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Old 01-19-2018, 05:23 AM #7151
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so, is there any consensus in what color temperature is better overall: 3000K or 4200K? Also, does higher CRI have any beneficial effects over lower 80 CRI?

looking at this chart (if it's accurate) i'd say 4200 is better since it has more spikey red around 650 nm, less pronounced yellow/orange and more blue, while 3000K has huge spike around 680, more orange and less blue. i may be mistaken but 680 isn't that good at all, is it? seems closer to IR than usable light.
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Old 01-19-2018, 01:32 PM #7152
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In regards to colour temperature, most people are using the 3000 for flowering, and the 4200 for vegging.

Having said that on CMH fixtures that have two bulbs some people in flowering are using one of each bulb to get a varied spectrum in flowering.

In regards to the CRI indexing, the higher the number the closer the light spectrum is to the sun. The sun would be at 100.

Most CMH lights I see are anywhere from 91 to 96.
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Old 01-20-2018, 06:05 AM #7153
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Quote:
Originally Posted by Nirrity View Post
so, is there any consensus in what color temperature is better overall: 3000K or 4200K? Also, does higher CRI have any beneficial effects over lower 80 CRI?

looking at this chart (if it's accurate) i'd say 4200 is better since it has more spikey red around 650 nm, less pronounced yellow/orange and more blue, while 3000K has huge spike around 680, more orange and less blue. i may be mistaken but 680 isn't that good at all, is it? seems closer to IR than usable light.
Dunno about consensus but I figure Philips did their homework in creating the 930 agro lamp for horticulture. They have scientists. I'm just some guy who grows his own weed...

Any of their 315 lamps is a great choice. I'll stick with their lamps, in part because they appear to have twice the rated life of the competitors but don't cost twice as much...
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Old 02-12-2018, 02:09 AM #7154
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Quote:
Originally Posted by Nirrity View Post
so, is there any consensus in what color temperature is better overall: 3000K or 4200K? Also, does higher CRI have any beneficial effects over lower 80 CRI?

looking at this chart (if it's accurate) i'd say 4200 is better since it has more spikey red around 650 nm, less pronounced yellow/orange and more blue, while 3000K has huge spike around 680, more orange and less blue. i may be mistaken but 680 isn't that good at all, is it? seems closer to IR than usable light.
Using CRI in horticulture industry is a mistake. CRI is a scale of 0-100, it is used to describe how accurate a light source renders color of an object.The higher the CRI, the better the color rendering ability. Plants don't need high CRI light to render their color.
The most important criteria is SPD, then the relative strength of different wavelength lights, the last is PPF.
Philips 3000K and 4000K bulbs are full spectrum, both can be used for veg and flower. If you have a 400W dimming CMH ballast, better to use 4000K bulb.
https://www.facebook.com/SunPlix/pho...type=3&theater
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Old 02-13-2018, 02:10 AM #7155
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Is this
BaddAss Low Frequency Ballast 1000w
Compatible with this
Philips 421784 - CDM860/V/O/4K/BT37 EA
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Old 02-21-2018, 06:53 AM #7156
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Originally Posted by CMH View Post
Using CRI in horticulture industry is a mistake. CRI is a scale of 0-100, it is used to describe how accurate a light source renders color of an object.The higher the CRI, the better the color rendering ability. Plants don't need high CRI light to render their color.
The most important criteria is SPD, then the relative strength of different wavelength lights, the last is PPF.
Philips 3000K and 4000K bulbs are full spectrum, both can be used for veg and flower. If you have a 400W dimming CMH ballast, better to use 4000K bulb.
https://www.facebook.com/SunPlix/pho...type=3&theater

In LEDs, there's a difference in growth with different CRIs. High CRI is often created with higher amount of red in the spectrum.
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Old 02-21-2018, 07:45 PM #7157
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In LEDs, there's a difference in growth with different CRIs. High CRI is often created with higher amount of red in the spectrum.
Are you saying better growth with high cri in leds?
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Old 03-09-2018, 12:04 AM #7158
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Switched out 6 of my mag ballast 1k HPS's for 6 Ceramic Solutions 630 CMH DE lights with 3KR bulbs. So far so good, looking pretty even so far. Maybe a little more stretch with the HPS's.


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Old 03-09-2018, 12:43 AM #7159
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Quote:
Originally Posted by Nirrity View Post
so, is there any consensus in what color temperature is better overall: 3000K or 4200K? Also, does higher CRI have any beneficial effects over lower 80 CRI?

looking at this chart (if it's accurate) i'd say 4200 is better since it has more spikey red around 650 nm, less pronounced yellow/orange and more blue, while 3000K has huge spike around 680, more orange and less blue. i may be mistaken but 680 isn't that good at all, is it? seems closer to IR than usable light.
They're all excellent. OTOH, I have to respect the scientists at Philips who developed the 930 agro lamp. I figure it's the best of the bunch for plants or they wouldn't bother making it-

https://boulderlamp.com/315w-agro/
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Old 03-09-2018, 01:48 AM #7160
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our 2 315's came with hydro crunch bulbs- in our 4x3.5' tent, these '2' fixtures don't compare with our 1000w hps grows- the buds r way underweight- they def put out less heat, but the growth is underwhelming....
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