Similar to @Limsup, I’ve found for lights with high CRI and negative Duv, the LM4 makes the reading less negative. For example Nichia 219b which typically reads -0.0100 in my LM3, would read -0.0050 in my LM4.
OTOH with low CRI lights with positive Duv, my testing so far found the opposite. Duv becomes less positive. In my Wurkkos TS30S with SBT90.2 for example, at lower brightness, Duv which is about 0.0040 in LM3 would read 0.0020 in LM4, and at Turbo-level brightness, 0.0010 with LM3 would read even negative 0.0010 in LM4. And this SBT90.2 LED is known to have a strong green tint, so LM4’s negative reading is obviously “quite” wrong.
This is my setup. When the going gets serious , I put light on tripod and mark where the hot spot is. Nearly all LEDs change Duv with less brightness from step-downs, so I have active cooling to keep brightness stable.
@stevechang
What about if we orginised a group buy for a LM5? Would your company be interested? Not sure how many we could sell but I think BLF members would be interested? Make an open-source android app.
thank you for your proposal, I am moved.
after a 5.5 years stint at opple, yes, I am determined to leave opple now.
I hope opple can financially do well in the future, in that case perhaps LM project would be restarted. and perhaps I would return and continue to develop LM.
I hope opple all the best in the future.
Big thank you to @Cod3r for providing a modified version of the app without need for login or internet. I was not able to get it to work with any of the official apps, but with Cod3r’s app I got my LM4 running again, better than before. Thank you!
I read the whole tread to the bitter end now.
I just ordered 2 LM4 for my brother for xmas and me which i hope to recieve in 2 weeks.
I cannot find the Opple Home App for IOS or Android in the stores anymore…
If you find the time to work on the windows version again, i would think a totally black background would be better (when using low lux lights).
I would like to donate a little bit via paypal.
PM or post your email here.
Good luck!
thank you for your recognition and advice. I don’t need donation, if I continue to optimize the windows software, it’d be purely out of my own interest.
Full screen mode via f-key like VLC and many other programs or the spacebar with (black background) and a dim font-color which would be the best to not interfere with the sampling.
Or just a black screen?
The LM3 sensor uses the AS7262, which has 6 channels in the visible wavelength range, while the LM4 sensor features the AS7341 with 8 channels. Although the LM4 supposedly has better hardware, the original LM3 development team left Opple without a smooth transition (see here). LM4 was then developed by a team lacking expertise in color science. Since its launch, we’ve noticed that LM4’s measurements have been inconsistent, suggesting the product may have hit the market before the app was fully refined. Steve mentioned that no one in the development team specialized in colorimetry, so he had to self-train to enhance the app.
Here are the specs of the sensors used in LM3 and LM4
The sensors in these devices are nowhere near the quality of those used in even a moderately acceptable spectrometer, which makes their accuracy inherently limited. To illustrate, the sensors in LM devices can be comparable to a SD 360p camera, while those in a proper spectrometer are comparable to a 4K camera. While a 360p camera is certainly better than having no camera at all, it lacks the resolution needed for detailed or precise results. I personally think we do not need such a high resolution or accuracty for our purpose (testing flashlights) and that is why I thought LM devices were useful.
I’m disappointed to see that Opple has decided to discontinue its LM product line. These devices provided a useful and cost-effective way to assess the quality of lights.
Thanks to the users here, we can at least make the most of what we already have.
Thanks for the fantastic synopsis. Especially helpful for me since I haven’t been following this thread closely. Maybe @ChibiM could put a link to this on first post of thread.
Does the mod for Smart Lighting improves/affects the readings, or just those features you listed? They are for Android only right? My Opple Smart is working fine on my iphone and I’m not good/knowledgeable with technical computer “stuffs.” I’d rather leave well enough alone. Thanks again for the great post.
Regarding the apk:
AFAIK the readings are not affected. The app usability is much improved, as is your phone security/privacy, as it can be used sandboxed without internet. The apk is only for Android.
From what I understand, the R9 readings vary across different versions, while DUV and CCT values remain relatively consistent. My focus has been primarily on the R9 measurements. (See here.)
Here are the R9 measurements for my TS10 6000K across various versions:
SMART version=3.7.1, R9=83 (this measurement was similar to earlier version of HOME before 3.3.1)
HOME version=3.3.1, R9=60
HOME version=3.5.1, R9=40
Currently, the Opple HOME version is 4.3.1, but the R9 measurements for my TS10 6000K LED remain unchanged at around 40. The same applies to the Opple Smart Lighting app. However, Steve’s latest desktop app reports an R9 value of around 85. Steve claims it became more reliable, but it does not fit my needs.
For my purpose of distinguishing R9 measurements across different lights, version 3.3.1 appears to be the most consistent when compared to more reliable measurement tools. Using 3.3.1, I can effectively differentiate between low-R9 but high-CRI LEDs, such as the LH351D, and high-CRI, high-R9 LEDs.
I installed Opple Smart from the play store, but could not get past the Welcome to Opple Home/Get Verification Code page.
