BigBill's "Tip Of The Day"!
You can can a pretty good read on light intensity by using just your hand and a sheet of white, printer paper. I think that everyone has access to paper and a hand.
Lay the piece of paper down, balanced on top of the orchid in question. If that does not work, hold it with your right or left hand over the orchid. How far over? The paper at the top of the plant, the hand about 12" above the paper. If your hand casts a shadow on to the paper that seems "fuzzy" or "out of focus", that is about 800-1000 foot candles. That is the proper level for most Phalaenopsis and other low light plants like Paphiopedilums.
If the shadow produced is better defined, darker, but not quite sharp or in focus, ie. the fingers look fuzzy and are not sharply defined, that is around 1,800-2,000 foot candles. Good light for terrestrial orchids, most Oncidium types, Miltonias, some Epidendrums, most Bulbophyllums smaller Angraecoids, etc.
If your hand casts a very well defined shadow that appears to be clear and in focus, that is around 3,000 foot candles. This is where most Cattleyas, Brassavolas, some smaller Vandaceous things like Neofinetia, Phragmipediums, Cattleya Alliance hybrids (the big standard size) etc. Smaller Cattleyas should fall in between point one and two.
This is a simple way to gauge the strength of the sun light or light in general. A good quality light meter is expensive, Cheaper light meters, under $200 or so are not very accurate.
And please remember this, that if an orchid has bloomed before, or your purchased it in flower and it hasn't bloomed again, the number 1 consideration is not enough light. You can fool around and adjust watering, humidity, air movement, all of the other razz a ma tazz but if the light is poor, the plant won't bloom. Orchids bloom with too much light. But not without the proper light intensity.
Raz a ma tazz is a very technical term in the orchid world!!!
