User:Cprobertson1/Sandbox

=Optical woo= Notes on the prevalence of crank misunderstandings with how light works.
 * Check if perspective/refraction is covered by any other articles

Photography
Cranks seem to struggle with the idea of the camera (despite the first camera being made more than two centuries ago and practically everybody walking around with one (or more often, two) in their pocket practically all the time)

Differences between the eye and a camera
The biggest problems seem to arise from cranks not realising that cameras are not the same as the human eye! That last one can probably be trimmed down quite a lot as it is interesting but not necessarily relevant (though perhaps it should be moved into one of the proofs that the creator(s) of the human eyes aren't very good at it.
 * 1) Notes on the high dynamic range of the eye.
 * 2) Notes on the bad design of the eye (seriously, who puts their wiring in front of the sensor?)
 * 3) Notes on the blind spot of the eye (often claimed by cranks to not exist... despite it being a common thing done in classrooms)
 * 4) Notes on the error correction that the brain performs on vision (for example, colour perception is best in the fovea centralis (with around 160'000 cones per mm² quickly falling off to around 5'000-10'000 cones per mm² - the colour perception and apparent sharpness of human vision is much greater here (called "foveal vision") and the brain simply compensates for everything else. Rod concentrations are greater in the perifery, which is why soldiers and astronomers practice "averted vision" for better low light perception). The eye is also constantly darting around ("saccades", "smooth pursuit" and "vergence shifts") grabbing spot information of key components (especially faces and high contrast regions) and putting it all together into a mental model of what is seen.

Exposure

 * 1) Quick notes on the exposure triangle (bucket/bottle analogy)
 * 2) "Why are there no stars in this photo of the earth/surface of the moon" - because cameras don't have high dynamic range processing like the human eye does and can't correctly expose a dark area and a bright area simultaneously.
 * 3) Artifacts from long exposure - orbs (diffuse reflections), streaks (dust drifting past lens), and rods (insects) are misattributed to ghosts, ghosts, and aliens respectively.
 * 4) Noise (sensor noise, and compression artifacts) - often used either as a template for pareidolia, or as "evidence of fakery".

Astrophotography
Astrophotography causes more problems for the irrational than any other type of photography
 * 1) Polar alignment compensates for the roundness of the earth and varies with latitude.
 * 2) Deep sky objects raise the question of why the hell god would create astonishingly beautiful sights that can only be seen with a long exposure taking through a terrifically high magnification lens. The distance of these objects also raises problems for YECs (starlight problem), and the habit of many astronomical objects of exploding and destroying entire star systems seems to annoy creationists in much the same way that one might be annoyed to learn that your landlord's other properties often have a tendency to explode and take the whole town with them.
 * 3) Mosaic (stitched) images are a goldmine of accusations that "all space images are faked" - usually because the space denier doesn't realise that space is big and you need to zoom in to take pictures of it... which reduces your field of view, so if you want a detailed photo of something big you simply must make a mosaic of images and overlap them. This is a pretty dumb accusation for a culture that has been habitually carrying mobile phone cameras that feature the ability to photo-stitch (panorama mode) for a good fifteen years... it really isn't a hard concept to grasp!

Optical aberration

 * 1) chromatic aberration (common with cranks claiming things are holograms, particularly when pointing cheap cameras at the moon).
 * 2) defocus aberration (again, common with cranks who take an out of focus shot of an aircraft, or again, the moon, and claim it's a hologram because the edges are overblown or contrast is reduced.
 * 3) Perspective distortion (common with flat earthers who get confused about the apparent variance in the size of a continent caused by using a wide-angle lens up close vs a narrow-angle (zoom) lens from far away. Put simply, if you use a wide-angle lens up close, you will capture a lot of the background, while if you use a narrow-angle lens from a distance (zooming in), you capture relatively little of the background because your field of view is decreased, and you have simply moved further back to allow you to fit your subject in. Can be easily demonstrated with a globe and a zoomable camera...)

Refraction
Flat earthers seem to struggle with this one, usually relating to measuring the curvature of the earth

Perspective

 * No, the shafts-of-light seen through clouds don't prove that the sun is 7 miles up.
 * No, clouds don't appear to move very quickly through space because they are really big, and really far away.
 * Make use of the ant analogy (camera up close with a very narrow field of view - the ant moves across the field quickly - then move the camera far away and use a wide field of view - ant seems to take forever to move across the field.)

