Glass too thick?

Hi,

Need some advise here!

I have a euro wing reflector, i have now diy'd a glass pane on to it between the lamp and plant.

/the glass is 7mm thick heat resistant, being so thick is their going to be any negative effacts? I.e, stopping a lot of light comming through?

+reps for help.

Yes, it will restrict the light, to some extent, and the thicker it is, the more restricted it will be. All air-cooled reflectors, have this problem. There's no preventing that. As to knowing how much it's being restricted, I imagine there's a complex formula somewhere to determine this, or...you could pick up a $30 light meter off Ebay, and test it yourself.lol