I just picked up a new data logging light meter and I have been fascinated with Quickbeam's and Selfbuilt's tests and their ability to test output over time..........so I finally made the plunge. I give them credit for steering me into the milk carton light box setup and graphing the data in Excel.
I tested some of the lights I have and it was fun to see which lights have the most linear output along with efficient drivers. This helps me decide which ones are keepers and which ones I give away or sell.
As for the milk carton lightbox.......I cut off the top and made a lid which I then glued a white piece of poster board to the inside. That way I could get into the box if I needed. I also made the main hole equivalent to the diameter of my biggest light........a Mag D. Then I cut out little white card stock covers with holes to match the various lights I have. That way I could keep all the light in the box and make the test very repeatable.
Also I made a 9v linear power supply to power the meter so I didn't have to worry about going through batteries for the many long runs. These are the Lights that I tested. I'm mostly an AA and AAA Eneloop guy. All lights were tested with freshly charged Eneloops.
Romisen RC-N3 II, XP-G R4
Olight T25T, XP-G R5
iTP SA2, XP-G R5
Streamlight 4AA PP
MiniMag Terralux driver w/ SSC P4
Romisen RC-G2 II, XP-G R4
Zebralight H501
iTP A3 EOS, Q5
I still need to test my Streamlight Microstream and PT EOS P4 modified headlamp. I'll update later. As far as the numbers on the left of the graph, that is the Lux reading from the meter. Not sure how to equate that into lumens. I just use it as a relative comparison.
I found the Olight T25T and iTP SA2 to be the most efficient and linear lights I have. Underneath the graphs I did some calculations to figure out which lights preformed the best. In addition to LED color tint and beam pattern, I've always been interested in the lights that can hold constant output til the batteries are almost used up. I love seeing those straight lines. Basically, efficiency in brightness over the run is the area under the curve. A light that is half as bright should last twice as long right?
Remember when the Streamlight 4AA Propolymer was such a popular light? That was my first LED light. Now that light is near the bottom in performance especially considering the fact that it has 4 batteries. Also of note is the Romisen RC-N3 II, two mode light. The lower setting isn't very efficient at all. And so it makes no sense to even have that function in my opinion. In Low mode, if the brightness was going to be half of HI mode, then I would expect the run time to be at least twice as long as it was on HI. I love the price and the R4 tint though.
It's these characteristics that you'd never Know existed unless you tested against other similar lights.
I tested some of the lights I have and it was fun to see which lights have the most linear output along with efficient drivers. This helps me decide which ones are keepers and which ones I give away or sell.
As for the milk carton lightbox.......I cut off the top and made a lid which I then glued a white piece of poster board to the inside. That way I could get into the box if I needed. I also made the main hole equivalent to the diameter of my biggest light........a Mag D. Then I cut out little white card stock covers with holes to match the various lights I have. That way I could keep all the light in the box and make the test very repeatable.
Also I made a 9v linear power supply to power the meter so I didn't have to worry about going through batteries for the many long runs. These are the Lights that I tested. I'm mostly an AA and AAA Eneloop guy. All lights were tested with freshly charged Eneloops.
Romisen RC-N3 II, XP-G R4
Olight T25T, XP-G R5
iTP SA2, XP-G R5
Streamlight 4AA PP
MiniMag Terralux driver w/ SSC P4
Romisen RC-G2 II, XP-G R4
Zebralight H501
iTP A3 EOS, Q5
I still need to test my Streamlight Microstream and PT EOS P4 modified headlamp. I'll update later. As far as the numbers on the left of the graph, that is the Lux reading from the meter. Not sure how to equate that into lumens. I just use it as a relative comparison.
I found the Olight T25T and iTP SA2 to be the most efficient and linear lights I have. Underneath the graphs I did some calculations to figure out which lights preformed the best. In addition to LED color tint and beam pattern, I've always been interested in the lights that can hold constant output til the batteries are almost used up. I love seeing those straight lines. Basically, efficiency in brightness over the run is the area under the curve. A light that is half as bright should last twice as long right?
Remember when the Streamlight 4AA Propolymer was such a popular light? That was my first LED light. Now that light is near the bottom in performance especially considering the fact that it has 4 batteries. Also of note is the Romisen RC-N3 II, two mode light. The lower setting isn't very efficient at all. And so it makes no sense to even have that function in my opinion. In Low mode, if the brightness was going to be half of HI mode, then I would expect the run time to be at least twice as long as it was on HI. I love the price and the R4 tint though.
It's these characteristics that you'd never Know existed unless you tested against other similar lights.