How to Estimate K-value?

[reefer1]

Hi Lighting Experts,
I wanted to get an idea on how to estimate the K-value of an adjustable LED light.
I have a Maxspect 16,000k LED light fixture with A (whites) and B (blues) channels. It seems that the 16,000k rating is with 100% A and 100% B. I tend to like more B channel because it makes some of my corals pop. However, I was recently told that I need more A (whites) to bring out some of the colors on my sps.
This got me thinking, is there a way to estimate K-value? For example something along the lines of:
A_per x 10,000k + B_per x 20,000k
where A_per and B_per are the percent settings for the A and B channels

Thanks

 

[mcarroll]

Isn't K a measure of friction – the "reynolds number"?

I'm not sure what you're after.....maybe PAR or lux? If so, a $10-15 light meter will help.

You may appreciate this: Beginner’s Lux

 

[reefer1]

K is a measure of the color temperature.
Here are some standard values form wikipedia and a graph to illustrate
6500K Daylight, overcast
6500 – 9500K LCD or CRT screen
15,000 – 27,000K Clear blue sky

 

[mcarroll]

As in "Kelvins"? "K" belongs to too many equations.

"Correlated color temperature" may be the term you want in that case....or just CCT or "color" for short. I think most folks here just say color.

The few meters I've tried do not accurately measure color as blue as we use (maybe just due to lack of calibration since they're made for Real Life, not reefing) but you can find color meter apps on your app store. You might find one that works! Some light meter apps that are more general purpose will also measure color. (Sorry I don't have any specifics to recommend though.)

@saltyfilmfolks might have some more/better ideas!

 

[saltyfilmfolks]

kelvin. Degrees Kelvin.
And no, most folks are just making it up and usually don’t know.

Just set the color to the way you like it. Yea, you need some white but..

The blue in the maxspect is actually pretty broad compared to say an ai prime blue or a Chinese black box channel.

Choose the color and set the intensity and time.

I have that Light btw.

 

[saltyfilmfolks]

As in "Kelvins"? "K" belongs to too many equations.

"Correlated color temperature" may be the term you want in that case....or just CCT or "color" for short. I think most folks here just say color.

The few meters I've tried do not accurately measure color as blue as we use (maybe just due to lack of calibration since they're made for Real Life, not reefing) but you can find color meter apps on your app store. You might find one that works! Some light meter apps that are more general purpose will also measure color. (Sorry I don't have any specifics to recommend though.)

@saltyfilmfolks might have some more/better ideas!

Lol.

Most of the leds produce so much blue it makes the color meter malfunction, even ones that claim to be 16k native.
I honestly don’t recall what my maxspect color tempted at.

 

[reefer1]

Hi saltyfilmfolks,
What settings do you have for channel A and B?
And do you have any rainbow tenuis such as the Walt Disney? If so, how do the colors look?
Thanks

 

[saltyfilmfolks]

Hi saltyfilmfolks,
What settings do you have for channel A and B?
And do you have any rainbow tenuis such as the Walt Disney? If so, how do the colors look?
Thanks

I’m running all SB Reef Light right now. The maxspect is in the basement.

IMO, and I can give you references , just set the color to the way you like it , and set the intensity and time correctly.

Low pigmentation can be a result of low nutrients or lower light. You’ll get better growth at Lower pars (350 for 10hrs approx) but with some you’ll get better pigment with higher pars or time.

Are you having a specific problem?

 

[mcarroll]

Lol.

Most of the leds produce so much blue it makes the color meter malfunction, even ones that claim to be 16k native.
I honestly don’t recall what my maxspect color tempted at.

I think I remember seeing someone mention that Maxspect's color claim was actually correct...not sure where I saw that however.

And I failed to ask @reefer1 why they were curious about computing the number? "Curiosity" is a perfectly fine answer, but I don't know of any practical use that the number could have so I'm curious if there is one.

 

[saltyfilmfolks]

I think I remember seeing someone mention that Maxspect's color claim was actually correct...not sure where I saw that however.

And I failed to ask @reefer1 why they were curious about computing the number? "Curiosity" is a perfectly fine answer, but I don't know of any practical use that the number could have so I'm curious if there is one.

Common question actually , and a good one.

 

[reefer1]

I started out researching why my WD colors have never been close to what I have seen online. My WD is fully encrusted to about the size of a half dollar with crazy polyp extension. (Not much branching but this may be because my PAR is so high.) My WD is fairly pale (light blue) without any real colors or any pop.
My nitrates are about 5ppm (so I have some nutrients in my system) and the LUX meter shows a peak of 42,000 lumens at the water surface. (I think this is about 650-700 PAR.) The WD sits about 4-5 inches below the surface. I run A=40%, B=80%.
Someone mentioned elsewhere, I need more white (A) to bring out the WD colors.

My interest in estimating the k-value is a combination:
(a) being curious and
(b) seeing how far off I am from the 16,000k the Maxspect is rated at.

 

[mcarroll]

my WD colors have never been close to what I have seen online

Judging anything like that from pictures online is a non-starter. Check this out: “DSLR Camera” – The Internet Reefer’s Decoder Ring

What are your PO4 levels and how are you running this system? Also how old is it?

 

[saltyfilmfolks]

Well, the quick search has them at 250 to 500 par under every color temp on the planet. Lol.

The big WD thread if you haven’t seen it.
https://www.reef2reef.com/threads/walt-disney-tenuis-grow-out-thread.210024/page-15

 

[AdamNC]

You may be running low on your %. I used to run ch1 65% ch2 90% on the 16k and I had good growth and color. Deep blue/purple, bright orange and greens. Im now using the RSX am at ch1 90% ch2 70% ch3 70% ch4 90%.