Are there any benifits to using a speedlite vs. a third party flash? I have been thinking of getting a flash and wanted to know what the pros and cons to them are. Any help would be greatly appreciated. Thanks.
Speedlight is a generic term generally applied to portable shoe-mounted flashes. Nikon, for example uses the same term but calls them "Speedlight" vs. Canon's "Speedlite" (note the different spelling).
So I'm assuming what you're really asking is: Is there a benefit to using Canon brand speedlites?
The answer is that a speedlite often does far much than just provide a brief burst of light.
Canon's E-TTL speedlites often do many of the following:
E-TTL shooting: the flash fires a pre-flash at a reduced (usually 1/32nd power) level so the camera can evaluate the difference (using "evaluative metering") of a non-illuminated vs. illuminated at 1/32nd power image. This allows the camera to determine if there are reflections or light sources within the frame that would normally throw the accuracy of the flash metering and provide for more accurate lighting. The camera then sets the actual flash power it wants to use and fires again -- this time with camera shutter open -- to take the photo. These two flashes happen so fast that unless you watch _very_ closesly, you'd swear it only flashes once.
High-speed sync: The camera has a mechanical focal plane shutter with two "curtains". One slides open... the other curtain eventually "follows" it to slide shut. If the camera only had one curtain then the pixels on the edge of the sensor where the shutter first starts to open will get more light than the pixels on the other edge. This dual-curtain design allows for even lighting at any shutter speed. But this creates a problem... the mechanical shutter can only move so fast. A camera that can shoot at 1/4000ths sec can't actually move the shutter that fast. The "flash sync speed" (usually 1/200th or 1/250th in most cameras) is the fast speed that the shutter can physically COMPLETELY open and then completely close. To create shorter exposures (say 1/500th) the 2nd curtain actually starts to close when the 1st curtain is only half-opened. This creates a slot where light is exposed. If the flash fires in this situation then only the area exposed between the two curtains gets the light and everything else is dark. To combat this, Canon's advanced flashes support "high speed sync". This causes the flash to fire pulses of light carefully synchronized to the shutter speed so that the entire frame receives an even amount of light from the flash.
2nd curtain mode: The camera normally fires the flash as soon as the shutter has completely opened. In 2nd curtain mode the camera delays the flash and fires it *just* before the 2nd curtain closes. If there is to be motion blur in the exposure, then this creates a better looking effect (the blur appears to be "behind" the subject movement rather than in front of it.) You can search for images that show the difference between 1st curtain and 2nd curtain flash to get a better idea of why this is important. It's one good way to use a flash to show off "motion".
Multi-strobic mode: This mode allows you to program the flash to fire a specific number of times with a specific interval between each pulse. In a long exposure, it means you catch a subject at multiple positions within the same frame -- a nice effect and another great way for showing "motion" using flash.
Focus assist beam: The flash profects a pattern using a red beam (this is red "visible" light though many confuse it for being infra-red because it's hiding behid a red tinted plastic lens) which allows the camera to easily lock on and focus subjects even in completely darkness. This is great for low-light events.
Multiple flash "commander" or "master" mode: This allows the flash to act as a trigger to control the firing of other remote flashes (and even remote cameras).
Multiple flash "remote" or "slave" mode: This allows the flash to be triggered by a commander in perfect syncrhonization with other flashes.
Weather sealing: Canon's higher end flashes have sealed hot-shoes. If the flash is used with a sealed body and sealed lenses then it's safe to use the flash in situations where it may get wet (or dusty) without fear of damage (by which Canon means "wet" by being splashed or rained on... not wet by being submerged. Weather seals are not weather-proof.)
Canon brand flashes tend to be more accurate and consistent in terms of firing the correct amount of power.
Canon's newest flashes (currently the 600EX-RT units) are also radio equipped so they don't require line-of-sight to control or be controlled for remote shooting.
There are other features as well (build quality of the flash, ability to swivel (pan/tilt) the head, does it have an adjustable (or automatically adjustable) beam to match the zoom on the camera lens. Does it have a built-in bounce-card / catch-light card? Can it operate off external batteries? Etc.
