Eidetic Imagery; NOT Eidetic Memory... Mendelssohn? Mozart?

In a recent documentary I watched on the saga of Thomas Edison and Nicola Tesla, the issue of the eidetic imagery of Tesla came up by way of some of the examples which came storming out of the mind of Tesla.
Briefly: Tesla was an  electrical and mechanical engineer and an inventor; all wrapped up neatly in one human package. Tesla was a contemporary of Edison, and worked for and with him for a period of time. Tesla  became an opponent of the fabled inventor by way of his championing alternating  current as the reigning core of electrical transmission, chiefly in commercial modality. Edison believed in direct current as the superior core; and so the two inventors became foes. History has proven Tesla correct, obviously.
What is engrossing is the parade of lurid  images that formed consistently in Tesla's mind - some were such images as the transformer, let alone the overwhelming advantages of alternating current, both of which entered the outside world AFTER the images scurried across the mind's eyes of Tesla - arguably among  the most compelling examples of what we call futurism.
What came to mind while watching this documentary was the name Da Vinci, and his sketches of objects which were burned into his mind long before they came into existence.
And Mozart's statement "I can see an entire symphony on the head of a pin."
And Mendelssohn, at age 17, beset by the need to write his "Midsummer Night's Dream" in an incredibly short time, after having read, in both English and German,  Shakespeare's masterpiece. It is  of  really deep interest to me, what with the  numbers of Mozart's youthful miracles available, that Grove called the  Mendelssohn  overture  "the greatest marvel in early maturity that the world of music has ever seen."
Again Mozart - "The music? It is already here. All that is needed  is to write it down."
There are many statements available dealing with eidetic memory; for instance, Mozart being able to memorize an entire composition upon one hearing, as were Mendelssohn, Rachmaninoff and Bernstein; to cite other examples.
But there seems to be more written about eidetic memory than the specific, separate issue of  eidetic imagery. Am I  mistaken?
 To be sure, photographic memories are indeed among the most impressive examples of human gifts.
But; for me - brilliant, deeply etched images created before they  enter Reality  - 
Charles Ives, in his "Unanswered Question," coping with the three issues of existential interrogation - "Who Am I? What Am I? Why Am I Here?"
The first  two questions beguile me, especially...