1855: Telephoto

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Telephoto
I was banned from the airliners.net photography forum by concerned moderators after the end of my lens started brushing against planes as they flew by.
Title text: I was banned from the airliners.net photography forum by concerned moderators after the end of my lens started brushing against planes as they flew by.

Explanation[edit]

Telephoto lenses are special lenses for cameras that are physically shorter than their focal length. Using a long-focus lens allows the photographer to magnify a photographic image of an object rather than being physically close to the object. Alternatively one could add "converters" and "extenders" to an existing lens to get a greater focal length for the cost of reduced brightness. The joke is that Cueball did not want to spend the money on buying a new telephoto lens or real converters, and instead achieved the same effect by moving his cheap camera (a standard webcam, in this case) close enough to the subject to obviate the need for magnification.

There are many problems with this. First, the end result is completely impractical to carry around; as shown in the comic, Cueball has to set up two tripods just to support the weight of his hulking behemoth of a camera. Second, if you're an animal photographer like Cueball, you need to be able to see the animal as close up as possible in order to get a good picture; a lens with lots of magnification power accomplishes just that without alerting the animal to the photographer's presence, but Cueball's camera would surely scare off any birds he tried to photograph (except in fanciful proof-of-concept diagrams like this comic).

Perhaps most damning of all, though, is the fact that Cueball's idea involves installing a webcam at the far end to be able to photograph anything. Webcams are not designed to capture high-resolution images, so the resulting image will be of considerably lower quality compared to professional photographers' works, although it could be better than a standard camera setup taking account of the huge achievable zoom levels. But more importantly, the presence of the webcam renders the functionality of the extenders (and the base camera itself!) completely redundant, cementing this idea as a total waste of money and effort. The same could be achieved by mounting the webcam on a long stick; an extraordinary long selfie stick will achieve nearly the same effect, for considerably less cost and set-up than Cueball's behemoth.

The title text continues this by saying he was banned from the Airliners.net photography forum because his new modified lens was so long that it started brushing against planes as they flew by. If Cueball's gargantuan lens is being set up on or near runways or is so long that it potentially damages planes in-flight, then being banned from an online forum should be the least of his worries.[citation needed] In-flight damage dealt to planes can cause severe consequences, e.g. causing them to crash. This would possibly put him on the no-fly watchlist, as well as being charged with unintentional damage.

Transcript[edit]

[Cueball stands behind a huge telephoto lens which rests on two tripods, one at the left in front of Cueball, and an other larger one in the middle. The lens is more than five times longer than Cueball is high. In front of the lens is a tree with a bird on top close to the lens. The bird is labeled "Subject". Inside the telephoto lens at the location of the objective lens a small device is shown and labeled "Webcam". From that device a small cable runs through the entire telephoto lens to the eyepiece, where an other device labeled "Camera" is shown.]
[Caption below the panel:]
Telephoto tip: If you add enough converters and extenders, you don't actually need a fancy lens.


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Discussion

Notice the "webcam" placed on the front element, and the cable running through the extenders and converters back to the camera body? The extenders and converters are only being used for mechanical support, to place the webcam near the bird, and not optically. 162.158.79.125 15:16, 26 June 2017 (UTC)
I understood it to be that the webcam was mounted on the side of the extender, allowing for a live stream in addition to the up close picture being taken. Raj-a-Kiit (talk) 16:25, 26 June 2017 (UTC)

That's how I took it, but the webcam and wires are drawn in a lighter line, possibly insinuating that the webcam and wires are inside the extenders and converters. OldCorps (talk) 16:53, 26 June 2017 (UTC)

It depends on how tall Randall actually is, but using an average of 1.7 m for humans, that camera is about 32 feet, 4 inches long (it's about 5.8 times the length of Cueball). OldCorps (talk) 17:04, 26 June 2017 (UTC)

Your comment makes me cringe. Apparently you measure people in metric but camera lengths (not focal length!) in imperial. So here you have it: 9,85m camera length! 141.101.76.226 20:11, 26 June 2017 (UTC)
Fair point, I'll simplify the equation. Cueball is 0.00845063 furlongs tall, the camera is 0.048984751 furlongs long. OldCorps (talk) 11:33, 27 June 2017 (UTC)
That's 1 and 5.8 Smoots respectively for those of you who don't live in an empire. --172.68.54.16 00:36, 3 July 2017 (UTC)

While I am at it I think using commas for decimal places is wrong. Needforsuv (talk) 13:27, 27 June 2017 (UTC)

Incorrect definition of telephoto

A telephoto lens is actually a lens of which the physical length is shorter than the nominal focal length. For instance, I have a 90mm Leica lens that is about 67mm long; this is accomplished through the optical design. A long-focus or long lens is a lens with a comparatively long focal length: on 35mm cameras, this is generally any lens 85mm and up. They are sometimes called portrait lenses. A zoom lens is one with a variable focal length, e.g., 70mm – 140mm. It is not necessarily a long lens.

The distinction is especially important to large format photographers, and the conflation of the terms is common among lay speakers.

Randall has conflated a telephoto lens with a long lens, as does the current explanation.

See http://camera-wiki.org/wiki/Telephoto#Long-focus_.28Telephoto.29 for on the topic. Seezee (talk) 18:21, 26 June 2017 (UTC)

It would be nice if you could enhance the explanation by this matter. I'm not an expert on photography but I believe Randall is just talking about a telephoto which is often also called telephoto lens. And his telephoto even doesn't need a single lens. Randall hasn't conflated anything, it's the explanation. I.e. instead of "100 foot lens" it should be "100 foot telephoto without lenses", and similar to other sentences.--Dgbrt (talk) 19:01, 26 June 2017 (UTC)

I am sure something like the contraption here will be a Long and Telephoto lens... like a telescope, yes you can get a lot of zoom under 200 mm lens length but then if you could do that they wouldn't have long telescopes.Needforsuv (talk) 13:27, 27 June 2017 (UTC)

Could this also be a reference to all those phone camera attachment advertised online. I don't know if there's any truth to their claims (somehow I doubt it), but if anyone knows better, please chime in. 162.158.6.94 (talk) (please sign your comments with ~~~~)

Were it not for the added weight of the tripod on the left, the right end would be on the ground. --Pascal (talk) 11:36, 27 June 2017 (UTC)

Ahh this comic is documenting how those iPhone ads that says "taken with an iPhone" was taken. Technically an iPhone was involved. Technically.162.158.88.140 17:03, 28 June 2017 (UTC)