LPS

[FlowerPower]

hey people I was just reading a hydro book from the eighties, and it has a bit about lps and how they produce light only in a narrow portion of the spectrum (yellow/orange) I was curious as to whether this type of light would be suitable for use with a 400 hps son agro, for the flowering? :scratchin

[F420]

A Low Pressure Sodium light hardly has any good frequencies or colors and it has no power to push the light into the plants. In fact, if all you shine on a plant is a low pressure sodium light, the plant can die. This is only in case a low pressure sodium is the only light it gets.

 

http://www.3rlighting.com/tutorial/growlig...e%20sodium.html

 

Sodium vapour lamps as often used for street lighting produce almost monochromatic yellow light at 589nm from a low pressure discharge in Sodium vapour. These lamps are efficient but lack of red and blue wavelengths make them unsuitable for plant growth. Special starter circuits are required.

 

got to top High pressure sodium lamps produce an intense pinkish-white light with a colour temperature of 2050°K from an arc discharge in high pressure sodium vapour and are an efficient way of lighting large areas. Plants grow well under this light, but the colour cast may reduce acceptability for decorative illumination. The standard lamps are said to encourage production of flowers and fruit. Versions producing more blue light are available to promote compact vegetative growth, but this is not needed if the lamps are used to augment natural daylight which provides sufficient blue light.. Special starter circuits are required. Check that lamps will operate in a horizonal position if this is required.

 

Combined use of metal halide and high pressure sodium can be used as the emission spectra of the lamps compliment each other and promote normal plant growth.

 

http://www.succulent-plant.com/light.html

[FlowerPower]

I wonder how many people bought useless lamps.....

[Tom]

A few new growers start with the wrong lights, usually halogen or mercury vapor and they are a total waste of time. A 400w HPS running a Son-T-Agro is probably the best light for a new grower using a wardrobe or similar sized grow or 600w's for a serious grow room. What is your ventilation like, it plays just as important a part in growing as correct light does, it also needs to be very efficient for heat removal when growing with HID's.

[FlowerPower]

What is your ventilation like, it plays just as important a part in growing as correct light does

I have a 280mm exhaust fan (went through three of those DAF's before buying an ozzie made one), and four passive inlets, each about 3 1/2".....

[Tom]

Sounds good.