light penetration of 4 mil clear plastic?

I made a hoop house greenhouse out of pvc and 4mil clear-transparent plastic from lowes. But today I got to thinking, "How much light actually gets threw this stuff?" Anyone know?

Been about 20 years since I have had Greenhouse no to mention I was looking at building some greenhouses this year. overpaid on my new house, so that's out the window, but...... I did do quite a bit if research on coverings.

I was gonna use a 6 mill opaque ( not see thru) poly that has a LT ( light transmission) of 78%, so a 4 mil clear has to be like 90% + . you 'll do fine.

as long as you dont get too much weather .. 4 mils pretty thin IMO. If you don't get many winds in your area,You're good for the year (maybe two). but that's for next time you skin..

here's a link to a site selling poly @ 6 mil with an LT of 91% ( which seem pretty standard)

4 year 6 mil CLEAR Greenhouse Film Large Sizes | Growers Solution

drop cloth plastic will transmit less light then greenhouse film, my experiance is that youll have alot of nice tops, but after going thru the plastic, and then the canopy, theres little left after that so youll wanna trim of all the popcorn early