brightnorm
Flashaholic
- Joined
- Oct 13, 2001
- Messages
- 7,160
A Major step Forward: LPS\' new Compact Turbohead for SUREFIRES
In the thread "Surefire Turbohead Disappoints" I expressed my surprise and disappointment with what seemed to be less than ideal performance of my D3 using the 2.5" KT2 turbohead, especially when compared to my old 3" (T1/T2) turbo. There were many responding posts including Ken J. Good who said:
"I have told folks for years that this (the 3" turboheads" ) was the hidden treasure of the SureFire product line. Not too many believed." Well Ken, now they do.
When LPS recently announced their "New Compact Hybrid Turbo-Head D3" the SRD3 (The SRTH is the Turbohead and LA assembly alone, without the D3), after my experience with the KT2 I was skeptical, to say the least, but since it's not fair to prejudge a product, especially one from a usually reputable source I decided to buy one and comparison test it. I apologize to my Flashaholic colleagues for my lack of a digital camera.
Tests were conducted 20 Feet from a smooth white surface using a fully charged Ultrastinger and a SF D3 with N2 105 Lumen lamp. Fresh Surefire 123's were postdated 2011. Observations were non-instrumented except for the use of a tape measure. Two (non-Flashaholic) witnesses attended. Agreement on the following figures was generally unanimous, with minor differences.
BRIGHTNESS ("INTENSITY" (Subjective visual rating)
10 ---Ultrastinger
9.7 ---3" T1/2 Turbo
8.9 ---2.5" LPS "Compact Turbo"
6 ---2.5" KT2 turbo
"HOTSPOT" DIAMETER at 20'
16" ---Ultrastinger
16" ---3" T1/2 Turbo
21" ---2.5" LPS "Compact Turbo"
30" ---2.5" KT2 Turbo
TOTAL DIAMETER ("HOTSPOT" PLUS "CORONA" at 20'
48" ---Ultrastinger
25– 40" ---3" T1/2 Turbo
35" ---2.5" LPS "Compact Turbo"
48" ---2.5" KT2 Turbo
COMMENTS
To begin with, these non-instrumented measurements are all subject to some degree of error. Also, they will almost certainly vary from one supposedly "identical" turbohead to the next (as we saw with a borrowed 3 incher that gave us results midway between our 3" sample and the compact 2.5" . Even with Surefire's excellent close-tolerance manufacturing, the very slightest deviation of either reflector curvature or reflector/filament relationship or both will cause a visible beam variation especially when magnified by even a short projected distance.
ULTRASTINGER:
Truly a magnificent light, we used it as our standard, giving it a rating of 10 (or 100%) for purposes of this test. There are some people who might nitpick about "subtle shadows in the beam", but those objections would most likely not be relevant in practical use.
3" T1/2 TURBO (WITH N2):
Virtually equal to the US. We marked it down by .3 because of its uneven somewhat "wispy" corona, which subtracted very slightly from the total projected light. Nevertheless, for all practical purposes the two lights can be considered equal, although the US will maintain brightness longer than the SF.
NOTE: Of the four lights tested only the US and the 3" T1/2 + N2 had distinctly delineated hotspots.
This made measuring much easier and seems to have accounted for, or been a manifestation of, their superior performance. The designation "T1/2" refers to the fact that there is only one 3" turbo, called the T1 with the NT lamp, and the T2 with the HOLA.
LPS COMPACT 2.5" TURBO:
Although not quite the equal of the US or the 3" Turbo in brightness or throw, we considered the LPS a success because of its marked superiority to the KT2 2.5" Turbo and its very decent showing against its intimidating competitors. LPS' claims of excellence were vindicated, and their statement: 'smaller than 2.5" ' turned out to be true. Even though the diameter of the two units was the same, the shape of the LPS was considerably less bulky than the KT2, and it weighed more than 40% less: 2.7oz vs. 4.7oz. Put another way, the KT2 weighed 75% more than the LPS.
