This photo is in my opinion Nitrogen deficiency, but why are the tips burned resembling a nutrient burn? Does late-stage nitrogen deficiency have burned tips? Or does late-stage nutrient burn cause a nutrient lockout, meaning that nutrients cannot be taken by the plant?
When you ask questions it's best give as much detail as possible in your explanation.
For example- "I'm having such n such problem"
Then whatever pictures ( in natural light)
I'm using a 750w mh, 85f day 83f night 75% rh day 75% rh night @1500ppm. I have these plants (list plants/age/strain/breeder) , and I am having such n such issues.
It's always best to give a detailed explanation so we can help you as fast/accurately as possible. :)