The Orchid House

Some data on commonly available fluorescent tubes

This is a bunch of raw data on the commonly available fluorescent tubes from GE, Sylvania and Philips.
                    Nominal   CRI     CCT   Notes
                    LPW (1)   appx    (K)
Daylight             65       75      6250  Bluish
GE Lite White        83.8     49      4200  Pale greenish
GE Cool White        78.8     62      4150  White
GE White             80       60      3450  Pale yellowish
GE Warm white        81.3     52      3000  Yellowish
GE SP41              82       70      4100  Pale Greenish, (2)
GE SP35              82       73      3500  Pale yellowish 
GE SP30              81.3     70      3000  Yellowish 
GE SPX41             84.3     82      4100  White 
GE SPX35             82.5     82      3500  White 
GE SPX30             81.5     82      3000  White (pinkish)
GE Chroma 50         55.3     90      5000  Sunlight on cloudy day
GE Chroma 75         50       92      7500  Northern clear daylight
GE Deluxe cool white 56.3     89      4175  White (pinkish)
GE Deluxe warm white 55       77      3025  Simulates incandescent
GE Sign white        60       82      5200  White (bluish)
GE Plant light       21.3     -2      6750  Purplish
GE Plant 
  and aquarium light 48.8     70      3050  Pale purplish
GE Natural           52.5     90      3700  Pinkish
GE SPX27              -       81      2700  Simulates incandescent

Old bulbs: lite white, cool white, warm white, sign white, plant light, white. Newer, wide spectrum bulbs: deluxe warm white, deluxe cool white, plant and aquarium light, chroma 50 & 75, sign white, natural, daylight. Newest, with REP: SP series, SPX series

The older bulbs tend to have spctra that are weighted heavily around green; it's not "spikey" but it's a rather sharp rise and fall. There is not a whole lot of difference between cool white and warm white. The latter has a specta that peaks more in the yellow (and therefore declines slowly through red) region, whereas cool white peaks earlier in the green and declines more through green than yellow.

The newer, wide spectrum bulbs have a much more even spectral output. It rises at 400 nM, peaks almost immediately, stays more or less level and slowly declines when it hits 650 nm. There are spikes, but they are at localized maxima at 400, 450, 550 and 575 nM.

The REP bulbs are the newest and may have been influenced by the energy crisis. They utilize rare earth phosphours, and produce more light per given quanta of energy than other tubes. Unfortunately, the spectra is kind of weird. It's very low and flat with two huge spikes, one in the yellow/red are about 620 nm and the other in the green at 550 nm. This is all but useless for growing plants, as these are primarily the two frequencies of light that are rejected by plants (they are green for a reason :-).


                                  Nominal   CRI     CCT   Notes
                                  LPW (1)   appx    (K)
Sylvania Incandescent fluorescent   39       89     2750  Simulates incandescent
Sylvania Warm white                 80       52     3000  Old technology
Sylvania Deluxe warm white          55       74     2950  Low efficiency
Sylvania Cool white                 79       62     4200  Bluish
Sylvania Deluxe cool white          55       89     4100  Low efficiency
Sylvania Interior design            82       69     3000  Warm tone
Sylvania Designer 3000              82       69     3000  More efficient than above
Sylvania Octron 31K                 90       75     3100  High efficiency
Sylvania Designer 830               82       80     3000  Royal white
Sylvania White                      80       57     3450  High efficiency
Sylvania Designer 3500              82       69     3500  Neutral white
Sylvania Designer 835               82       80     3500  Better CRI
Sylvania Octron 3500                90       75     3500  Good colour and efficiency
Sylvania Natural white              53       86     3600  Good color, fair CRI
Sylvania Octron 4100                90       75     4100  Good colour and efficiency
Sylvania Designer 4100              82       69     4100  Low tech (non REP) Octron
Sylvania Designer 841               82       80     4100  Better colour rendering
Sylvania Lite white                 86       48     4150  Efficient, poor CRI.
Sylvania Daylight                   67       76     6300  Blueish
Sylvania Design 50                  55       90     5000  Blueish
Old tubes: cool white, white, warm white, lite white. Newer wide spectrum tubes: deluxe warm white, deluxe cool white, design 50, daylight. The rest are the newer REP types. Sylvania has a product line predominently centered around industrial and domestic lighting.

(Note: Philips does not provide Lumens Per Watt information. Instead they provide a "relative light output" figure, which seems to be the percent of light (more or less) radiated than a cool white tube)

                                  Nominal   CRI     CCT   Notes
                                  LPW (1)   appx    (K)
Philips Agro-Lite
Philips Cool white                100        67    4100  Cool
Philips Cool white deluxe          70        89    4100  Cool
Philips White                     102        58    3500  Neutral
Philips Warm white                102        53    3000  Warm
Philips Warm white deluxe          68        79    3000  Warm
Philips Daylight                   83        79    6500  Cool
Philips Colortone 50               70        92    5000  Cool
Philips Colortone 75               64        95    7500  Cool
Philips Cool green                 83        70    6100  Cool
Philips Natural                    66        81    3400  Warm
Philips Soft white                 68        69    3000  Warm
Philips Lite white                103        51    4100  Cool
Philips Spec 30                   103        70    3000  Warm
Philips Spec 35                   103        73    3500  Neutral
Philips Spec 41                   103        70    4100  Warm
Philips Ultralume 27              105        82    2700  Warm
Philips Ultralume 30              105        85    3000  Warm
Philips Ultralume 35              105        85    3500  Neutral
Philips Ultralume 41              105        85    4100  Cool
Philips Ultralume 50              105        85    5000  Cool
Philips Advantage X 30            117        80    3000  Warm
Philips Advantage X 35            117        80    3500  Neutral
Philips Advantage X 41            117        80    4100  Cool

Old tubes: white, warm white, cool white. Newer wide wpectrum tubes: natural, colortone. Newer REP tubes: Ultralume, advantage, spec (?)

It's hard to imagine why Ultralume 50's are so well respected. They have a horrible output spectra, flat, low, with a small peak in the violet blue range at 430 nm, a huge peak in the (useless) green range of 540 nm and another peak in the 620 nm red range. They look VERY much like a gro lux with the green thrown in for CRI correction. The Ultralume 30 is a bit better; at least the red spike is bigger than the green spike, but the real winners are the colortone 30 ("warm", or spectra biased towards red) and the colortone 50 ("cool" or bluish). These have very nice wide spectra.

(1) Lumens per watt applies to the F40 type.

(2) REP = Rare Earth Phosphours

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