What is the perfect temp for the highest leaves to be at?

I'm trying to figure out my setup. I'm new to this. I have plenty of air flow and the temp has been 73-77 the last 48 hrs. my leaf temperature is sitting at 81, but they seem perfectly fine. My question is what is the perfect temp for the actual flora to be at under the light, or what is too high? I'm trying to get my air flow and light height adjusted for best efficiency.

dude, use ur hand, if you hold the back of ur hand to the light source at the canopy top for a minute or so and you can feel that there is no threshold for the heat increase, you have a problem.

78.2943840368494 degrees.

Throw a fan in there pointed above the plant canopy towards the light. It will help bring the temps down and replace the co2 around the leaf surface. I don't see issues until I get above 84 degrees.