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Katchupoy

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For the past few weeks, I've been doing my extensive research on lighting.
I hope that this will help me become smarter in choosing the next light upgrade I am going to buy. And also hoping that this will help also people out there who are in the same situation I have right now.

Actually, I've narrowed down my research to all Sanjay Joshi's work.
More of his work can be found on the links below...

1) http://www.reeffrontiers.com/forums/showthread.php?t=71
2) http://www.advancedaquarist.com/index.htm

and also here.

3) http://www.cnidarianreef.com/lamps.cfm
4) http://www.reeflightinginfo.arvixe.com/

I am almost done, and will be posting some acquired data from different sites mentioned.

But I need your help. Ineed one more data. If anybody out there has the Steve Tyree graph of the Photosynthetic Requirements of corals...

I believe that some who attended bought the book and the CD. If you can email me the "GRAPH" that would finish up my research.

I've search everywhere but cannot find it. Maybe you know a link or something that you can share... I appreciate it.

What I'm looking for is the spectral anakysis of the coral..... and not the light. He used this same graph to map his findings on different light spectral analysis.

Thanks.
 
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Katchupoy

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Yes, thats the same one he presented here in Seattle two weeks ago. If someone out there bought the CD. Maybe you can email me the graph that explains how he match different 400 watt bulb against the photosynthetic requiremtns of different algae.

Thanks in advance.
 

Katchupoy

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Definition of terms...

Ok, while Im waiting for somebody to email me the graph... I will continue this thread by starting with definition of terms...

Definition of terms:
TEXT AND DIAGRAMS BY SANJAY JOSHI AND DAVE MORGAN

Please click here for more information

Radiometry - is the measurement of quantities associated with radiant energy
- it is used when we are interested in the radiant energy for the purpose of spectral analysis and photosynthesis

Photometry - is the measurement of radiant energy in the visible range (380 nm to 770 nm) evaluated in terms of a human visual response (rather than the response of photosynthetic organisms).
- are used when we are interested in the visual stimulation aspects of radiant energy.

PAR - photosynthetic available radiation (PAR) is defined to be the radiation in the 400 nm to 700 nm waveband

PPFD - When measured in photon terms, PAR is also called Photosynthetic Photon Flux Density (PPFD), which is a measure of the number of photons in the 400 nm to 700 nm waveband that are incident per unit time on a unit surface

NOTE : Different light sources with identical PAR can have very different spectral distributions. The independence of PAR and spectral distribution is the reason we must consider spectral distribution data as well as PAR data when we compare lamps.

CCT - Correlated Color Temperature (CCT)
- Color temperature refers to the spectral distribution of light radiated from a black body as it is heated. A black body is an ideal object that absorbs all light incident upon it. This complete lack of reflectance implies that the apparent color of a black body in no way depends on the light that falls on it; a black body gets its apparent color only from the light that it radiates. This visible light radiated by a black body changes from red to blue to white as the temperature of the object increases. The color temperature of the light emitted is expressed as a temperature on the Kelvin scale, and corresponds to the temperature of the black body at which the light is emitted. This is known as the black body model.

CRI - Color Rendition Index (CRI)
- Color rendering index (CRI) indicates how much a lamp will cause an object to shift in perceived color compared to its color under natural light of the same CCT. CRI numbers range from 100 (no color shift) to 0 (black and white). For the purpose of analyzing the light sources available for lighting aquaria, the spectral distribution is the most important piece of information, because all radiometric and photometric quantities can be derived from it.
 
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Katchupoy

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Lets continue...

Note that all my data are taken from Sanjay's website. The only difference is Im going to present it to you all in all in one page. So you dont have to go up and down or next page to analyze the results.

Sometimes, we ask...

1) How much big difference is it really between 250 watt and 400 watt?
2) Is it worth it to do 400 watt or we can do it at 250 watt?
3) How about those 20k's compared to 14k's and 10k's
4) How about 400 watt 20k against 250 watt 10k

Well, I hope I can help you answer that questions.

JBNY did a magnificent work on the 250's but what about matching it against the 400's.
 
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Katchupoy

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Let analyze these images.



and




Maybe Im the only having problem but I'm having issues looking at the graph specially if the units on the left side is different. And this is true to all of the graph used.

So to solve this problem is to re-graph the spectrum. Why do we need to do this? So we can compare it side by side and relate to it I guess....
 
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Katchupoy

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Lets start with a 175WATT AB 10k and a 250WATT DE HQI AB 10k. Using the same scale.







What do you think?
Not much difference?
Notice the PPFD?
How about the CCT or Kelvin?



Lets add two more bulb...
250 WATT USHIO 10K SE and 250 WATT IWASAKI 6.5K SE





Lets drop everything except IWASAKI... and add two more...
250 WATT XM 10K SE ON ICECAP and
250 WATT XM 10K SE ON PFO-HQI




And the last graph for this test is adding 400WATT 20K RADIUM SE






.

.
 
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wanareef

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Aug 26, 2003
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Portland, OR
Ceasar

Looking good. I'm running a Iwsaki on a 250w dual PFO HQI with a XM 10k side by side and it looks the same - but then my eyes can't see without glasses anyway.

Can't remember, but somewhere in Sanjay's notes the 250w HQI put out better than the 400w se I remember reading. But since the 400w is available in DE that may have changed??
 
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