Lighting ratings

[Playdope]

Hi all,

I was wondering if anyone could give me the approximate level in units of micromols/m^2 x s

M. Halides:

Power compacts:

VHO:

I have a Li-Cor Quantum Sensor that measures in those units, but I don't have the lights. If you have a better way of answering my odd question, please do so.

I am really only looking to have a comparison of the outputs of the above forms of light, and it would be nice to see that rating in the units of my sensor.

Many thanks,
Jon

 

[c0yote]

Lamps are rated in lumens (light output) and are usually listed on the lamp. What you're measuring is illuminance (how much light is at that location) and is dependant on the distance from the light source, efficiency of the lamp reflector, etc.

 

[Playdope]

Thanks for the info.

So how do you think I could best explain to someone the difference in heat and light output of the above types of lamps.

It sounds like comparing lumen levels would be a good way to compare their light output, but how about comparing their heat output.

Jon

 

[Playdope]

I was instructed to find an approximate conversions between lumens and standard scientific lighting units. Anyone?

Thanks,
Jon

 

[-JB]

You have a Quantum sensor it is used to measure PPFD (Photosynthetic Photon Flux Density). The units for PPFD are µEinstein/m2/s or µmoles/m2/s.

PPFD is used to measure PAR (Photosynthetically Available Radiation). The range of the lighting spectrum in which photosynthesis occurs in plants. It is a much better way of measuring lighting used on our tanks. In measure PAR the light irradiated between 400-700nm is treated uniformly as opposed to lumens where the light is weighted according to how the eye sees them (the human eye is more sensitive to greens and less sensitive to blue and red).

 

[-JB]

To give you some frame of reference. An Iwasaki bulb run on a PFO standard ballast with no reflector, puts out about 705 PPFD at 8". Or would have a PAR rating of 705.

HTH

 

[Playdope]

Many thanks for the response!

Jon