4 new luxmeters compared (sept 2018)

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djozz
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4 new luxmeters compared (sept 2018)

 

I thought that after my test of 5 luxmeters in april 2018 I was done with luxmeter testing (not exactly a cheap pastime if you want to test anything else but very low-end meters), but then early this summer Enderman came with an unusual proposal: he would buy the Tasi 632A luxmeter that I tested in april this year off me for the new-price, so then for the money I could buy a couple of other new luxmeters that he found interesting, to be tested by me. In the end both he and I spent even more money than that and I ended up with 4 new luxmeters to test, among which a rather pricy Extech meter. Thanks Enderman for supporting the advancement of BLF-knowledge!

 

Links to earlier luxmeter posts:

http://budgetlightforum.com/node/30787 (april 2014, construction of a Ceto luxmeter sensor yell , see post #2 of today's thread for more chinese luxmeter-sensor construction fun!)

http://budgetlightforum.com/node/33929  (sept.2014, general information about luxmeters, test of Mobilux ClassA, Tondaj LX-1010B, Ceto CT1330B)

http://budgetlightforum.com/node/39477 (may 2015, an attempt to use the ambient light sensor on my phone as a luxmeter)

http://budgetlightforum.com/node/60218 (april 2018, test of Mobilux ClassA, Tondaj LX-1010B, Uni-T UT-383, Tasi 632A, noname LX-1330B)

 

The four new luxmeters:

Extech LT45, bought on Amazon for total 370 dollar shipped plus import fees (it is much cheaper in the US, buying US stuff in Europe is very expensive)

Tasi TA8132, bought on Aliexpress for 18 dollar

Uni-T UT382, bought on Aliexpress for 44 dollar

SmartSensor AS803, bought on dx for 16 dollar

 

*The Extech LT45 meter I had high expectations of because Extech meters are used by many flashoholics who seem to take their hobby serious. I bought one without NIST-calibration certificate, because I was more interested in the complete spectrum response than a piece of paper proving a calibration against a 2700K tungsten lamp (I'm sure that the factory calibration of a manufacturer like Extech will be done well enough). A useful feature of the LT45 version is that it has the option to enter your own calibration, which comes in handy in integrating sphere use, to incorporate the sphere multiplier directly into the luxmeter read-out.

*The Tasi TA8132 meter is one of the newer models by Tasi, since the expensive Tasi 625A tested quite well in april it is interesting to know how their very cheap models behave.

*The Uni-T UT382 meter is the other way around, the ultra-cheap UT383 that I tested in april did not do bad at all considering the price, how does this 44 dollar model with USB data transfer do?

*The SmartSensor meter seemed the cheapest of the cheapest to me, does its performance surpise?

 

First a (for flashaholics innocent) real world comparison: of a number of flashlights with different tints and CRI the throw (brightness of the hotspot) at 7 meter was measured with the different luxmeters, including my Mobilux luxmeter as a reference, and as a second reference the reading of the Gossen Mavolux Base (this spectrometer is also a class B luxmeter). Notice that to get stabile output (=less than 0.5% output drop over the course of these measurements) most flashlights were not at the highest mode , so the numbers have no absolute value, just relative between the luxmeters. The calibration of my Mobilux meter was corrected to a well-calibrated unit earlier this year (mine read 3,4% low), this correction is incorporated in these measurements. As a new feature I recorded the spectra of the measured hotspots Smile :

 

 

 
 

Luxeon V 4000K 70CRI

(Thorfire VG10)

XM-L2 6500K 70CRI

(Sunwayman D40A)

XM-L2 3000K 90CRI

(Kaidomain K2)

dedomed XP-G2 S4 3D

( "Mitko Thrower" )

N. E21A 6500K R9080

(Olight M10 Maverick)

219B V1 4500K R9080

(Jaxman M2)

Epileds 400nm UV-led

(Ultrafire C10)

MobiLux Class A 61,7 289 42,3 1108 131,1 122,5 2,17
Extech LT45 64,9   +5% 309,1   +7.0% 43,0   +1,7% 1167   +5,3% 137,4   +4,8% 126,6   +3,3% 26,12  
Tasi TA8132 59   -4,4% 300   +3,8% 41   -3,1% 1052   -5,1% 150   +14,4% 131   +6,9% 9
Uni-T UT382 62,8   +1,8% 364   +26,0% 40,7   -3,8% 1144   +3,2% 180,1   +37,4% 144,2   +17,7% 22
SmartSensor AS803 39   -36,8% 266   -8,0% 24   -43,3% 902   -18,6% 127   -3,1% 104   -15,1% 119
Gossen Mavolux Base 56,8   -7,9% 281   -2,8% 37,9   -10,4% 1075   -3,0% 126   -3,9% 114,6   -6,4% 15

 

The results are clear:

*despite the substantial purchase price the Extech LT45 luxmeter is good value for your money, you can express the difference with the Mobilux meter over the numbers obtained for these measured light sources as a 4.5% calibration difference and 1,35% variation in spectral sensitivity. This is closer than how the classB luxmeter read-out of the spectrometer compares to the Mobilux classA (with 5.7% calibration difference and 2,5% spectral variation).