Umbra, Penumbra, and Antumbra

 * 1) Antumbra is not in fact an umbrella for ants.
 * 2) Flat earthers and space deniers seem to struggle with this every time there is an eclipse (usually to claim that the shadow is too big/small proving that the moon/earth/sun is actually closer/smaller NOTE[the moon/sun is never further/bigger: because these sorts of cranks are obsessed with making the world seem small and significant to them. A bigger sun that's further away just makes them feel small and god wouldn't want to make humanity feel small would he?]

Parallax

 * 1) Notes on terrestrial parallax
 * Usually abused by people claiming planes don't fly as far/fast as they actually are, and thus the earth is smaller than claimed NOTE[again, it's never bigger than claimed, always smaller]
 * Sometimes abused by space deniers who use cloud motion to "prove" the moon or sun is a few miles up.
 * 1) Notes on stellar parallax
 * Causes problems for geocentrists, and space deniers claiming that the stars are closer than they appear, and/or fixed (optionally to a dome).
 * Causes problems because it shows that the heavens aren't points on a dome but exist in a three-dimensional universe, and that a lot of them are ridiculously far away.
 * Often claimed to simply not exist (measurements of it happening notwithstanding, because who needs evidence?)

DRAFTING NOTES
Of note are: Exposure - particularly common with astrocranks: everybody from space deniers, flat earthers, geocentricists, and moonlanding deniers, but it also crops up amongst all sorts of other crank fields. The most common issue is to do with light and dark objects existing in the same frame... and only the light objects being visible ("If that picture was taken on the moon how come there are no stars, huh!"). Likewise, weird streaks on images (dust), rods (insects) and orbs (diffuse reflections) are popular artifacts relating to exposure. Similarly, a lot of cranks seem to take issue with shadows being really dark in a well lit scene (poor dynamic range). Finally

Astrophotography - relatedly, a lot of space deniers, geocentrists and flattards seem to struggle with understanding startrails caused by the earths rotation (and how simply rotating the camera at 0.3°/minute around the polar axis (that is, pointing north and elevated by your latitude so that you are aligned with the axis of earths rotation) perfectly corrects for this, providing a convenient proof of the rounditude of the earth while they're at it (since on a flat earth, the polar axis would always be perpendicular to the plane of the earth, you would always rotate it around the horizon... astronomers figured out in the 18th century that the polar axis isn't perfectly aligned to the ground wherever you are...). Deep sky objects are also a problem for creationists - as they seem to struggle to comprehend why god would create a whole observable universe that you can't actually observe without the ability to take a long exposure... oftentimes with a ridiculously long focal length lens, and that's before we get to how astronomically far away these objects are, and why some of them have a habit of randomly exploding and wiping out entire star systems only to replace them with bedlam. I have heard at least one street-preacher, when asked about this, claim that the devil was doing it to mock god by destroying his creation/mislead humanity. Satan has a star-crusher, who knew!? I'll need to find citation for this if I'm using it as an example - if a street preacher said it (when asked) it might not be a common opinion...

Mosaics - again, popular with various space cranks - who don't seem to realise that if you want a large image with detail, you can't capture the whole image at once (not without amazing optics and a very good big sensor) - so you zoom in to capture maximum detail in a small area... but if you want a panoramic image you have to stitch a bunch of very small images together to make a very big image... with the advent of panorama/photostitch modes in practically every smartphone (and how incredibly easy these modes are to operate), it is a true testament to willful ignorance that people can't appreciate mosaic images taken by space probes.

Optics in general - popular with cranks claiming that anything and everything is a hologram - from aircraft, the stars to the moon. Almost always the result of things being out of focus and thus the edges appear to be expanded. This ties in with exposure due to light diffracting around objects making them appear smaller, particularly during long exposures. Likewise, a lot of cranks (usually but not always related to eclipses) seem to take issue with the possibility that shadows don't simply start and stop, but actually have a penumbra, and umbra, and an antumbra depending on where you are relative to the light sources and any obstructions.

Depth-of-Field vs field-of-view - again, popular with flattards who claim that the apparent size of continents when seen from space changes (this is due to background compression: if you use a wide-angle lens up close, you will capture a lot of the background, while if you use a narrow-angle lens from a distance (zooming in), you capture relatively little of the background because your field of view is decreased, and you have simply moved further back to allow you to fit your subject in. Can be easily demonstrated with a globe and a zoom-capable camera)

There are plenty more examples (parallax (both terrestrial and stellar), sensor noise, image compression artifacts, colour correction, etc).