Opple Light Master III (G3) discussion thread (Cheap device for measuring Lux, CCT + CRI)

Thank you very much!

I will test your modified app if I get a LM4 in the next weeks. Did you test the modified apps with LM3/LM4?

I myself didn’t (my LM4 still hasn’t arrived), but I asked other people to check out the LM4 mods and they confirmed they see all the measurements fine.
I also don’t own an LM3, but I’m sure that the Pro mod should work as well since I didn’t touch anything that might’ve broken it.

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I’ll have to interject again.

To me, what you describe strongly suggests the collection of personal data (or metadata, which is basically enough for user profiles), or at least that this is being negligently accepted. With the best will in the world, I can’t imagine that an app for smart homes needs so many different services and APIs. Tencent and Baidu in particular - what for? In my opinion, only two components are needed to control various smart home components and bug tracking: the API to Opple and to the bug tracker (although in principle this could also run directly via Opple’s API). And extended functions for integrating other services could be designed as opt-ins and additional modules, although I’m not familiar enough with this topic. Either way, I don’t see any problems in designing the app in a data-saving and data protection-compliant way.

I don’t want to accuse Opple of anything, but it’s funny, especially if you look around at what’s going on in Chinese apps. For me, “smart home” is a data protection nightmare anyway, and I distrust every provider in this respect, not just those from China.

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I reinstalled old version Intel driver from 2015, now I get this reported by radex, no more 20/30hz nonsense.

There is still some temporal dithering confirmed with high speed camera.

Price gouging with Opple LM3 now that LM4 has fallen. LOL $140 :exploding_head: on AliExpress HERE

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wow, major price gouge on indeed!

otoh, the Opple 4 is now down to $25, and it works fine with High CRI LEDs, and gives almost identical results as Opple 3.

They both go bananas on Low CRI LEDs… Neither is a science grade instrument, but either is better than nothing, for comparing my own lights to each other, and before and after an LED swap.

Neither is as accurate as a ColorMunki, or other more expensive tool.

Imo the Opple 4 is fine for a home hobby use, just dont expect it to be completely accurate compared to more expensive spectrophotometers.

and fwiw, accuracy is overrated. LEDs vary so much from one to another, that it makes no difference how accurate the spectrometer is… Any values someone gets with their LED will be different with any other LED, even from the same reel and bin and batch, even when using very expensive spectrometers.

For me the key to understand about the LM3 is that even though it is obviously an amateur grade device, I have observed in both my LM3’s that it is CONSISTENT in its behavior. If a unit reads Duv 20 points too positive, it tends to do that in all the LED’s in my own experience. And more importantly the numbers are consistent/repeatable.

The two LM3’s that I have actually show very good accuracy for such a cheap device. My 219b reads minus 80-100 consistently, and 519a 4500k reads 0.0000 consistently. So when I see GT-FC40 at minus 40, I know right away it’s going to look in between. It’s a GREAT amateur device to use together with our own white walling observation.

Had I known about the debacle that is LM4, I probably would have bought one more LM3 in case these break. In retrospect LM3 is such a bargain and if anyone has one, congratulations. Too bad re. the price gouging. But it is tempting. :innocent:

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very glad youre enjoying your LM3, I still use mine regularly.

I also have LM4, but seldom use it.

my LM3 and LM4 produce almost identical results, with some LEDs. It seems the LM4 agrees most with LM3 when testing 4500K High CRI

they differ, and the amount of difference changes at other CCT of High CRI. When testing Low CRI the differences are so large as to make me not trust the accuracy of neither LM3, nor LM4.

I dont have any other spectrophotometers, so I dont know what the LM3 or LM4 “variation in calibration” is, compared to a more accurate meter.

But using either LM3 or LM4, I can definitely see large variations between individual LEDs of mine.

For example, here are two DeDomed 4500K 519a. The came from the same batch, bin, and reel, infact they were side by side in the tape. Both LEDs measured on the same LM3, at the same Lumens:

There is a difference of -0.0043, between the two LED samples. Irrespective of the actual calibration error of the LM3.

Individual LED variation can be pretty significant, totally independent from whether the LM3 is actually calibrated to the same zero as a more accurate meter. There are also variations in DUV at different Lumen levels

Point being, accuracy expectations can be unrealistic, when comparing tests of different individual LED samples…

There is so much variation between individual LEDs, that even with totally accurate meters, any DUV test I report from an LED of mine, is guaranteed to be different than an LED of yours.

Despite all those sources of variation, an LM3 or LM4 can be a handy tool for comparing our own LEDs to each other.

I also really like the Flicker Index function of both the LM3 and LM4. fwiw, both meters produce very similar results when testing Flicker Freqency and PWM.

Bottom line, though I prefer my LM3, I dont hesitate to recommend the LM4 at this time. The price is right and it can be an informative tool.

The LED binning MacAdam-Ellipses have the size of “a human can’t differentiate a color variation” so it should be OK. But it would be interesting how consistent LEDs from one batch read with a good colormeter.

Here is German page about binning in google translate

This lil sh** stoped connecting to Pixel 6a phone properly. Photometry Start button gone, but flicker option works. No problems with old Samsung S5. Any sugestions?