1719: Superzoom

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*click* Let him know he's got a stain on his shirt, though.
Title text: *click* Let him know he's got a stain on his shirt, though.

[edit] Explanation

In this comic, Cueball is showing off his new superzoom camera to White Hat. These are cameras with large zoom lenses, often up to 25× or higher magnification. He is very excited and starts by exclaiming how they can take detailed photos of the craters on the Moon, and (on better models) relatively large photos of Jupiter even with a resolution so individual clouds can be seen. (See examples of zoom on these objects here and here without cloud resolution though, but with Jupiter's four large moons and Saturn's rings.)

He then spots a bird (which is just a speck in the sky) and uses the superzoom for birdwatching, which is a popular use for these cameras. He can see that it's a peregrine falcon and that it has been banded (ringed) and he can even read the number on the band (later it seems he has more trouble locating birds with his camera in 1826: Birdwatching). He then spots an airplane and having taken a picture of it, he can tell that it is a 787 Dreamliner from Japan Airlines, and he can even make out the registration number. All this is possible, with a Nikon Coolpix P900, which may not be much larger than the one Cueball stands with here, with an extremely long lens, and at the time of this comics release that type of camera could be bought at Amazon for less than $600. If that is within the limit Cueball gives of a few hundred dollars can be debated... A SX-60, refurbished with optical zoom currently sells for $379. Its predecessor, the SX-50 sold, refurbished, for less than $200 until going out of stock.

Note that before each comment he has taken a picture, presumably zooming further in after each photo of each new object, zooming out again before beginning with the next object.

Finally, White Hat exclaims that he is sold and states that he also want a superzoom camera like Cueball's. Cueball then points the camera down the street takes a picture and tells White Hat that the shop on Union Road has these camera in stock, indicating that he can see this inside the store (or in their window). He then takes another image and is able to make out not only the worker Kevin inside, he also recognizes him and (as mentioned in the title text after taking yet a further zoomed in picture) notice a stain on Kevin's shirt. He seems to like Kevin and asks White Hat to tell Kevin about the stain when he goes there to buy a superzoom camera. (This was the first time the name Kevin was used in xkcd for a fictive person, see more in this trivia).

Even with the ability of these cameras, it would be difficult for Cueball to be able to make out a specific worker inside the store, but if he is standing near a window it is not impossible, and if he has a stain on his shirt, it is in the same league as spotting a band on a bird in the air. Of course he has to be in a spot where he can see straight to the front of the shop.

The last panel and title text is also a remark on how such cameras can be used to spy on people for quite a far distance, which has often been (mis)used by paparazzi photographers taking pictures of famous people (often while almost naked or in bikini or other bathing clothes). Now everyman gets this disconcerting possibility to spy on their neighbors and others for just a few hundred dollars.

There are lenses that can do what Cueball describes about Jupiter's clouds in the comic (e.g., the Canon 5200mm), but so far not such a small consumer camera as shown in the illustration.

A couple of other factors that many people may not realize until after they've bought a consumer-level superzoom camera is that a) taking a hand-held picture at maximum zoom is typically rather blurry because the lens is magnifying all vibration and it's impossible to hold the camera steady enough (so a camera tripod would be needed), and b) that the lens' aperture at maximum zoom is typically much smaller than at normal focal lengths, with the result that the shutter time must be several times longer to get proper exposure, compounding the vibration / blurry problem. Modern superzoom cameras do have "image stabilization", which can mitigate blurriness due to vibration, but extreme telephoto photography is still more challenging than implied in the comic.

Also having zoomed so much it is very hard to actually locate a moving plane or bird in the sky while looking at the image shown on the camera. And as shown in the comic the lens is zoomed very much in. Of course this could be done by Cueball after having found the flying object with much less zoom. But still if he loses sight of the bird while fully zoomed in it will be almost impossible to find it again without zooming back out.

White Hat and Cueball have discussed photography before in 1314: Photos.

