D3monic
Well-Known Member
Scored a Haight PPF-800 on craigslist for only $150. Things damn bright but I wanted to know what the PAR Values where so I borrowed our reef clubs meter.
Quick definition for anyone who may no know what PAR means.
"PAR (Photosynthetically Active Radiation) is the quantum measurement of Photosynthetically Active Radiation per unit area, or the number of photons in the 400-700 nm from green to range collected per unit area, during a unit of time. PAR is typically expressed in Microeinstein per second and square meter (µE m[SUP]2[/SUP] s[SUP]1[/SUP]).A Silicon Pyranometer is instrument most often used to measure irradiance over a defined wide range (300 to 1100 nm) of spectra (including infra-red and ultra-violet). Irradiance as measured by a silicon pyranometer is typically expressed in W/m[SUP]2[/SUP](watts per square meter)." -google
Again the fixture is a Haight ppf-800 180 watt with 32- 6 watt LED's
The fixture has a high and low setting for each color. (except the couple white) I took readings with all Low, one on high and both on high. Readings where taken center of light under a LED.
Low MID MAX
1" 380 740 1188
2" 300 500 580
3" 253 385 480
4" 220 296 420
5" 215 268 372
6" 188 240 328
7" 166 214 273
8" 144 190 215
1' 97 135 150
Now the Million dollar question. Whats a good range to be in at the top of plants? and how does this unit compare to others in a similar wattage?
Unfortunately as you get out from the edge of the fixture the values drop drastically to almost nothing until you get down to at least a foot. Even then the spread isnt enough to light the entire box well. I would need to be at least 14-16" above plants to light the entire thing. But then the outside edges would only be getting around 20 micromoles.
Thoughts? Lighting gurus?
Quick definition for anyone who may no know what PAR means.
"PAR (Photosynthetically Active Radiation) is the quantum measurement of Photosynthetically Active Radiation per unit area, or the number of photons in the 400-700 nm from green to range collected per unit area, during a unit of time. PAR is typically expressed in Microeinstein per second and square meter (µE m[SUP]2[/SUP] s[SUP]1[/SUP]).A Silicon Pyranometer is instrument most often used to measure irradiance over a defined wide range (300 to 1100 nm) of spectra (including infra-red and ultra-violet). Irradiance as measured by a silicon pyranometer is typically expressed in W/m[SUP]2[/SUP](watts per square meter)." -google
Again the fixture is a Haight ppf-800 180 watt with 32- 6 watt LED's
The fixture has a high and low setting for each color. (except the couple white) I took readings with all Low, one on high and both on high. Readings where taken center of light under a LED.
Low MID MAX
1" 380 740 1188
2" 300 500 580
3" 253 385 480
4" 220 296 420
5" 215 268 372
6" 188 240 328
7" 166 214 273
8" 144 190 215
1' 97 135 150
Now the Million dollar question. Whats a good range to be in at the top of plants? and how does this unit compare to others in a similar wattage?
Unfortunately as you get out from the edge of the fixture the values drop drastically to almost nothing until you get down to at least a foot. Even then the spread isnt enough to light the entire box well. I would need to be at least 14-16" above plants to light the entire thing. But then the outside edges would only be getting around 20 micromoles.
Thoughts? Lighting gurus?
