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My Light Meter
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Posted by maryeis z7NJ (My Page) on Fri, Oct 2, 09 at 22:53
I was given a light meter for the holidays last year and still am trying to figure it out.
It's a Hydrofarm Light Intensity Meter. It has two scales on it. One for "Sun & High Intensity" and one for "Fluorescent". Here is a picture of the meter in question: http://www.hydrofarm.com/pb_detail.php?itemid=3087# (click on picture to enlarge it)
As you can see it has two settings on the bottom...500 and 5000. I want to measure the fluorescent light so I use the 500 setting.
The problem is that I don't know what the needle is telling me when it goes to 35, 40, 45, etc. It says the numbers are 10X.
When looking up a plant there are recommended light levels and I want to be able to understand if I'm close to the levels needed, but I don't know what this device is telling me.
Example: African Violets have a max. foot candle hour recommendation of 37,500 and min. of 15,000. When my meter goes to 30(X10 =3,000 foot candles) and I'm lighting them for 10 hours, I think that equals 30,000 foot candle hours. Is this correct or am I missing something?
One more question: If I put my light meter where my plants will be and the measurement is higher than the max. recommended foot candle hours what should I do? Use less light or fewer hours?
Please Help!!!
Mary
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Follow-Up Postings:
RE: My Light Meter
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| Looking at the picture just multiply the number on the lower meter by 10 for fluorescent foot candle reading. Don't worry about the hours part of it. African Violets need about 1000 foot candles so your meter would read 100 at the best spot for your plants. Then just keep the light on about 12 - 16 hrs a day and you're all set. bioWheel |
RE: My Light Meter
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Thank you for your kind reply bioWheel. My problem is that my meter, on the fluorescent scale only goes up to 50 foot candles so when you factor X 10 it's showing me having 500 at the height of the top of plant.
You mention in your post that my meter would read 100 at the best spot. What if the scale only goes up to 50?
Just trying to understand this meter and what it's trying to tell me....lol. Mary |
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