Measuring light output with an integrating sphere

[@peturstefansson]

Looking forward to see some results.

[@Lumencraft-]

Great video. May I ask where you got the cheaper of the 2 calibration bulbs?

[@kepa109]

AdventureSportFlashlights... I love your videos!!!!

[@wzukr]

Would like to see some results. Need a new light for my MTB used in low level mountains, mixed forest and open space. Costs max. 130 US-$. Any recommendations?

[@alanhowitzer]

I was wondering what mountain bikes had to do with lighting.

[@spiritresonancejv]

I need some light testing done. please contact me

[@briansamphs3720]

I though this dude was wearing camouflage for about the first half of the video

[@broderp]

There has to be a cheaper version of this for hobbyist who just want to do light comparisons for such things as car LED headlights....

[@JasonWW2000]

broderp - For comparisons, where you don't need to know the actual lumens, then you could definitely make a homemade tester. Take an old styrofoam cooler and cut a hole in one side to mount an inexpensive lux meter and then put your bulb into a hole on the opposite side. Then add a white shield a couple of inches in front of the Lux meter to stop direct light hitting it. As long as you put your test bulbs in the same location firing in the same basic direction you should get consistent readings to help you compare them.

[@chrispompano]

@@JasonWW2000 .....exactly what I want to do also. I wish someone would do a video on how to set it up. I want to compare a few low output signal incandescent automotive bulbs and some similar LED's....is this sort of what you're talking about like what this guy did? kzbin.info/www/bejne/qHycm2l9mNKLi8U Any suggestions on a reasonable priced light meter that can also measure the bulb-color temp?

[@JasonWW2000]

@@chrispompano I don't think there's any cheap way to measure the color temperature. Those types of meters are quite expensive. Are you wanting to measure headlight bulbs or side marker type of bulbs? For measuring headlight bulbs I keep things pretty simple. I put my light meter directly to the side of the bulb at a specific distance away, say 18". It's just an arbitrary number, the important thing is to be consistent with all tests. Then I will measure the incandescent bulb intensity (this is not lumens). Then I'll measure the LED bulb where the side LEDs are aimed at the light meter. I believe measuring output 90 degrees from the bulb is going to be the most realistic since that is what shines to the left and right and hits the reflector. In my tests, the better LED bulbs we're about three times the brightness as the incandescent. Making sure the LED headlight bulb gets a good focus from the reflector is a whole other subject. If you're trying to compare the brightness of turn signal bulbs or running light bulbs then it is a very different situation. If the bulb is using a reflector then it's important that the light output be directed towards that reflector so that you get a lot of surface area lit up. If it's a bulb that does not use a reflector then you need to make sure the LED output is sufficiently lighting up the same area very similar to the incandescent bulb. My car and my motorcycle both use a combination of LED and incandescent. They both have LED headlights and brake lights, but all the turn signals and running lights are still incandescent. This is fine as far as I'm concerned because I can see a lot better with the headlight conversion and the brake lights activate much quicker then before. The other lights I don't really care about, they do their job just fine.

[@chrispompano]

@@JasonWW2000 Thanks for that great info. What I'm trying to do is compare a few automotive signal incandescent bulbs to each other ranging from 40-60cp to compare brightness either thru some kind of test-bench, and also installed in the reflector. Also, I want to get the temperature/color measurement of an O.E. style "Amber" colored incandescent bulb of around 32cp, and try to duplicate that same color on another brighter output clear bulb with some different types of amber dyes/paint to be sure I get the correct amber color/temperature while also limiting the amount of coats of dye/paint applied to these clear bulbs to achieve the correct color. I'm trying to make a brighter incandescent turn signal bulb, but also want to test the ZEVO's and Philips Vision's output against the incandescent bulbs as a comparison. I've seen many LUX meters on Amazon, with color temperature, but not sure if they'll work. I also wonder if my Cannon Rebel DSLR can do this, but it only has a color-graph with no actual color-temp numbers...... Any other suggestions are greatly appreciated.

[@JasonWW2000]

@@chrispompano That sounds like an incredibly difficult thing to test for due to all the different factors. The test that comes to my mind is to setup a camera with fixed exposure, tint, etc in a room with a fixed amount of ambient light and take a picture. Then compare the pictures side by side to see the brightness, color and light distribution. The exact color should not matter as long as its close. I've seen different incandescent bulbs be slightly different shades of amber (which is why I tend to replace them in pairs so they match up perfectly). I would not attempt to paint the bulbs because they get so hot that the paint will probably peel off and not last. Personally, I've found that when it comes to turn signal bulbs you want to focus on the surface area and not so much the brightness. A really bright bulb that lights up a small surface area it's not going to be as good as a dimmer bulb that lights up a larger surface area. Especially in the daytime where it's hardest to see. Surface area is key. I see a lot of people replacing their turn signals on their motorcycle with smaller aftermarket units that are brighter, but have less surface area. This makes them very hard to see even though they are brighter. The bigger OEM style turn signals may not look as cool as the smaller, brighter aftermarket signals, but they usually function much better due to the larger surface area and reflectors behind the bulb. I bought a used motorcycle where someone had installed aftermarket turn signals and they looked cool but they were hard to see especially in the day. After nearly getting hit due to drivers not able to see my signals I decided to replace them with some of the nicest looking OEM style units I could find. I never did any scientific comparison between the two, but just standing and looking at them from a distance in bright sunlight the difference was obvious. It's also important to have that big jump in brightness between the running light and the signal light when they blink. Typically it's about a 10x increase in output. You're not going to get the big contrast if it's the same LED that is getting dimmer and brighter. You really want a bulb with two separate LEDs to get the big difference in brightness. The Zevo is what I use for brake lights. It uses two separate LEDs in order to get a big difference in brightness.