cheap chinese video light review

[QRikard]

I received two lights from AliExpress. The order model was AS27-1H but the instruction manual says Sealion-B15. It was sold as a 20000lm light. 12000lm disappeared as soon as I opened the instruction manual. The manual states 8000lm. The brand is LetonPower. Other brand option was BRETT but I went with LetonPower because photos of it showed a brass ring on the PCB for positive battery contact. I don't like plain ENIG plated PCB for contact.
View attachment 862045
The first thing I did was adding a plastic stick to the head to prevent the PCB from rotating. I just glued it into place with hot glue and cut to proper length.
View attachment 862046
I have access to a dark room lab at work.
There I measured the spectrum of the light and colour temperature. From the spectrum I could calculate the CRI. The leds are cheap chinese leds with colour temperature of 7200K and CRI of 67.
View attachment 862048
I also measured the leakage current in off state. It was only 17uA which is very good.

I ordered a third light which I will use for measuring the led driver circuit and for prototyping a magnet+hall switch upgrade for the buttons.

I will also measure the lux and lumen output of the lights. I have access to an integrating sphere lumen meter but I don't know the correction factor to the reading (lux meter reading to lumens). I'll probably measure the lux reading across the light pattern and calculate lumens of it.

Really nice to see measurements even if i'm not to happy about the results of a CRI of 67%. Was really hoping for more...

The PCB in mine was glued and very firmly attached.
Also added REED relays with success. de-soldered the push button and added the reed relay instead and then attached the pcb with a small dab of molten glue to make it stay in place when i filled the hole with transparent epoxy (the led indicators still work nicely).
This way i never needed to open the light and fiddle with the other electronics glued in place.

I would recommend to use weak magnets and close to the reed relay to avoid interference to the compass. I used 5mm diameter and 3mm thickness neodymium magnets and those impact my compass at a distance of approx 20-30 cm. I have ordered smaller magnets to try

 

[Scuba-Lad]

Really nice to see measurements even if i'm not to happy about the results of a CRI of 67%. Was really hoping for more...

The PCB in mine was glued and very firmly attached.
Also added REED relays with success. de-soldered the push button and added the reed relay instead and then attached the pcb with a small dab of molten glue to make it stay in place when i filled the hole with transparent epoxy (the led indicators still work nicely).
This way i never needed to open the light and fiddle with the other electronics glued in place.

I would recommend to use weak magnets and close to the reed relay to avoid interference to the compass. I used 5mm diameter and 3mm thickness neodymium magnets and those impact my compass at a distance of approx 20-30 cm. I have ordered smaller magnets to try

Interesting. Do you have any photos of this setup? I used Piezo switches in mine, and ended up drilling additional holes for the power LED indicators with 3d printed transparent plastic covers (3mm thickness) posted earlier in this thread.

 

[34109411]

i bought twp APLOS light from Alicrap i paid like 40$ cad each if i recall. So far So good, i doubt they are 3000 lumens as they say but they do the job for now.

 

[QRikard]

Interesting. Do you have any photos of this setup? I used Piezo switches in mine, and ended up drilling additional holes for the power LED indicators with 3d printed transparent plastic covers (3mm thickness) posted earlier in this thread.

Found some photos on my phone. Purchased 14 mm reed relays with plastic encapsulation to minimize the risk of breaking it when bending the leads because you need to bend them quite aggressively to fit and to solder on the pads from the original switch (removed).

This is not the latest version of the magnet, i realized that it's better to mount the switch on the side to minimize the risk of turning it on by accident when setting it down. I use 1mm bungee cord to retract the magnet.

 

[QRikard]

I have access to a dark room lab at work.
There I measured the spectrum of the light and colour temperature. From the spectrum I could calculate the CRI. The leds are cheap chinese leds with colour temperature of 7200K and CRI of 67.
View attachment 862048

Have you tested the COB lights or similar model from aliexpress?
Is there a chance of better CRI from this version?

Multi-funktionale IPX8 Fotografie 3 Farbe Tauchen Taschenlampe 80m Scuba Unterwasser LED Licht COB Taschenlampe - AliExpress 39

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

I like this format of the lights and function after switch mod, but better performance would be nice. Really nice of you to share the measurements!

 

[1c3d1v3r]

Have you tested the COB lights or similar model from aliexpress?
Is there a chance of better CRI from this version?

Multi-funktionale IPX8 Fotografie 3 Farbe Tauchen Taschenlampe 80m Scuba Unterwasser LED Licht COB Taschenlampe - AliExpress 39

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

I like this format of the lights and function after switch mod, but better performance would be nice. Really nice of you to share the measurements!

I have only tested the model mentioned in my post. I will also test a BigBlue 900€ light many of my dive buddies use.

I checked some Cree datasheets and prices. You can't even buy the genuine leds for the price of the whole video light.

My idea is to have two light on the setup and also 2-3 extras which can be shared with dive buddies and also use as drop light. I can place the drop light into wrecs and caved before filming.

I can also test other light if you send me one as gift or pay return shipping.