Blog - All Comments

RE: Phasing out fluorescent tubes: Moving to sustainable lighting solutions

DAB — Wed, 26 Jun 2024 20:34:30 GMT

Yes, I have many fluorescent bulbs and fixtures needing replacing in my basement and house.

Amazing, some still work after over 37 years.

RE: Does CRI matter in horticulture?

beacon_dave — Wed, 05 Jun 2024 21:28:42 GMT

Broken links look like they should be:

Light Measurements in Horticulture:
https://www.rs-online.com/designspark/light-measurements-in-horticulture

What is CRI (Colour Rendering Index)?:
https://www.rs-online.com/designspark/what-is-cri-colour-rendering-index

RE: Does CRI matter in horticulture?

DAB — Wed, 05 Jun 2024 20:13:17 GMT

Your links do not work.

RE: 10 Common LCD, OLED and TFT Display Questions

DAB — Wed, 29 May 2024 20:19:41 GMT

Nice overview.

RE: Learn about Controlled Environments in Agriculture (CEA)

DAB — Thu, 16 May 2024 19:46:07 GMT

Though costly, you get much better control over the quality and production.

Given a limited amount of good land for growing food, especially around urban areas, I can see the benefits for keeping a ready food supply available locally.

Also, if we are ever going to explore our solar system, we will need this technology for long duration space missions.

RE: Learn about Controlled Environments in Agriculture (CEA)

rsc — Wed, 15 May 2024 18:59:30 GMT

When I was looking into purchasing some LED grow lights locally, the cost was about $1 per watt. Kind of high for a small greenhouse.

RE: Interesting facts about ultraviolet (UV) light

DAB — Thu, 09 May 2024 18:23:17 GMT

It is too bad that UV cameras are so expensive.

There is an amazing world only visible in UV.

RE: How LEDs have changed the world

DAB — Sat, 27 Apr 2024 18:54:58 GMT

Yes, the LED has made indication, and illumination much more efficient over the old Edison filament type lights.

RE: Vertical farming - Where to start?

DAB — Thu, 18 Apr 2024 21:11:19 GMT

One advantage of this farming method is that you can better control the evapotranspiration rate of the crops by controlling the humidity and temperature.

RE: LED dimming with Pulse Width Modulation (PWM)

DAB — Thu, 11 Apr 2024 20:15:21 GMT

You have two things working for you in PWM.

First, your eyes respond logarithmically to the light pulses.

Second, you have persistence, which allows the brain to see the light even after it has gone out.

RE: Why use horticultural LED grow lights?

DAB — Thu, 04 Apr 2024 18:32:41 GMT

I am curious, have there been any long term studies on the effects of these lights on people?

Specific wavelengths may be great for plants, but some people are very sensitive to specific wavelengths of light over time.

RE: What is CRI (colour rendering index)?

DAB — Tue, 26 Mar 2024 18:50:32 GMT

Yes, if you want correct color, you need to calibrate your lighting source and the sensor you plan to use to record the information.

When I began using cameras back in the 1970's we spent a lot of time looking into light purity, distribution and reflective effect on camera sensors.

These efforts got even more interesting when I move into multi spectral and then hyper spectral sensors.

RE: LED optics: lenses versus reflectors

DAB — Thu, 14 Mar 2024 18:59:16 GMT

There is a loss of transmission through lenses.

We used to estimate about 6% loss per glass element.

I do not know if the plastic lenses have similar characteristics.

RE: Full spectrum light in horticulture

DAB — Tue, 05 Mar 2024 20:15:48 GMT

Your information contradicts other posts on this subject.

Do you have any hard data showing specific plant growth with the full spectrum verses spot spectrum lights?

RE: Light Measurements in Horticulture

DAB — Tue, 27 Feb 2024 19:19:02 GMT

Yes, for specific plants, the frequency of light matters.

If you match up the proper light frequencies you get a much better crop yield.