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

I don’t think there’s a “Pro” model (yet). Those Pro-images are around since I bought the Opple months ago. Asked Opple and got no answer. Also, the naming is inconsistent. Sometimes it’s called Lightmaster III, sometimes it’s Lightmaster G3. The App is called Lightmaster Pro.

I bet someone was working on an improved model, maybe using a CCD with more suitable color filters, and hence the renderings and the made-up app pictures with R9. But I bet it would have been way more expensive with customized CCD, more in the range of other devices of this kind.

Another point: Let’s not seriously discuss the precision of the CIE diagram location. Mine was, iirc, 40 EUR. It’s fun, it’s useful in cases I stated above. But of course it is no scientific tool.

How can this device measure CRI without reading the spectrum?

Where it can be found for 40eur?

A monochrome sensor and a set of filters of the reference colors R1 to R8.

Filters transmitt spectrum. But the same color can has different spectrum. It is called metamerism.

But anyway thanks, this assumption led me to the right idea;)

There’s a link in this thread. Some german webshops also carry it. See if you find one that delivers to Russia with moderate s&h.

I downloaded a few of the older APK files, and none of them has the dark theme, with R9 measurement.

It's probably just a software thing, but not available to us, users.

Jon, I really agree with you. Not having accurate’ish DUV or R9 is the issue. CT are easy to make an informed guess about, still, but to a lesser extent after having looked at so many it is fairly easy to decide where the DUV is more or less. Camera shots with right WB and again a good eye will tell you a bunch on a calibrated screen.

Because Im also interested in comparing the flicker score of various LED light bulbs I have bought, I decided to contact Opple and have ordered one for delivery to USA

you all can wait for my review, or go ahead and open your wallet

here is the purchase link I used
opple from china to USA

I have no affiliation of any kind… I paid the price shown in that link (about $35 w shipping), for the one I just ordered. Will post impressions after it arrives.

Holy cow. $31 after coupon and shipping? That’s a pretty good deal for what it advertises to be. It may not be a professional-level tool, but according to the test results that have been posted here so far, it seems to do what it claims to do.

That’s what I consider a deep discount for a unique tool.

Congrats for finding it at this price! I’m sure you’ll like testing it. I’d be interested about your findings regarding lux measurements. I found some deviations from the Benetech GM1020, but that’s surely not a reference device.

This Opple is sold to professionals, and part of the job is measuring brighness. So, it should be good at that, taking into account there are standards about e.g. office/workspace brighness values.

I did a side by side test, at 5 meters, compared the lux measurement manually with my Hagner E4-X luxmeter.

Mode1-Mode4 were with a Olight Seeker 3 PRO with unknown LEDs

Thrower is a Fenix C7 with SST70 (not so much of a thrower, but more throwy than the Olight)

I used the Hagner measurement as 100%, and then did the math. I wonder what everybody else gets.

Here are the results in terms of candelas (calculated from the lux I measured)

Mode 1 275 cd
Mode 2 1375 cd
Mode 3 5000 cd
Mode 4 17000 cd
Thrower 59000 cd

So, an average of about 11% higher than the Hagner.
The 9% at the start and 14% at the second mode are not as consistent as the other measurements that were close to 11% each time.
So that is good to know. Just take off about 10% of the measurements, and it should be okay!

> I did a side by side test, at 5 meters

thanks for sharing your testing… what light source and LED did you use?

There may be variations due to spectrum. In any case 11% is not enough to worry me.

Within 10% is acceptable for a ballpark figure and good enough for casual testing. For around $30, that’s very good.

Thank you, Chibim!

I have inconsistent results with the Benetech, depending on LED. But the culprit is probably not the Opple but the GM1020.

I didn't mean to say that 11% was bad, but more like: if you subract 10% of the readings it should be in the ballpark.

The first few measurements weere done with the Olight Seeker 3 PRO (unknown LED)

and the 'thrower' is actually a Fenix C7 with SST70, which isn't very much of a thrower, but more than the Olight :)

10% high sounds good enough, and after 10% substraction you are within a few percent. For a complete picture how it performs as a luxmeter, light sources with some more varied spectra could be compared with the Opple+Hagner , from 2700K to 6500K, from 70CRI to 95CRI.

fwiw, there can be a large difference in the way my light meter reads LEDs

for example, the SSC P4 in my Original Novatac, reads 70 lumens on my meter… but Hogo swears he calibrated it to 120 lumens, after making an adjustment for the spectrum of the LED

by contrast my HDS w XP-G, which is factory calibrated to 200 lumens, reads 210 lumens on my meter… which I then adjusted to match the 200 lumen HDS.

so, an XP-G reads very different than an SSC P4

another example
Maukka bought a 200 Lumen HDS w sw45k. On Maukkas meter it read 235 Lumens. This tells me that HDS used a different spectrum conversion factor than Maukka.

so yes, if the Opple reads within 10%, that is totally OK, and can be attributed to testing Low CRI Cool White LEDs, which read differently than High CRI LEDs, or LEDs with a different spectrum distribution.

Im looking forward to comparing the Opple to my Light meter… with various different LEDs…

I am looking forward to comparing it with my Canon 5D ii spot meter, it seems to be very good a color temps.

Next little test.

Distance is approximately 4 meters this time.

Solarforce with warm white Nichia High CRI (can't remember if 119 or 219)

Hagner Opple
2275 cd 2475 cd
100 % 108.79 %
= 8.8% higher