in fact, if you put a luxmeter outside in the shade you will have more lumen than with a fluoro anyway and without burning the clone. But Zandor is right, outside you don't have 24/7 of light... I made ak47 clones outside like this, they've just rooted, but now they are flowering, they are 2 inches tall, i just wait and see, i will have tiny ak47 buds outdoor..
Fhydro