*the surprising performer is the Tasi meter, for 18 dollar I got a luxmeter with on average 2.1% calibration difference and 6.3% spectral variation, compared to the Mobilux meter. I calculated the corresponding numbers for the LX1330B in my april test: 3.2% calibration difference, 8.3% spectral variation. So I take this Tasi meter any day over the LX1330B. But beware!, you may be in for a disappointment, in post #2 of this thread I describe another Tasi meter from the same series that looks the same but is built much much cheaper and although I have not measured it, it probably has much worse performance, you will not know what you buy!

*the surprising looser is the 44 dollar Uni-T UT382 luxmeter, measurements are all over the place, this is a very bad luxmeter.

*the SmartSensor is cheap and bad.

 

To get a grasp on why the luxmeters do not just show a calibration difference but also read so different for different light sources, just as in the april 2018 test for these new luxmeters I recorded the spectral response to a 2700K tungsten light source. This should give an idea of the differences in spectral response of the various luxmeters and may explain why they read so different for light sources with different spectra. For a description of the method, using an antique but strong-going Zeiss prism-monochromator, see the link above to the sept.2014 test.

First I show some validation data of the method, just because I want to show that my home-made contraptions actually do work.

Every time I do a series of tungsten lamp spectral response tests on luxmeters, I have to build up the measuring rig completely (me and my family live small, my allowed hobby space is 2.5 square meters of the appartment) align the light source with the monochromator again, and power the tungsten lamp with the exact same current (6A). This alignment is a bit different every time, and so is the read-out of my Mobilux meter that I use as reference. To get an idea of the robustness of the method, here's a comparison of the tungsten lamp responses of the Mobilux meter of the april2018 session and the sept2018 session, with the highest read-out values normalised to 100:

 

 

That looks consistent enough to me, what I see mostly is a shift of about 2nm, differences with tungsten lamp responses of other luxmeters are way higher than this Smile

 

A valid question is why do I use the Mobilux luxmeter as my reference, as if it shows the absolute truth. It is an instrument after all and will have its errors and tolerances. First and mostly: because it is the best portable luxmeter out there, and it is recently calibrated against another Mobilux luxmeter that is being officially calibrated each year. I have no option to do any better so it will just have to do. But to give an idea how good the spectral response is, I confidentially received a test rapport of this type of meter showing the errors of the spectral response compared to the reference V-lambda curve, and without showing the actual (confidential) data, here is the tungsten lamp response of the Mobilux meter in the visible light range compared to the tungsten lamp response if the Mobilux had a perfect V-lambda response:

This is assuming that the Czibula&Grundmann test data are trustworthy, which I have no doubts of. You can see that they managed to make a detector/optical filter combination that comes extremely close to the V-lambda response.

 

So far the validation, here are the tungsten lamp responses of the 4 newly tested luxmeters, together with the Mobilux luxmeter:

 

I find it extremely difficult to pinpoint, by analysing these curves, why the luxmeters read the light sources in the table above exactly like they do. But the general picture that arises from these curves is more clear:

*the Uni-T UT382 luxmeter and the Smartsensor AS803 luxmeter both deviate immensely from the reference luxmeter for some light sources in the table, and for different reasons as you can see in the graph: the SmartSensor's spectral sensitivity shows a large shift, on average 20nm, to the right compared to the Mobilux, and the Uni-T's spectral sensitivity is just completely weird and nothing like a V-lambda response.

*the extech LT45 luxmeter has a tungsten lamp response that matches the Mobilux response pretty well, shift and tilt the curve just a bit and you are there, and the Tasi TA8132 meter does not bad either, it overreads blue and red somewhat.

 

One more graph, a couple of interesting curves from the april and september sessions combined in one graph:

The LX1330B has the worst curve, followed by the very cheap Uni-T UT383 (that in itself does way better than the weird newly tested Uni-T UT382 which I left out in this graph), the two Tasi-meters seem to perform similar, their curves deviate differently from the Mobilux curve but the amount of difference seems comparable.

