Etymology question: "Hotshoe"

<p>I recently inherited a Canon DSLR with a Speedlite flash, and was surprised to find the flash ran out of batteries before the camera did. My assumption, clearly mistaken as it has proven to be, was that the flash draws power from the hotshoe. I figured the 4 AA batteries inside the flash were for control, memory or something...<br>

Feel free to laugh, but to a novice photographer, or anyone familiar with electricians' use of the term 'hot' to mean 'powered' the term hotshoe implies the conveyance of some sort of power. <br>

Which brings us to my question: If it doesn't actually power a flash, why did they (who?) call it a hotshoe in the first place?<br>

Thanks. </p>

<p>It's a hot shoe because it communicates electronically with the flash, as opposed to the older "accessory shoe" (now often referred to as a cold shoe) that merely provides a place to attach the flash.</p>

<p>Originally, the shoe just held the flash in place, and a separate cord was needed to have the camera trigger the flash when the shutter was released. The hot shoe provides the sync signal without needing a separate cord. These days, with the camera and the flash both being computerized, additional information is exchanged as well for TTL flash control.</p>

<p>"Cold Shoe" (or flash shoe) referred to on-camera flash mounts when the flash still synchronized with the camera via a separate PC cord. Hot Shoe refers to the camera connection that supports synchronization and transfer of exposure info. between the camera and flash via this mounting point.</p>

<p>History started with a shoe for mounting only, with no connectors. What we today call a cold shoe. A hot shoe has electrical connectors, at least one center pin and a ground. When you connect those two together the flash fires. Your Canon also have a few other connectors so the flash and the camera can communicate. These connectors are way to tiny to power a flash.</p>

 

<p>The term "hotshoe" was coined to differentiate that type of accessory from the earlier and more common "cold shoe" slots that only served to hold an accessory - typically a flash but sometimes a light meter or rangefinder - without either the camera or accessory controlling or communicating with the other.</p>

<p>For example, my older cameras such as an Agfa folding camera and Yashica TLR have cold shoes that can hold a flash, light meter, rangefinder or other device. In order to activate the attached flash, a cord must be connected between the flash unit and a socket on the camera through which a mechanical trigger, timed with the shutter, activates the flash. Those flash units were typically powered by internal batteries or external battery packs, not by the camera (since many of those older meterless cameras had no batteries at all).</p>

<p>The first hotshoe devices were simple single contacts that allowed the camera to trigger the flash without needing an accessory cable. As flash units became more sophisticated additional contacts were provided to: trigger a flash-ready lamp in the viewfinder; set the camera to maximum synchronization speed; and eventually for sophisticated TTL flash.</p>

<p>Offhand I can think of only one camera and flash unit I've owned for which power to the flash was supplied by the camera battery - that was an accessory flash unit for an Olympus XA-4 compact 35mm camera. It's been so long since I owned that outfit I can't recall whether the accessory flash unit also had an internal battery that eventually needed to be replaced.</p>

<p>Otherwise, with most such flash units the batteries in the flash provide the power. Some hotshoe flash units can also be powered by external battery packs, either from the manufacturer or from a third party company like Quantum.</p>

<p>If it's just the etymology you're interested to know, it started to be called a hotshoe in the late 60's or early 70's when they put the electrical connector in the accessory shoe itself to mate with a corresponding one on the foot of the flash, rather than having to connect the flash to a port via a cord. It wasn't electronic and it communicated no exposure information whatsoever. All it did was to close an electrical circuit at the appropriate time when the shutter went off. The camera didn't even need to have a battery, because the power was and still is in the flash itself.</p>

 

<p>While I don't know who first coined the term "hot shoe", my 1948 Bell & Howell Foton has a flash hot shoe. It was intended for their own flash units. No PC or other synchronizing terminal was provided.</p>

<p>http://en.wikipedia.org/wiki/Hot_shoe</p>

<p>Good Question . . .</p>