[edit] Transcript

[White Hat and Cueball are walking right. Cueball is looking down at a camera with a long lens he is holding in both hands.]
Cueball: I love these superzoom cameras. For a few hundred dollars you can take pictures of Moon craters and Jupiter's clouds.
[They stop, White Hat looks up in the air while Cueball does the same but through the camera he is holding up to his eye while taking pictures. The camera lens is further zoomed out and is clicking.]
Cueball: And birds! See that speck up there?
Cueball: Peregrine falcon!
Cueball: It's banded, too. Want the number?
[White Hat looks even further up as Cueball turns left and point the even further zoomed camera almost straight up while taking photos.]
Cueball: And see that plane?
Cueball: 787 Dreamliner
Cueball: Japan Airlines.
Cueball: Registration is—
[White Hat looks back down on Cueball who has turned to the right holding the fully out-zoomed camera level to the right along the ground.]
White Hat: OK, I'm sold—I want one.
Cueball: They're in stock at the place on Union Road.
Cueball: Hey, Kevin's working today! He's great.

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Camera guy is an asshole. (talk) (please sign your comments with ~~~~)

Didn't realise donkeys could fit in a guy!
Anyhow, does anyone know if those cameras are really that good? (talk) (please sign your comments with ~~~~)

Alternatively, its possible he's borrowing this camera from beret guy. Too bad he didn't check to see if it dispenses soup; now we'll never know. 15:08, 12 August 2016 (UTC)

I don't think the comic mentioned anything about the price of the camera. 16:12, 12 August 2016 (UTC)

Yes, he does; see the first panel. But I had to look twice after reading your comment.  :) 16:59, 12 August 2016 (UTC)

I think this comic might be inspired by this video I recently saw [1] --Eluvatar (talk) 17:48, 12 August 2016 (UTC)

Here's a video of the Nikon P900 https://www.youtube.com/watch?v=p-0X3xJf-kg which has 166x optical zoom (talk) (please sign your comments with ~~~~)

Thins this last video is more relevant than the one above. Have used this in the explanation. --Kynde (talk) 12:30, 13 August 2016 (UTC)

This feels like something Buttercup Festival would think up of. 19:56, 12 August 2016 (UTC)

I understand cruising altitudes vary, but I've been able to see airplane reg numbers using a 6MP APS-C dslr at 200mm and post-shot image review zoom. Has anyone done resolution math to fact check the assertion? 23:10, 12 August 2016 (UTC)

Editing this comment to add: And the title text - note the stain shirt is after the click comment. Really sounds like zooming into the image - which at a high resolution, shows a lot. (talk) (please sign your comments with ~~~~)

Never mind the distance factor. I'd be astonished if he can make out who's working in the store if there are any walls in the way. 08:54, 13 August 2016 (UTC)Andrew Williams

Have you heard of windows? ;-p Who says he is that far away. To me it seems that such a small camera as shown here can do all he claims except take pictures of the clouds of Jupiter, see links in the explanation. Also there are no indication of how far away either bird, plane or Kevin is, so it is not possible to say they are too far away to see anything. And of course they have to be visible from Cueball's location, it's not an "x-ray" camera with superman vision! The number on the birds band is probably not readable from just one side of the ring/bird, as it goes around the ring... But to make out those numbers turned his way may be possible. However as he is looking up indicating the bird is flying it would be difficult to get a great picture (especially handheld). But if the falcon is soaring it can stay very still even in the air. So apart from the handheld part it seems very likely that this is possible, and that is a bit scary. Any time you are standing in a spot where someone can see you from afar, then they can tell if you have forgotten to zip up your fly from a couple of miles away! ;-) --Kynde (talk) 12:25, 13 August 2016 (UTC)

Super zoom doesn't mean super magnification; a zoom lens is a lens which allows the focal length to be varied. Some zoom lenses (e.g., Tamron's 150-600) do give high magnification, but others (e.g. Nikon's 10-24mm) do not magnify. "Super zoom" isn't even a word that has meaning, though I suppose something like a 8-300 could be called super zoom (if it could even be built) A telephoto lens magnifies; a super telephoto magnifies a lot. The opposite of a zoom lens is a Fixed focal length, aka Prime, lens. Long lenses (over 100mm) are telephoto. The 5400mm lens linked to in the explanation is a Prime lens (essentially a telescope with a camera mount; notice it's a reflector design, not a refractor like a zoom lens must be). As far as reading bird bands, I use a Tamron 150-600 at 600mm on my Canon 5D when recording bands during spring snow goose migration; works well for birds up to 150 yards away or so. Note that goose bands are much bigger than those used on Falcons. That lens is properly called a telephoto zoom lens. 04:56, 14 August 2016 (UTC)

Superzoom (1 word) is a term for a fixed-lens camera with excess of "15x" optical zoom. Source: 7 years of reading Popular Photography magazine covers. (talk) (please sign your comments with ~~~~)
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