In both iphone and Android, I entered my email but got the message “Data Analysis Error32001”. The other choice is phone for verification but it doesn’t work because the field already have +86, whereas mine is US +1. Any suggestion pls?
I have just checked my high CRI lights with the other app, Opple Smart. At least it is in the ball park with trend somewhat “as expected.”
I tested about 25 lights with LM4 for R9. Most lights have “highish” CRI LEDs, the lowest being LH351D in Sofirn SP36 BLF. I was pleasantly surprised to see that LM4 is not bad with R9, as long as you recognize it as an “amateur” device, more to follow trends and compare notes with pro tester’s numbers, less to publish exact numbers. I tested 4 groups of lights:
Highest group, R9 in 90’s: Nichia 219b and B35AM 4500k - passed, all mines in the 90’s.
Next highest group R9 in the 80’s: Nichia 519a 4500k (Simon quoted me Ra 93.6, R9 82, R12 80) - passed, all 4 lights in the 80’s, high 80’s.
Next lowest group GT-FC40 R9 in the 70’s - wide range 76-86, but nothing outrageous, so passed, as long as your recognize the caveat I mentioned above.
Lowest group in the low 70’s: LH351D 4000k - R9=70, so yes, seems to pass.
Anyone with more accurate numbers, where each LED’s R9 is “supposed” to be, pls correct me as needed. Number 4 is actually important to me because I am not sure I want to see R9 in the 90’s for this green LED. This indicates an ability to show R9 in “proper range,” whether it is high like 219b’s or low like most non-Nichia LED’s.
Here are measurements of high-CRI LEDs with varying levels of R9. I selected these specific LEDs because I have the exact models from the same manufacturer. It’s important to note that LEDs can vary significantly depending on the bin used, so measurements might differ even if the model numbers are identical. However, since my lights were purchased around the same time the reviews were conducted, there’s a good chance the LEDs came from the same bin.
Reference Measurements
Samsung LH351D 5000K (Sofirn SP10 Pro, reviewed by zeroair) Review link
CRI: 88
R9: 43
Duv: 0.0086 (output level: 4/5)
Nichia E21A 5000K (Noctigon KR4, reviewed by maukka) Review link
CRI: 97
R9: 96
Duv: 0.0004 (output level: 5/7)
LatticePower CSP2323 6000K (Wurkkos TS10, reviewed by koef3) Review link
CRI: 93
R9: 67
Duv: 0.0033 (output level: not specified)
My Measurements
Below are my measurements, taken with the LM4 using different software versions. All measurements were taken at output level 5 (stepped ramp, max level 7).
LH351D 5000K
CRI: 88.1, R9: 30.1, Duv: 0.0070 [Opple HOME 3.3.1]
CRI: 89.6, R9: 61.5, Duv: 0.0077 [Desktop 1.2.1]
CRI: 79.3, R9: -32.7, Duv: 0.0077 [Opple HOME 4.3.1]
CSP2323 6000K
CRI: 92.0, R9: 56.6, Duv: 0.0036 [Opple HOME 3.3.1]
CRI: 94.6, R9: 81.3, Duv: 0.0040 [Desktop 1.2.1]
CRI: 87.6, R9: 29.9, Duv: 0.0040 [Opple HOME 4.3.1]
E21A 5000K
CRI: 96.4, R9: 92.1, Duv: 0.0011 [Opple HOME 3.3.1]
CRI: 93.9, R9: 84.5, Duv: -0.0005 [Desktop 1.2.1]
CRI: 95.3, R9: 81.3, Duv: 0.0009 [Opple HOME 4.3.1]
Comparison of R9 Measurements
LH351D 5000K
30.1 [Mine, Opple HOME 3.3.1]
-32.7 [Mine, Opple HOME 4.3.1]
61.5 [Mine, Desktop 1.2.1]
43 [Zeroair, reference] comment: Opple HOME 3.3.1 is the closest to the reference. HOME 4.3.1 shows negative R9. This seems weird.
CSP2323 6000K
56.6 [Mine, Opple HOME 3.3.1]
81.3 [Mine, Desktop 1.2.1]
29.9 [Mine, Opple HOME 4.3.1]
67 [Koef3, reference] comment: Opple HOME 3.3.1 is the closest to the reference. Desktop 1.2.1 shows very high R9 that is indistinguishable from R9 from my Nichia E21A.
E21A 5000K
92.1 [Mine, Opple HOME 3.3.1]
84.5 [Mine, Desktop 1.2.1]
81.3 [Mine, Opple HOME 4.3.1]
96 [Maukka, reference] comment: Opple HOME 3.3.1 provides the closest match.
Conclusion
For all three LEDs, the measurements from Opple HOME 3.3.1 align most closely with the reference data, making it the most reliable software version for assessing R9 values. While I don’t expect the LM4 to deliver absolute accuracy, I aim to use it to distinguish lower-R9 LEDs among high-CRI options. For this purpose, I believe version 3.3.1 is the most suitable.
, I put light on tripod and mark where the hot spot is. Nearly all LEDs change Duv with less brightness from step-downs, so I have active cooling to keep brightness stable.