There is something to be said about the limitation of the human eye and its ability to see only certain spectrum of light. This is about the time where I delve into studying the human eye and its limitations and how certain entities are able to manipulate our field of vision so as to remain undetected. My entry into this study will be through "flicker fusion threshold" and the relation to frequency:
https://en.wikipedia.org/wiki/Flicker_fusion_threshold
"The flicker fusion threshold, or flicker fusion rate, is a concept in the psychophysics of vision. It is defined as the frequency at which an intermittent light stimulus appears to be completely steady to the average human observer. Flicker fusion threshold is related to persistence of vision. Although flicker can be detected for many waveforms representing time-variant fluctuations of intensity, it is conventionally, and most easily, studied in terms of sinusoidal modulation of intensity.
....
Different points in the visual system have very different critical flicker fusion rate (CFF) sensitivities; the overall threshold frequency for perception cannot exceed the slowest of these for a given modulation amplitude. Each cell type integrates signals differently. For example, rod photoreceptor cells, which are exquisitely sensitive and capable of single-photon detection, are very sluggish, with time constants in mammals of about 200 ms. Cones, in contrast, while having much lower intensity sensitivity, have much better time resolution than rods do. For both rod- and cone-mediated vision, the fusion frequency increases as a function of illumination intensity, until it reaches a plateau corresponding to the maximal time resolution for each type of vision. The maximal fusion frequency for rod-mediated vision reaches a plateau at about 15 hertz (Hz), whereas cones reach a plateau, observable only at very high illumination intensities, of about 60 Hz."
Follow up:
This is pretty much what is going on except that the human eye cannot see these entities in their true form, and to take it a step further they have covered their tracks by conditioning the human species with religion in which they are able to hide behind labels such as "fallen angels" or other terms.
The fact of the matter is that some, few, people have seen these entities in their true form, such as Neil Armstrong (or maybe it was Buzz, I can't remember at the moment). This 1983 movie is what I would consider a documentary on what is taking place on Earth (and very likely elsewhere too). The reason for the flat Earth psyop, to cover up this and related information:
V FINAL SEASON INTRO 1984 REPTILIANS ON THE MOON PREDICTIVE PROGRAMMING ADRENOCHROME:
https://www.bitchute.com/video/rMpLBpxrLrKY/
THE MOON MATRIX - THEY LIVE 1988 - THE REPTILIAN NET - 2011 FREQUENCY FENCE AROUND EARTH
https://www.bitchute.com/video/R23WtjhpyM3w/
Why was there two minutes of missing transmission between Apollo 11 and NASA?
https://www.bitchute.com/video/rMsSwxaUFFvy/
The answer to that question is here:
WILLIAM TOMPKINS SELECTED BY EXTRATERRESTRIALS PART 1 OF 2 PROJECT CAMELOT KERRY CASSIDY 2016:
https://www.bitchute.com/video/hIoKh7ntw60I/
How they are going off planet, the tech and hardware:
USAF CLASSIFIED BLACK BUDGET AIRCRAFT - SECRET SPACE PROGRAM MICHAEL SCHRATT - FEB 2017:
https://www.bitchute.com/video/CAMMdMNn0sER/