2.5" KT2 TURBO
It is possible that this unit may be excellent for "professional" use. As a civilian I am not qualified to judge. However, I was so disappointed when I first tested this unit that I felt compelled to post my reactions (See thread: "Surefire Turbohead Disappoints). In spite of this, the KT2's projected beam is very smooth and quite round, a really lovely looking beam, but quite diffuse and simply not as bright as the others.
NOTE: Any apparent inconsistencies between the brightness and diameter charts are accounted for by subtle variations in corona brightness and shape, as well as the percentage of total light that is presented in the corona, in addition to how suddenly or gradually the hotspot merges into the corona. For purposes of this test, the term "corona" refers to the dimmer "doughnut" of light surrounding and immediately adjacent to the "hotspot". Sometimes the corona is easily seen and measured, other times it almost defies clear perception or measurement. I would use the term "Peripheral" light to represent the "Corona that surrounds the Corona" Clearly, these tests cry out for instrumentation, or at least beam pics.
BEAM PROJECTION ("THROW" TESTS):
These are very difficult to conduct in my city, especially in my neighborhood where people are bustling about until late at night, and where projection tests are best done vertically (up the sides of tall buildings) because open, dark horizontal space is so hard to come by. The large local park remains a possibility, but I don't wish to add mugging to the list of difficulties involved in this kind of testing.
I was able to do a rather crude "vertical throw" test (mentioned in that other thread) using the D3 with T2 3" Turbo and I might be able to similarly test the other Turbos eventually, but that is probably unnecessary. We know that the US and the T2 are essentially equal, and that the LPS is a fairly aggressive competitor, just as we have seen that the KT2 is the weakest of the four,
It is possible however, that real life distance testing might yield unexpected results and I invite my colleagues who live in less congested areas to see what they can come up with.
Two remaining points:
TYPE OF REFLECTOR FACETING: The points made in the previous thread continue to prove true.
MN16: I have one on order, but I'll test it only in my 3" because I have lost interest in and will be returning the KT2, and Wayne of LPS believes that their compact unit is best served by the N2.
This is a good place to mention that the service and level of customer care recently provided by Wayne and LPS was superb, definitely beyond the call of duty.
I hope this Lonnnnnnggg report enlightens more than it obfuscates!
Best regards,
Brightnorm
In the thread "Surefire Turbohead Disappoints" I expressed my surprise and disappointment with what seemed to be less than ideal performance of my D3 using the 2.5" KT2 turbohead, especially when compared to my old 3" (T1/T2) turbo. There were many responding posts including Ken J. Good who said:
"I have told folks for years that this (the 3" turboheads" ) was the hidden treasure of the SureFire product line. Not too many believed." Well Ken, now they do.
When LPS recently announced their "New Compact Hybrid Turbo-Head D3" the SRD3 (The SRTH is the Turbohead and LA assembly alone, without the D3), after my experience with the KT2 I was skeptical, to say the least, but since it's not fair to prejudge a product, especially one from a usually reputable source I decided to buy one and comparison test it. I apologize to my Flashaholic colleagues for my lack of a digital camera.
Tests were conducted 20 Feet from a smooth white surface using a fully charged Ultrastinger and a SF D3 with N2 105 Lumen lamp. Fresh Surefire 123's were postdated 2011. Observations were non-instrumented except for the use of a tape measure. Two (non-Flashaholic) witnesses attended. Agreement on the following figures was generally unanimous, with minor differences.
BRIGHTNESS ("INTENSITY" (Subjective visual rating)
10 ---Ultrastinger
9.7 ---3" T1/2 Turbo
8.9 ---2.5" LPS "Compact Turbo"
6 ---2.5" KT2 turbo
"HOTSPOT" DIAMETER at 20'
16" ---Ultrastinger
16" ---3" T1/2 Turbo
21" ---2.5" LPS "Compact Turbo"
30" ---2.5" KT2 Turbo
TOTAL DIAMETER ("HOTSPOT" PLUS "CORONA" at 20'
48" ---Ultrastinger
25– 40" ---3" T1/2 Turbo
35" ---2.5" LPS "Compact Turbo"
48" ---2.5" KT2 Turbo
COMMENTS
To begin with, these non-instrumented measurements are all subject to some degree of error. Also, they will almost certainly vary from one supposedly "identical" turbohead to the next (as we saw with a borrowed 3 incher that gave us results midway between our 3" sample and the compact 2.5" . Even with Surefire's excellent close-tolerance manufacturing, the very slightest deviation of either reflector curvature or reflector/filament relationship or both will cause a visible beam variation especially when magnified by even a short projected distance.