 

 

Conclusion:

*I trust the Extech LT45 meter to be pretty good, the tungsten lamp response curve makes me think that also other white light sources would be measured pretty accurately.

*The Uni-T UT382 completely fails to perform, do not buy. I may open it up at some point to see if it has a shifted optical filter so that light can enter the sensor bypassing the filter. in that case the quality control has failed.

*The SmartSensor AS803 is cheap and performs bad, even worse than the LX1330B. Even for the price it is a bad buy.

*The tested Tasi TA8132 meter performs surprisingly good for what you pay. It would be very good value for money if only Tasi was not in the process of cheaping out their TA813x luxmeter series and you may be buying a low-grade self-clone from Tasi. (see post #2 for the explanation)

 

Edit: more luxmeter dissection and tests in post 2, 18, 22, 30, 49, and look through this thread for Docc's and other's  thorough crusade into where to find the "good type" cheap Tasi meter cry

 

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

Edited by: djozz on 10/15/2018 - 10:13
djozz
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So I was very happy how the Tasi TA8132 of the test above performed, so I ordered the 'upgrade' TA8133 on Aliexpress: only 2 dollar more and in the lowest range it has a digit more in the read-out, it shows a tenth of a lux instead of just lux. I did not expect a more accurate sensor but I hoped for a stable enough read-out at the lowest range that the extra digit was meaningful.

 

It turned out different. I received a completely different luxmeter. It looks the same apart from the extra digit, but if you look closely, everything is different. And I do not know if this is specifically the TA8133 that is completely different from the TA8132, or that the whole TA813x series was overhauled at some point and that you may receive a 'new' TA8132 too if you are unlucky. Let's have a look at the outside:

 

 

"Good old" Tasi TA8132 on the left, "downgraded" Tasi TA8133 on the right

You may notice:

*slightly different colour of red

*red top on the left, black top on the right

*different colour LCD display

*more sloppy telephone wire on the right

*larger, slightly matted, and more opaque sensor diffusor on the left

*plastic texture of the sensor is bit different (can not be seen on pic)

 

This is all unimportant to me but it shows that they completely re-invented this luxmeter, nothing went untouched.

Now the inside of the sensors:

 

Sorry, reversed now, old TA8132 on the right now, new TA8133 on the left.

*the old type had a loose diffusor precision-aligned with some plastic posts, the new type diffusor is molten down (=not neccessarily worse, but cheaper to make)

*I received the new type TA8133 with something rattling inside the sensor, it appeared to be the optical filter that lived loose in the cavity yell. It was made press-fit into holes in the circuit board but to the wrongs specs: it had no grip at all when I pressed it back in place, I had to use cellotape to make it stay. After that the reading was completely off, I guess they calibrated it already without filter. The old type TA8132 has a screwed-down optical filter that will not go anywhere.

*the optical filter of the new type is not completely clear, and the sensor is heavily scratched (because of the loose filter going about?). the old type has a clear filter and fairly clean sensor

*the optical filter window of the new type is small and the sensor is well off-center, I fear for the cosinus-response of this luxmeter. The old type has a large window that will not influence the optical path to the diffusor.

*the sensors themselves are not the same type, they are of a different make (I did not remove the optical filter of the tested  TA8132 because I fear for altering the calibration, this luxmeter will still be used).

 

 

So with different optical lay-out, different diffusor, different optical filter and different sensors, in fact these are completely different luxmeters. I would have to test this TA8133 all over again to see if it is any good. And with everything looking less well done, I fear for less performance as well. But who knows...

 

Because I'm not sane and despite knowing better, I ordered one more TA8132 and one more TA8133 luxmeter, from different sources to see if these differences are consistent. They probably will dropship from the same source after all but who knows.

 

China is a weird country..

 

Edit oct.5, next chapter in post #18

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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Thank you so much for  all the knowledge you share here !

 

The fun fact is that this thread pops up exactly while i was searching AE, BG etc for a cheap luxmeter after reading your previous tests and decided to have a go with the cheap integrating sphere Wink

I have access to a Konica-Minolta T-10A at my workplace and borrowed it once to do some quick comparison between whatever flashlight i had at hand but i would like to have something at home. I am not the "official" user for the T-10A and prefer not to over-work (not sure if this one is correct english) the permission i have for using it.

 

Edit : Holding my breath for your next update as i was about to hit the buy button for a TA8133 when i saw this thread

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You’re welcome.

