SKV89's LED Strips and bulbs test results

46 posts / 0 new
Last post
snakebite
snakebite's picture
Offline
Last seen: 18 hours 2 min ago
Joined: 11/20/2013 - 20:21
Posts: 1974
Location: dayton oh

not good with variations in led vf and drop due to length.
the ones closest to the feed will be overdriven.
the resistors relieve this.

Jerommel wrote:
Meh, bypass the resistors with solder blobs and use a real driver for the lengths you cut yourself.
sac02
sac02's picture
Offline
Last seen: 2 weeks 4 days ago
Joined: 09/26/2016 - 15:18
Posts: 822
Location: TX

SKV89,

 

I took the liberty of putting your data in a spreadsheet (google sheet).

 

High CRI LED light strips (and a few bulbs)

 

Maybe you can add the link to your OP?

 

If you want to be an owner of the spreadsheet to make edits, PM me.

Joshk
Joshk's picture
Offline
Last seen: 1 hour 2 min ago
Joined: 09/09/2015 - 12:12
Posts: 2472
Location: USA

There is also a spreadsheet of SKV89’s stuff in the OP here: http://budgetlightforum.com/node/69967

sac02
sac02's picture
Offline
Last seen: 2 weeks 4 days ago
Joined: 09/26/2016 - 15:18
Posts: 822
Location: TX

I saw the inclusion of SOME SKV89 data in this spreadsheet:

https://docs.google.com/spreadsheets/d/12jj1A6PNjHmWbFNu0FSisEztir7izxAh...

from this thread:

http://budgetlightforum.com/node/69805

compiled by fneuf.

But it seemed that fneuf only included measurements that included R12 data (it factors into his “grading” formula) so most of the SKV89’s data is not included. (R12 was measured for only 3 out of 34 products)

Joshk
Joshk's picture
Offline
Last seen: 1 hour 2 min ago
Joined: 09/09/2015 - 12:12
Posts: 2472
Location: USA

CRI_Grade was created by me, I added it to his spreadsheet for him. It uses Ra, R9, and R12. It really targets the weak areas of modern LED technology works stellar. There is a link in my signature about it.

SKV89
Online
Last seen: 10 min 37 sec ago
Joined: 12/10/2017 - 12:46
Posts: 4117
Location: US
sac02 wrote:

SKV89,


 


I took the liberty of putting your data in a spreadsheet (google sheet).


 


High CRI LED light strips (and a few bulbs)


 


Maybe you can add the link to your OP?


 


If you want to be an owner of the spreadsheet to make edits, PM me.

Thanks! I added it to the OP

Jerommel
Jerommel's picture
Offline
Last seen: 5 months 1 week ago
Joined: 01/04/2014 - 13:18
Posts: 6380
Location: the Hague, Netherlands

snakebite wrote:
not good with variations in led vf and drop due to length.
the ones closest to the feed will be overdriven.
the resistors relieve this.
Jerommel wrote:
Meh, bypass the resistors with solder blobs and use a real driver for the lengths you cut yourself.

Never caused me any problems, but i do tend to underdrive them.
YMMV, as they say.
Curious
Offline
Last seen: 18 hours 38 min ago
Joined: 10/22/2020 - 07:04
Posts: 6

I’m totally new here. Where can I find explanations about all those parameters?

Joshk
Joshk's picture
Offline
Last seen: 1 hour 2 min ago
Joined: 09/09/2015 - 12:12
Posts: 2472
Location: USA

It’s a good question, I just don’t have much time to type. Maybe this along with google will help… CCT is the warm/cool choice you have. DUV is unwanted tint shift, usually green or rosy. CRI is a measure of the how balanced the rainbow is, under 90 is not very good. R9 is one of the rainbow measurements, it’s the hardest with modern tech, it is usually far lower than 90.
The others are a bit harder to explain in a short amount of time. I hope this helps.

Curious
Offline
Last seen: 18 hours 38 min ago
Joined: 10/22/2020 - 07:04
Posts: 6

Thanks Joshk.
Which parameter is relevant for blue light level? I guess that low CCT and an even spectrum mean low blue light but is there a more direct measure of it? Do you have a definition of the blue peak value and typical values for incandescent bulb, for example. Google didn’t help me with that.

SKV89
Online
Last seen: 10 min 37 sec ago
Joined: 12/10/2017 - 12:46
Posts: 4117
Location: US

In general, the higher the CRI, the lower the blue wavelength because the phosphor needs to convert more blue wavelength into other wavelengths to achieve the high CRI. Of course lower CCT means lower blue light because more blue light needs to be converted in order to achieve the lower CCT. But you never know unless you test them. You can compare the blue peaks in the ones I tested.

Joshk
Joshk's picture
Offline
Last seen: 1 hour 2 min ago
Joined: 09/09/2015 - 12:12
Posts: 2472
Location: USA
Curious wrote:
Thanks Joshk. Which parameter is relevant for blue light level? I guess that low CCT and an even spectrum mean low blue light but is there a more direct measure of it? Do you have a definition of the blue peak value and typical values for incandescent bulb, for example. Google didn’t help me with that.

The 460nm “blue peak” of a 2700k LED bulb is about 1000x LESS than the sun at noon today. “blue fear” mostly comes from shady salesmen and click-bait writers.

Joshk
Joshk's picture
Offline
Last seen: 1 hour 2 min ago
Joined: 09/09/2015 - 12:12
Posts: 2472
Location: USA

To better quantify what I am saying, The sun is putting out 2000mw/m2 of 460nm blue light right now. My 2700k LED bulbs put out 2mw/m2. My meter was in relative mode back when I was testing cool-white bulbs, so I don’t know the numbers for them right now. Factory defaults… Tired

Curious
Offline
Last seen: 18 hours 38 min ago
Joined: 10/22/2020 - 07:04
Posts: 6

Thanks for the answers. Just to be sure – is it true that whenever the blue peak is low and the spectrum is similar to incandescent light there will be not much UV? So there’s no need for getting a separate UV measure?

Joshk
Joshk's picture
Offline
Last seen: 1 hour 2 min ago
Joined: 09/09/2015 - 12:12
Posts: 2472
Location: USA

Yea a quality 2700k LED bulb will look incredibly similar to a 2700k incandescent to your eye. The meter will know the difference though. LEDs get away with the difference so well because our sensitivity to light drops off bad out where the LEDs drop off. Honestly, I think we (humanity) has the tech to fill the graph a lot better, it’s just not worth the extra power and heat to do so.

2660k Incandescent bulb:

2600k LED bulb:

There are some specialty LEDs that use a UV emitter (I think user Sunlike sells one), but I have never seen a second seller of them.

Pages