8800k or 6700k Daylinght bulbs?????

[Anonymous]

i was hoping to have that info for my own use, not pertaining to this thread. matt seemed very knowledgable so i asked.

 

[Luis]

Thank you for all your help guys, I've just got my bulbs. Thank you Matt for all your time explaining and clarifying this matter. Podman Time ago I read somewhere in the net what you are asking for, sorry I don't remember the http.

Once again thank you all.

 

[MattM]

...you wouldn,t have a breakdown of the different k values at different depths would you?

I have data on the drop off of various wavelengths (colors) with depth, but it's not corelated to color temperature.

I suppose a very rough guesstimate could be made, but it would be very inaccurate and misleading. Color temperature is a specific balance of color vs. intensity. The drop off of color with depth in water does not follow the same curve at all.

Here is drop off in water:

And here is color temp:

As you can see, the curve shapes are not similar. Furthermore, the peak wavelength of a given color temperature is different for different temps, but the wavelength that penetrates water the best is constant. Also note that the surface curve above (blue shaded area on the first graph) is a similar shape. The sun is a pretty good appoximation to a 5500ºK curve.

Finally, here is a typical metal halide spectrum for comparison. This is from one of Sanjay Joshi's articles in Aquarium Fish. See how well the "5500ºK" bulb matches the 5000ºK color temperature curve above? (Hint: the right answer is "It doesn't match at all! Not even close to any of them!")

Now you see what I mean when I say that color temperature does not even apply to metal halide lighting. Fluorescent is a similar story.

 

[Anonymous]

thats the best layman explanation i,ve gotten. thank you.