The TA8133 is exactly the luxmeter that I bought a few months later than the TA8132 from the test, and it came with a nasty surprise that I will show in the second post: apparently Tasi cheaped out and completely overhauled the TA813x series with by the looks of it inferior parts. If it is the TA8133 that is made cheaper than the TA8132, or that they swapped the whole series by cheaper versions, I don’t know.

Tasi has made some good products and now they are killing that little bit of reputation that they had (with me at least).

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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Thnx for the test Djozz. Surprised to see the uni-t perform so bad. The cheaper 383 is performing better.

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Excellent test Big Smile Thank you!
Glad you could finally test that Extech meter you wanted Silly

That TA8132 looks excellent, maybe even better than the 632A?
What do you think?

Looking forward to see post #2.

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post #2 finished, do you still want to gamble on Tasi meters?

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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djozz wrote:
post #2 finished, do you still want to gamble on Tasi meters?

Interesting, will have to see how it performs I guess.
They no longer have the 32 on their website, now only 31 and 33 and 34 :/
From the specs it should be like one percent more accurate, maybe they decided to cut down manufacturing cost elsewhere or maybe it is a fake?
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Looking at everything, including the packaging, I think these are both from the same manufacturer, so not fake but they cloned it themselves. and indeed there is a possibility that the performance has not suffered (I doubt that though) but I could not test that because of the loose filter. If the new one (just ordered it, will receive in a few weeks) has no defects this time, I can do a quick performance test measuring some flashlights comparing it to the “old type”.

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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Yeah, a comparison to the 32 should be enough to see if it is close or not.
Hopefully it isn’t a decrease in performance :/

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Looks like someone in yet another emerging enterprise thought: hey, let’s bring in a CFO.
And he/she introduced extra manufacturing stages: involving beancounting and cutting corners.
So after a while they succeeded in saving 20% of the cost (and 80% of their quality and reputation).

A bit like the farmer who complained: I spent a lot of time learning my cows how to live on air only.
Now the ungrateful animals all have died on me, leaving me in a fine mess.

I always think long and hard before I say something really stupid.

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Thanks Thumbs Up

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It looks like the TA8132 may have been discontinued.

I took a chance and bought a boxed one, hoping all the existing stock is good.

http://www.china-tasi.com/en/Product/Digital_Light_Meter/

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Yeah, replaced the 8132 with the 33 and the 30 with the 31.
Now there’s also an 8134 which I didn’t remember there being last year.

We will have to see how the crappier quality 33 compares to the 32.
Assuming that they use the same type of filter and calibration it should be almost identical, but only a test from djozz will be able to tell Silly

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Reading djozz’s second post leaves me with little hope of the 8133 being a decent meter. Maybe a first batch had some bad components and the build house didn’t know or care enough to stop in time, its possible the next batch is better. That still makes buying it a lottery though.

There’s lots of 8132’s still around on Aliexpress, its probably the safer bet. The one I ordered is due in forty Ali days, probably won’t see it till the end of November.

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I don’t know where you are located but usually aliexpress is much faster than that, on average two weeks to my home.

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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djozz wrote:
I don’t know where you are located but usually aliexpress is much faster than that, on average two weeks to my home.

Wow. That’s fast. My average is more like a month. Maybe even more.
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I got my second TA-8133 luxmeter in today (the type with the extra digit). From a different seller, frank hu’s store this time ( https://www.aliexpress.com/item/Handheld-Split-200-2000-20000-200000-LUX... )

My and most reader’s theory was that when developing the TA-8133 after they made the TA-8132 first, they did the downgrading too so all TA-8133 must be bad.
But no, that would make way too much sense, this is China so logic is completely absent: this copy is of the same build as the good quality TA-8132 that took part in the test of the OP. So it has the red top, neatly coiled telephone wire, matted and bigger sensor-diffuser, etc. So the downgrading is not type-related, you may even order a TA-8132 and get a bad one Sad

And it works well too, the calibration seems pretty close (looks even like within 0.5% for the warm high CRI light in the video (the Mobilux reads 3.4% low)) and reads right down to zero in a nice and stable way.
I did not tell it before but in contrast to this, the cheaped-out version has a faulty calibration (probably because the optical filter was already loose while calibrating), but worse: it stops reading below 24 lux, everything below that is zero. Pretty useful that extra digit Facepalm

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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Wow that 8133 sucks, but I like how close the 8132 is to being correct Smile

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They are both 8133!! The left one is the latest one that I got in the mail today, the right one is the one dissected in the second post.

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

djozz
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Btw, I watched a few youtube video’s about luxmeters (among which a nice one from Big Clive), some show a teardown of the sensor unit and that “good type” sensor as shown in post#2 has been around for a while and can be found in almost all types of cheap Tasi meters, and also other brands.

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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It is luxmeter investigation night!

I opened the Uni-T UT382, the one with the terrible spectral response, to see if some optical filter was shifted or what, but it was all different inside: (first let’s ignore the dirt on and around the sensor Tired ) Uni-T went a different direction and decided not to use a separate silicon sensor plus optical filter, but use an all-in-one ambient light sensor, similar to what you find in your phone. No separate optical filter needed.

And that explains the very low performance, ambient light sensors usually have terrible spectral responses (which is why a luxmeter app does not stand a chance changing your phone into a half decent luxmeter).

I tried for half an hour to find this specific light sensor, and I may have found it: it could be a Renesas ISL29020 light sensor. I could not find a photo of this specific one but I found a picture of another Renesas light sensor that looks almost the same:

In the datasheet of the ISL29020 the bond wire layout looks correct, and it has a slightly recognisable spectral response Facepalm

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

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djozz wrote:
They are both 8133!! The left one is the latest one that I got in the mail today, the right one is the one dissected in the second post.

Oooh I see! My bad I got confused, thought you were comparing the new 8133 to the 8132 we knew was good.
So maybe that crappy 8133 you got was just a really old production version or something, some retailers have stock that is many years old.

I would like to assume that they improved the production quality rather than made it worse.
So that means there’s a chance of getting an old crappy unit of both 8133 or 8132 depending on where you buy from.

At least it’s easy to tell which meter is good or bad simply from the appearance Smile

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Thanks Djozz,

So Uni-T UT382 is bad despite price?

Djozz his cheaper brother UNI-T UT383 works fantastic for me… But only when I turn out to FC readout where I get easier readout (3 or 4 digits depending on light), and not only easier readout it seems that it is more accurate with FC readout also…

So I don’t know weather is possible that lux meter craps out when processing LUX(more digits) versus FC (less digits). I don’t know how and explain why but my Unit-T UT383 is simply better when I am doing measurements of performing lights(250 kcd + lights) with FC readout.

Modding is making something how you want it to be, not how it comes stock...

Old-Lumens

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Will you also test the TA8134?
Maybe you could make a picture from both TA8133 side by side with open sensor So its easy to see that they are not the same internaly. Would be interesting to contact Tasi and get a answere if the crappy one is the new or old version. If they answere at all! But the picture would help to bridge the language barrier.
Not interested in buying one if i have a 50% chance to get a scrappy Meter. But i am willing to ask my way through their support Crazy

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djozz
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I’m not really on an active mission improving the manufacturers. If my information gets so widespread (not likely, even here these luxmeter posts do not get many reads Party ) that customers and manufacturers take notice and make better stuff, I will be very happy, but I’m not going to contact them about them.

Atm, I’m not planning more luxmeter tests, that said I do not expect extreme different performance of the TA8134, mostly a different housing I guess.

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

SKV89
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Thanks for this valuable info! The Extech looks good!

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I have a TA8133 from an other seller waiting for the end of the hollydays in some chinese warehouse Wink

Will tell you what i find when it'll be here. (fingers crossed)

 

TheOnlyDocc
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I only wanted to ask them what i get when i order from them. Is the crappy one the old version and they upgraded to the better design. Or have they rebuild the good ones and now are selling a version nowbody wants.
I am not trying to change/help/work with them. I only would like to know if its woth to spend my money. So i would ask. But language is a problem contacting Chinese companys. A picture often says more than 1000 words. Here you are showing the TA8132/33. Is it the same with the crappy TA8133 and the good one? If yes this picture would be good enough!

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djozz
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I just checked the sensor of my latest (“good”) 8133 and it looks almost like the “good” 8132, but the rim of the sensor is different, so yet a different version, although in details. Would this different sensor be related to the better resolution at low light? Nah, that would sound like reason, they probably use whatever component is available at the time of production, sometimes this one, sometimes another. Big Smile

link to djozz tests 

“I used to think that top environmental problems were biodiversity loss, ecosystem collapse and climate change. I thought that thirty years of good science could address these problems. I was wrong. The top environmental problems are selfishness, greed and apathy, and to deal with these we need a cultural and spiritual transformation. And we scientists don’t know how to do that.”   (Gus Speth)

TheOnlyDocc
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Thanks djozz! Mail is out and i will post the result when/if i get a answere!

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