If you're shooting from the stands, or even the dugout, it won't reach.
First of all, this is simply an erroneous statement. The 24-105mm numbers on the flash head refer to the beam width, not the range of the flash. Flash head zooming is done to allow the flash head to give full coverage over only the area seen by the sensor. Trust me, as one who uses a 580EX every Friday night covering HS football night game, the flash CAN and DOES reach well out past 50 yards. It's not terribly effective out that far, but if one adjusts their exposure quickly enough, and you don't mind getting a little occasional ghosting, it can be done.
From the excellent Web reference site, http://photonotes.org/articles/eos-flash
Canon’s mid to high-end external flash units contain small motors which move the flash bulb closer to or further away from the clear plastic screen at the front. This allows the flash to alter the coverage area of the light emitted from the unit - the closer the bulb is to the screen, the wider the coverage angle and vice versa. It also means that the flash’s light output can be concentrated for greater distances and used more efficiently. (ie: you aren’t wasting light by illuminating areas not covered by longer focal-length lenses)
Typically the zooming motor covers the range used by 24 to 80mm lenses or 24 to 105mm, and does so in several fixed steps matching popular prime lens focal lengths, such as 24-28-35-50-70-80mm. (continuous zooming control to arbitrary focal lengths is not supported) Remember that a flash unit’s upper zoom limit doesn’t prevent you from using the flash with longer lenses. All it means is that the zoom can’t concentrate its light beyond a certain point for more efficient coverage of a narrower area. At least, not without a flash extender accessory. The reverse is not true for the wider end, however. If you use, for example, a flash unit with 24mm coverage at the wide end with a 17mm lens you’ll get a kind of vignetting effect (darkening of the edges) since the flash will not be able to illuminate the entire coverage area of the wide angle lens.
Some zooming flashes have manual controls that allow you to override the automatic zoom setting by pressing a button. Others are only automatic - they zoom to a setting near to the current lens focal length when you press the shutter halfway. Canon flash units usually default to a 50mm zoom setting when in bounce mode and to 35mm when no EF-compatible lens is attached.
Most camera bodies with image areas less than that of 35mm film (APS cameras and most EOS digital cameras) cannot compensate for the cropping factor of their image areas. So you are, in effect, wasting light when taking a photo using such a camera body and a zooming flash unit, since areas outside the edges of the picture will be illuminated. This issue has been addressed with later model EOS camera and Speedlite flash units, as listed below. When these flash units are attached to a compatible camera a small nested rectangle icon will appear in the flash unit’s LCD. (note that it appears that a bug limits the utility of this feature when a 580EX is used on an EOS 20D - at 24mm or wider the flash may not zoom wide enough, which may result in some vignetting)
Remember that the flash head will zoom to the nearest zoom setting that is less or equal to that of the focal length of your attached lens. So if you have a 100mm lens attached, say, and the flash unit can zoom to either 80mm or 105mm, then it will automatically go to 80mm only. It will not narrow the light cone down any further by zooming to 105mm, as you would risk getting darkening around the edges of the picture if it did.
Wireless-capable units with zooming heads will zoom to 24mm when in wireless slave mode. Flash units with no manual zoom controls will always shoot at 24mm. However wireless slaves with manual zoom controls can be very useful in wireless mode since they let you set up your slave units around the scene, override the default zoom setting and adjust the coverage angles for each unit independently.
They aren’t so commonly used outside a wireless context but they allow you, for example, to create a sort of spotlight/vignetting effect by narrowing the flash coverage down to a tighter circle than that required by the focal length of the lens. (an intentional use of the problem outlined above) You can also use manual controls to adjust the zoom setting so that you can work with manual lenses which don’t transmit focal length information to the camera.
All Canon flash units which have names ending in Z, such as the 540EZ, contain zooming flash motors. However, mid and high-end E-TTL shoe-mount flash units (420EX, 430EX, 550EX and 550EX) also have zooming heads, so Z Speedlites aren’t the only ones with the feature.
Two EOS cameras, the Elan/100 and the A2/5, have three-position zoom motors built into their internal flash units. It’s this zoom capability that explains why the Elan/100’s built-in flash has a maximum guide number of 17 at 80mm. When the flash isn’t zoomed out it has a guide number of 12; typical for a camera’s built-in flash. Canon have not carried this feature through to any later bodies, however. Presumably the expense and bulk of the zooming mechanism were deemed to outweigh the benefit of improved guide numbers.
The primary disadvantages of a zooming flash unit are that the zoom motor makes a loud buzzing noise when adjusting coverage angles and that the flash head has to be larger to accommodate the motor.
Flash units with motorized zooming heads:
Speedlites 300EZ, 420EZ, 430EZ, 540EZ, 380EX, 420EX, 430EX, 550EX, 580EX, 580EX II.
John, a big part of where flash is and isn't allowed is safety, but another part is etiquette and tradition. The IHSA rules do not specify which sports allow flash - they only say it is allowed, dependent on the host school's approval.
Authorized news media representatives, who have identified themselves to the host school principal (or designee) may be permitted to use electronic lighting equipment throughout the course of a given activitfixed positions and/or 2) electronic attachments mounted to a camera.
One can make the safety argument about baseball, but this logic is contradicted by hockey, which is every bit as fast and has an every-bit-as-dangerous very hard thing being hit/shot/passed at high velocity, yet flash and strobes are used all the time when shooting hockey. However, it is universally accepted that artificial light isn't used in baseball, gymnastics, sometimes volleyball, frequently for cheer, often for indoor swimming, and a few other sports I'm forgetting, therefore I don't use it.
One of the bid reasons why I almost always use bounced flash is to minimize the perception of distraction. The other is that I like the look of bounced flash/strobes more, but that's subjective.
Having strobed or flashed well over a hundred events in the past few years (football, basketball, hockey, wrestling, soccer, lacrosse, judo), I can tell you I have had only had one complaint, and this was from the coach of a youth football team that was getting their butts kicked and the coach was using my flash as an excuse. I wanted to ask him why the flash wasn't bothering his opponent, but knew enough to cease and desist once his complaint had been registered.
I'm sorry, but it's comments like this that make me just shake my head. I do not know of a single pro shooter who would not choose to use artificial light when they need it and where it is appropriate and allowed. The results are not even close in so many ways.