ULTRASTINGER:
Truly a magnificent light, we used it as our standard, giving it a rating of 10 (or 100%) for purposes of this test. There are some people who might nitpick about "subtle shadows in the beam", but those objections would most likely not be relevant in practical use.
3" T1/2 TURBO (WITH N2):
Virtually equal to the US. We marked it down by .3 because of its uneven somewhat "wispy" corona, which subtracted very slightly from the total projected light. Nevertheless, for all practical purposes the two lights can be considered equal, although the US will maintain brightness longer than the SF.
NOTE: Of the four lights tested only the US and the 3" T1/2 + N2 had distinctly delineated hotspots.
This made measuring much easier and seems to have accounted for, or been a manifestation of, their superior performance. The designation "T1/2" refers to the fact that there is only one 3" turbo, called the T1 with the NT lamp, and the T2 with the HOLA.
LPS COMPACT 2.5" TURBO:
Although not quite the equal of the US or the 3" Turbo in brightness or throw, we considered the LPS a success because of its marked superiority to the KT2 2.5" Turbo and its very decent showing against its intimidating competitors. LPS' claims of excellence were vindicated, and their statement: 'smaller than 2.5" ' turned out to be true. Even though the diameter of the two units was the same, the shape of the LPS was considerably less bulky than the KT2, and it weighed more than 40% less: 2.7oz vs. 4.7oz. Put another way, the KT2 weighed 75% more than the LPS.
2.5" KT2 TURBO
It is possible that this unit may be excellent for "professional" use. As a civilian I am not qualified to judge. However, I was so disappointed when I first tested this unit that I felt compelled to post my reactions (See thread: "Surefire Turbohead Disappoints). In spite of this, the KT2's projected beam is very smooth and quite round, a really lovely looking beam, but quite diffuse and simply not as bright as the others.
NOTE: Any apparent inconsistencies between the brightness and diameter charts are accounted for by subtle variations in corona brightness and shape, as well as the percentage of total light that is presented in the corona, in addition to how suddenly or gradually the hotspot merges into the corona. For purposes of this test, the term "corona" refers to the dimmer "doughnut" of light surrounding and immediately adjacent to the "hotspot". Sometimes the corona is easily seen and measured, other times it almost defies clear perception or measurement. I would use the term "Peripheral" light to represent the "Corona that surrounds the Corona" Clearly, these tests cry out for instrumentation, or at least beam pics.
BEAM PROJECTION ("THROW" TESTS):
These are very difficult to conduct in my city, especially in my neighborhood where people are bustling about until late at night, and where projection tests are best done vertically (up the sides of tall buildings) because open, dark horizontal space is so hard to come by. The large local park remains a possibility, but I don't wish to add mugging to the list of difficulties involved in this kind of testing.
I was able to do a rather crude "vertical throw" test (mentioned in that other thread) using the D3 with T2 3" Turbo and I might be able to similarly test the other Turbos eventually, but that is probably unnecessary. We know that the US and the T2 are essentially equal, and that the LPS is a fairly aggressive competitor, just as we have seen that the KT2 is the weakest of the four,
It is possible however, that real life distance testing might yield unexpected results and I invite my colleagues who live in less congested areas to see what they can come up with.
Two remaining points:
TYPE OF REFLECTOR FACETING: The points made in the previous thread continue to prove true.
MN16: I have one on order, but I'll test it only in my 3" because I have lost interest in and will be returning the KT2, and Wayne of LPS believes that their compact unit is best served by the N2.
This is a good place to mention that the service and level of customer care recently provided by Wayne and LPS was superb, definitely beyond the call of duty.
I hope this Lonnnnnnggg report enlightens more than it obfuscates!
Best regards,
Brightnorm
