Upper Leaves yellowing and turning black

My plant is 1 month into flowering and is doing great. Just the fan leaves on the upper part of the plant started yellowing when I put it under my 1,000watt hps, but within the last 3 days or so though, the leaves started turning black. This also is affecting fan leaves in the green lower part of the plant that isn't part of the yellowing upper part. It almost looks like black mold in the way it forms in the leaves. ( I know for sure it is not black mold though, It's actually just part of the leaf's color ) Some have only a few dots, while others are almost all black. Any ideas what could be the cause?

Should I get a picture or is this enough of a description to make a diagnosis? I have a weed bible with nitrogen deficiency n magnesium deficiency pics but I do not believe they resemble this problem.

I'm leaning towards heat stress maybe just from the intensity of this crazy light?
The temperature is steady at about 80 degrees in the day, and light is about a 2 foot distance away, but it just still feels so crazy intense. Maybe I should turn my ballast down to 75% power and run at 750watts?

Always helps to post pics. Some strains will change colors late in flower, but if only the top leaves are effected it's probably heat stress. 1000w light should be at least 2.5-3ft away from the tops.