. I thought that my judgment was perhaps subjective and inaccurate so I got out my 6P with the old 3" turbo and compared the two beams.
The beam from the 6P 3" turbo was about 40-50% smaller than that of the 9P + N2. It was nearly perfectly round with almost no corona so that the light was nearly 95% hotspot. Consequently, it was actually brighter than the larger light even though there was "more" light coming from the 9P. To say that I was disappointed would be an understatement.
Next, I compared them both to my tightly focused US. No contest! Neither Surefire matched the Streamlight, whose beam was only slightly larger than the3" turbo's.
Finally, I put the N2 into the 3" turbohead and attached it to the 9P. Now THERE was a light! The beam was about the same diameter and focus as the US, perhaps a little cleaner with less coronal spread and nearly identically bright.
Now I had a light that was just as bright and penetrating as the US, but much smaller, lighter and easier to carry. Look at the specs:
UltraStinger - L: 11 5/8" Wt: 1lb + 3/10 oz
SF 9P with 3"turbo - L: 8" Wt: 9.5oz
To put it another way, the SF 9P with N2 in that "old, outmoded turbo" provided equivalent performance to the US which is 45% longer and 70% heavier and much more cumbersome to carry. The only negative is the 3" diameter.
It appears that Surefire has taken a significant step backwards with the KT2 Turbohead, at least from this Flashaholic's point of view. Why did it design the 2.5 turbo to produce a larger, less intense hot spot? Perhaps Surefire has a good reason for this seeming regression.
PK, if you're reading this I assure you that my intent is not to be critical, and you may recall that I have expressed my respect and appreciation of your abilities in other posts. It is simply that I am so disappointed and puzzled by my experience with this product.
Some further observations:
Weight: the KT2 is surprisingly heavy: 4.8oz vs 3.4oz for the 3" turbohead. That seemingly small difference means that the KT2 is 40% heavier than the older unit.
Reflector faceting: when I closely compared the faceting of the US, the KT2 and the 3" T-head I found that the US seemed extremely subtly faceted for approximately the first 40% of its depth near the lamp then becoming non-faceted, and the entire reflector including the faceting appearing very reflective and "shiny". The faceting on the 3" reflector was also subtle, though more obvious than the US, but still shiny enough to reflect recognizable images, such as my hand and other objects. The KT2 was the least reflective of the three, barely able to reflect any recognizable image. Out of curiosity I examined the reflector on my M6. Sure enough, the faceting, though subtle, was almost as reflective as that of the 3" turbo, and distinctly more so than the KT2.
There appears to be a proportional relationship between faceting reflectivity or "shinyness" and brightness and focus. Of course it's more complex than that, with the size, angle and density of the facets along with reflector shape and size being critical factors. But to this layman's eyes a bright, reflective barely faceted reflector = a bright focused light.
As a result of my experience with the KT2, I don't plan on ordering any more turboheads from Surefire, unless CPF colleagues feel that a particular combination is especially competent.
Also, I'm now even more skeptical toward LPS' claim of a "compact turbohead, less than 2.5" in diameter". I hope I'm wrong because to have a 3x123 turbohead Surefire with N2 lamp for one hour burn that not only matches the US, but does so with a small diameter head would be a dream come true
In my perhaps simplistic view the whole point of a turbohead is to throw an intensely concentrated beam of light as hard and far as possible. Judged by those criteria, I'm sorry to say that in my opinion the KT2 falls short.
Brightnorm
.
