UF-1504, 1503, 1505 - multiple LED's tested for throw (just what you have been waiting for!!!)

I did some tests on luxmeters that I posted here on BLF last year. The tests were all within my limited hobby possibilities at home, but perhaps nice to read too? The conclusions were quite like the tests in your link.

Your test is the reason I own the CT1330B.

n10sivern

So I put an S4 2B in a 1405 with a 5 amp driver, dedomed, with a collar and measured 470kcd. I’m confident now that the difference between our numbers is due to the meters. I’m willing to put together a light with a battery and charger and pass it along to a few select members so we can get some baseline numbers so we can compare our results accurately. I have a 1504 with an XP-G2 and no collar that would be a good candidate.

Each person would be responsible for shipping it on to the next.

I have been thinking about this idea of yours KKW, and what if we would take it to the next level :wink:

What if BLF had a light with a CW, NW & WW led in different pills for example a 1504, and we all sent it around to calibrate our lightmeters. Then we should be able to devise a BLF lux & basically be able to use very cheap meters but calibrated to the official BLF conversion factor, that is this light.
Someone could even sell “pre calibrated” already checked conversion factor lightmeters.

I am not sure how the maths would work, but i think it should be possible.

It’s been talked about before, I think the problem is usually too much interest. I like the idea of multiple pills.

I’d probably limit it to about 6 people with a goal of about a month. I hope n10sivern is interested, and I’d like djozz to be in on it, but shipping to Amsterdam might be cost and time prohibitive. I think anyone with multiple meters and a history of doing testing here would be my first choice for candidates beyond that.

I’ll start a new thread to organize this.

I’m game. Just need time to build things and for some LED’s to arrive. I have 2 meters to test.

Interesting, i think the difference between photopic & scotopic is a big reason why, CW light looks more impressive than a NW or WW led, when dedomed & when playing with throwers outside in the dark.

On flooders & throwers i LIKE the look of a nice NW tint the most, BUT in throwers the more CW led i use the stronger it looks somehow even when it is a a similar amp, i had attributed this to thinner phosphors letting out a tiny bit of extra light, but it is most likely very much the difference between photopic & scotopic vision response & that’s why the colder light FEELS more intense.
And i can’t imagine wanting to build a triple or quad with CW leds, that wall of 3000-4500 lumens blue harsh light :Sp urgh……but a nice 3D NW in the same lumens range is just so nice :heart_eyes:

So i have noticed that i chose colder led’s more & more in my thrower build because they feels more (and because i hope to play with RA’s soon), even though i don’t really like CW tints because they are harsh.

But then when dedomed you lose the worst of the blueness of the CW tints, it is going to be interesting to see if i like the XP-L HI 1A already dedomed CW or if that is just to much of a good (intense) thing :wink:

I have ordered stuff for a similar idea: I will make 6 constant output flashlights (with 2x7135 drivers) that are small zoomies with about 25kcd throw. I will thoroughly measure output with my integrating sphere and throw with my top quality luxmeter, and then sell them for cost price to BLF members who do light measurements and are interested. The costs are 12 dollars for the light plus shipping (=a few dollars).

This way, even if my numbers are not trusted (my 'djozz-lumen' is probably close but still has no absolute calibration, my class A luxmeter is top quality but last officially calibrated in 2008), there are six lights around with the same calibration.

Do you have any idea if calibrating with a lower output light like that would be better, worse, or no different than calibrating with a higher output light? I’m not familiar enough with the specifics of how they measure to know if they’re going to be the same percentage off through their whole measurement range. I don’t measure many 25kcd lights, but I measure a lot at 100-500kcd.

Sure it is not ideal, but in my limited experience with the luxmeters I own, lineairity was very good, also with cheap chinese ones, so I think that you get away fine with calibrating with a lower output light

I make lower output reference lights because it is much easier to get the output very constant (less problems with heat sag and varying battery sag). It is way cheaper too, the host is cheaper and because of the small size I can send it as a 'letter box' package, which is 3 dollar worldwide instead of 12+.

Here’s a poor picture of the above mentioned 1405 hitting some low cloud cover. This thing is awesome. I’m going to try the lens I have with a shorter focal length and see if the throw changes at all, I’m hoping it doesn’t go down, I can’t remember what effect it had on the one it’s on now.

Nice work. There shouldn't be a significant vF difference between different XP-L bins, but there is a difference between production batches, and I wouldn't be surprised to see the vF go up and them become more fragile like the XM-L2s have.

I always struggle with requests to publish throw and lumen numbers, because I know that my meters are not accurate. They are a good comparison tool, but if someone "took me to court" to verify the accuracy of the numbers, there is no way they would hold up. I use them far more to compare with my own stuff (e.g. before and after mod. measurements), but I don't trust them at all to compare against others results. I know some guys who have the same or similar built lights who measure significantly higher than I do and others that measure significantly lower.

Just my 2c, but I don't get too caught up in comparing with others because must of us have level measuring equipment and use inconsistent measuring methodologies. It's fun to compare, but I don't get too wound up with the inconsistencies. The only way to get comparable numbers would be to measure the lights back-to-back, same day, same place, same meter. I'm not saying that the different data points from everyone aren't valuable--because they are, but don't get too hung up on expecting your measurements to be identical to others' measurements.

Nice beamshot KKW :slight_smile:

I am surprised we haven’t seen more hotrodded 1405/1504 beamshots, they look great when maxed out, especially when there is lots of moisture in the air like all throwers :wink:

I'm out camping right now, but did not bring the 1405. I did bring the shortened 1406 and will do a beamshot tonight :-)

How nice to be out camping :slight_smile: and i see you guys in Holland have gotten summer already, here in Sweden it is still ways off and it is almost June :frowning:

19degC and sunny all day, group camping with a couple of families, drinking coffe and beer and bbq+camp fire at night :bigsmile:

A bit blurry but here's a bbq-beamshot with the 1406-shorty :-) :

https://farm6.staticflickr.com/5344/17866863200_55e2ba4015_b.jpg

(sorry, can't get the photo into the editor on my phone)

Thanks pd68, one more then, 230kcd in J.'s face (eyes closed btw ;-) ) :

I will fix the image tomorrow.

Again remember that although you can calibrate different meters from the same LEDs placed in a host, the argument against many meters is that they are highly spectral dependent. The moment that one new tint (basically any different LED) enters the group, the calibration is once again reset to being in an unknown relation to it. An LED’s true lumen rating is going to be based on an average curve of light energy that is a result of a combination of colors, but like a CFL bulb, they have spectra falling “all over the place” you might say. The optimum way to do it, would be to purchase 1 single JETI Specbos 1211 reference spectroradiometer, and then the lights are sent to the holder of that unit for testing. In other words, your throne seat here costs about $8500.

I would like to have this one tested: