TASI632A also equipped with USB output for easier runtime measurement via PC/laptop with OEM software.
Check Djozz thread about it here: Tasi 632A luxmeter, some tests
- Clemence
Could an ultraviolet light camera lens filter be used to flatten the response of the Tondaj LX-1010B?
Then use a multiplier to correct the results.
Of course if you cleverly combine colour filters you will influence the wavelength response. My first thought is also: how hard can it be, but I donāt know why, but making the colour filter really right it appears difficult and expensive, that tiny filter is the most expensive bit of a good luxmeter.
Thank you , i appreciate your help . I will think about it 
Thanks for the testing mate!
I have a generic light meter with a LX-1330B and i also have the UNI-T UT383BT. The Bluetooth edition and they read within a few lux of each other the UNI-T seems to read lower on most lights.
Thanks for another very informative test. If the covers between any of the units (especially the Tasi and Uni-T) could be swapped, it could be very informative to remeasure both to see if and how the results change.
Someone just did another āpost - deleteā action?? I hate when people do this.
I got the notification, saw his early post. Then another notification brought me to the āpage not foundā. Checked and he already deleted all his last two replies.
- Clemence
Yep, happened to me too.
Where would I purchase the MobiLux Class A meter from?
Djozz, I moved my calibration box next to my PSU. And now this TASI-632A can not measure anything near it! I know the sensorās cable is sensitive to metal objects but looks like RD DPS5015 emits rather powerful EMI. I have to move it farther away to ~ 1 meter. I canāt even move the 18AWG lead cable (from that PSU) any closer than 40cm from the sensor. I fluctuates heavily depending on the cable movements.
Any good EMI cable insulator for this kind of problem?
- Clemence
Thats not good to hear clemence. My plan is to use a DPS5020 with a Tasi 8133. Almost every part is waiting at home. But if the 8133 also is sensitive regarding EMI i will have to rethink my buildplan.
Usually this kind of cable is using a metal wire mesh shield. If this cable is without the mesh it will be hard to isolate the cable from EMI radiation because the sensor cable is twisted.
Something like that (https://www.google.com/search?safe=off&biw=1568&bih=809&tbm=isch&sa=1&ei=ftxqXMmIM4LJwAKjvJDoAg&q=emi+wire+mesh&oq=emi+wire+mesh&gs_l=img.3ā¦95840.98690ā¦101288ā¦0.0ā¦0.75.595.10ā¦ā¦1ā¦.1ā¦gws-wiz-imgā¦ā¦.0j0i30j0i19j0i10i19j0i8i30i19j0i30i19j0i8i30.ps6yNnRgwZ8#imgrc=vSAhbou2P58pZM:) should work but like i said the twisted sensor cable is making it hard to wrap the cable into a mesh tube.
Hmmm, Iāll try to get stuff like that from local sources. Thanks for the info TOD
- Clemence
At least it is not my expertise at all Iām afraid. Btw, my Tasi-632A is on its way to Enderman now so I canāt do any tests on it anymore.
The cheaper Tasiās seem not to have such problems, at least I did not notice it, but they measure less sensitive so you may just miss it.
Having problems with interference in cables? Foiled and shielded twisted pair network cables may come in handy in this regard. Even standard UTP can offset certain interference by design on each colored pair. 
Thanks Bark =)
Wrapping with aluminum foil seems to work so far
Hey djozz, have you observed your lux meters calibration drifting over time, or identified any pattern of how they shift? Iām measuring some lights in my sphere with a tondaj lx1010b and noticed 3 regulated lights now reading 10% lower than they did a month ago. Not sure if itās the meter (battery, ambient temperature differences) or some change in the sphere. Thanks.
Could be the Covid-19, itās affected everything else, so why not?
Seriously, change the battery and compare the results.
Eliminate the variables.
Later,
Keith
I have calibrated mine and used off and on for months and go to check calibration again and its still spot on.
It could be meter specific though, I would try the battery first like Muto suggested.
Temperature could also change the reading a little, I know a few degrees cooler battery can decrease current capabilties.
Li-ions perform better when warmer.
would be interesting to know for sure, if they can drift off so quickly.
I have not seen luxmeters noticably shift myself,
I have my Mobilux meter that was 3.4% off two years ago when I compared it next to one that was calibrated that same year. It had not been calibrated for 8 years at that point. Officially they need re-calibrating every year but it feels not needed.
Before that I used a Tondaj meter for years, and my reference flashlight measured the same within 1% for years.
Maybe you see some yellowing of the inner surface of your sphere over time? But that is expected from the influence of light, and generally the inside of a sphere is dark.