Berezny Your discovery about incandescent/halogen bulbs after the 72W mark no longer flickering is a fascinating tidbit.

I have a question mark about this one.. what happens with 130v bulbs on a 120v circuit? They still consume the same power in watts, but the lumen output is reduced by about 25% due to the voltage difference so a 100w 130v bulb puts out roughly the same amount of brightness as a 75w bulb and I guess a 60w 130v bulb would appear like a 40w 120v bulb. So does the 100w bulb flicker or not when the voltage is different? Looking into it further, maybe I was mistaken about the wattage staying the same.. I read that it also goes down to about 85w but this would need to be tested with an actual meter to measure how much power is consumed at the plug before and after.

With this database, I hope to give you and everyone else, access to the information that these companies don’t seem to want to give us.

1500x30price

IMO the only reason to use this formula is because as you say, sadly it seems to be widely adopted already and could make it easier to compare to some manufacturer's values. But again, for smaller values the differences become increasingly tiny, and no manufacturer is even bothering to print multiple positions after decimal point. So the smallest official value we could compare to is probably a very rough one like "< 1%" anyway.

Maxlite changed the manufacturing process and now the new 60w 2700k bulbs flicker pretty badly. There are a few old, non-flickering ones on eBay. Here’s an eBay listing that has them for about $2 per bulb with shipping. https://www.ebay.com/itm/155900291630

The first thing I did after purchasing the Fauser LiFli flicker detection device was to change its flicker percentage calculation from "/ (max + min)" to "/ max" (it offers this as a feature). Because the lowest percentage on its scale is 2% (which actually means 0% - 1.5%), and if I used "/ max + min", too many light sources would fall into this range. Light sources which when using "/ max" stay well above that range and are ones we probably want to stay away from.

It seems like the main drawback of the Opple LightMaster is that it doesn't have the AC mode (or at least I'm not aware that it does), so you can't zoom in.

There are of course lights that I have not yet tested, such as Yuji’s MaxCRI and Sunwave lineup. They're just so damn expensive…

Here's a screen shot from my setup (photodetector + oscilloscope) on DC mode. It shows pretty much the same thing. Mostly flat with dips at 120hz.

To me it seems "/ (max + min)" was an arbitrary choice to somehow account for the form or area of waves, too (in a very rough way). You can calculate a few test values to realize how (max - min) / (max + min) is producing values even for stronger flicker that are not very helpful for comparison (for example PWM that only goes down half of the amplitude would be equal to 33% flicker, when we'd naturally expect 50%) and how quickly calculation results approximate each other the smaller the flicker gets.

I really like how you can quickly gather the information from the table format. If you measured these all by yourself, which device did you use to do so? From the supplied charts, I assume it's the Opple Light Master 3, since another member here has made a similar website using that device pretty recently.

I’ve spent the last few months putting together a large database of light bulbs (93 as of this moment), basically any of them I could find.

I think we should use (max - min) / max. The reason is that the formula (max - min) / (max + min) is not linear. It produces increasingly less differences the smaller the flicker gets. But we are especially interested in small flicker values, too. So dividing by (max + min) hurts our interest of making even small flicker values reasonably comparable.

As many of you are aware, the lighting industry is currently doing whatever they want with regard to flicker, and worst of all, they can say what they like and we just have to take their word for it.

Hopefully, over time the database will just get larger and larger and maybe we can convince these companies to take their lighting more seriously once their dirty laundry is aired for everyone to see.

1500x30insulation

One interesting thing I discovered is that incandescent/halogen lights completely stop flickering after the 72w mark! Very cool. I thought they all flickered, but apparently not.

Unfortunately I've been inconsistent in my posts. A few weeks ago (including the post above) I was using (range)/(max) which is equivalent to (max-min)/(max). Over the past week or so I've been using (max-min)/(max+min), which seems to be more commonly-used.

KM I think we should use (max - min) / max. The reason is that the formula (max - min) / (max + min) is not linear. It produces increasingly less differences the smaller the flicker gets. But we are especially interested in small flicker values, too. So dividing by (max + min) hurts our interest of making even small flicker values reasonably comparable.

I didn't want to shell out $64 for a two-pack of Yuji bulbs (but if they eliminate my headaches then it would be totally worth it). So I bought the Philips Ultra Definition, 2700K, 1100 lumens 11w bulb.

This is amazing! I sent a small donation in appreciation for the value of this! I dream to find something like this for LED lights used as backlights.

Some of the halogens like the GE 29W Halogen shows 10% flicker at 120Hz which I expect (60 * 2 = 120Hz, for USA electric):

I think I'm extremely sensitive to small amounts of rapid flicker (I think flicker as low as 1% can affect me if there are abrupt changes in brightness). Though I'm not 100% sure about that.

GregAtkinson So the flicker percentage is about 4% (since on DC mode you can see that it's generating a bit more than 600 mv)

GregAtkinson I tried the Maxlite 2700K 60W bulbs a couple weeks ago, but as @GregAtkinson and I expected they might given the spiky shape of the flicker waveform, they made me sick with concussion-like symptoms, although were definitely better than LEDs with high flicker. They were similar to other low-flicker lights that still injure me (data here). These were the MaxLite 2700K A19, E9A19D27/49/WS1, Code 14099718. So maybe they have the new, worse engineering? These had 0.17% flicker (calculated in the standard, misleading way used by the lighting industry).

Your discovery about incandescent/halogen bulbs after the 72W mark no longer flickering is a fascinating tidbit. I bet that kind of data is exactly what lighting enthusiasts and professionals are looking for but struggle to find, especially those in part time electrical jobs. Will your database be accessible to the public soon? I imagine a lot of folks would love to dive into the data.

However, on AC mode you can really see how much it flickers. Its range is 25 mv (goes up to almost 10 mv and down to a bit more than -15 mv).

So the flicker percentage is about 4% (since on DC mode you can see that it's generating a bit more than 600 mv). And the drops are pretty sharp/jagged, indicating abrupt changes in light output.

I bought about 150 bulbs from various sellers that will hopefully last until my kids put me in a nursing home. It’s a large box, but still a very poignant reminder of my limited time on earth.

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