When you look at 3rd party flashes (often much cheaper) and go through the list of features agains the Canon brand flash you think they compete with, you'll find the list of features on the 3rd party flash will not be as complete as the list of features on the Canon brand flash.
Every time I have done this analysis, I find that by the time I can find a 3rd party that comes close, the price tag is no longer inexpensive.
It's fair to say that not everyone needs all these features... and for some people an inexpensive flash with minimal features is fine. Usually however, it is still at least very important the flash provide the same amount of power based on the power level set (some flashes are randomly a little more or less powerful on each burst even when the power level is manually set to be the same. That'll drive a pro absolutely nuts.)
That said, I did all my studio and wedding work using nothing but comletely manual flashes. There's a bit of a learning process to it but like anything... you get out of it what you're willing to put into learning it.
Today I mostly just use the new 600EX-RT flashes and I sure do like them -- even though I completely understand how to shoot on the fly using only manual flashes. I love the reliability and simplicity of the new radio technology.
BTW, I left out the part about the "guide number" of the flash. That's an indicator of how far away the flash can properly illuminate a subject assuming the camera is set to a specific baseline ISO and f-stop (which happens to be ISO 100 and f/1.0).
Canon's model numbers are actually an indicator of the "guide number" as measured in meters. Just omit the trailing "0" from the model. So a 270EX II has a guide number of 27 meters. A 430EX II has a guide number of 43 meters, etc. This is true of Canon but usually NOT true of most 3rd parties. For those you would have to do some research to look up the guide numbers.
A 430EX II makes a great flash for most Rebel bodies... having enough power to cover most situations with ease and it's a very reliable work-horse flash. It can operate as a "slave" but cannot operate as a "master" in a multi-light setup. But it does support 2nd curtain mode and high-speed sync modes. I don't consider it to be a problem that it can only be a "slave" because by the time you're ready to buy flash #2 (if you ever choose to get more flashes) then you just make sure flash #2 *can* be a master and then use the 430 as the slave (which is exactly what I did.)
Incident light meters that support flash metering will give you a very accurate reading, but you can usually see it in the images as you know when you have a series of images that were taken with the same flash, same power setting, and same subject distance... yet have are not all exposed similarly as you would expect.
A fairly basic meter that can do flash metering such as a Sekonic L-308s will give you a reading. Higher end meters even do flash contribution percentages (ideal for outdoor fill flash).
***[BTW, I left out the part about the "guide number" of the flash. That's an indicator of how far away the flash can properly illuminate a subject assuming the camera is set to a specific baseline ISO and f-stop (which happens to be ISO 100 and f/1.0).]
Note what TCampbell is saying carefully though. You are not going to find an f/1.0 lens in the real world, so you need to know you can't assume you will be getting 60 meters range on a 600 RT flash under most normal conditions.
The f/1.0 baseline works well because you can arrive at the effective distance by dividing the guide number by the f-stop you actually plan to use. E.g. if you're using f/5.6 then you divide 60 ÷ 5.6 (which gets you about 10.7 meters which is about 35 feet).
Each time you double the ISO you get to multiple that distance by 1.4. (all the math is based on powers of the square root of 2). So at ISO 200 the distance goes from 35 feet to about 49 feet. It's sometimes easier to remember that if you bump the ISO up by 2 stops (instead of just 1 stop) then you get to double the distance. So at ISO 400 (instead of ISO 100) the 35' becomes 70'.
That's without using any modifiers on the flash. Many modifers are going to eat a little of your light (a diffuser might eat a full stop) and bouncing the flash (e.g. off a white ceiling) is not only going to increase the distance that the light has to travel, it's not going to reflect all the light -- so it will eat a bit more light.
This is why the flash sounds really powerful.... but once you start adding light modifers and/or bouncing the flash, it turns out that power really comes in handy.
So another words, generic brands are good up to a certain point, but in order to get all the bells and whistles including the correct metering and power I would need to get Canons brand.
Yes -- the point of my post wasn't to say you have to buy the Canon brand flash... but really to point out that flashes have far more features than just providing a momentary burst of light. The inexpensive flashes will provide basic flash functionality.
The least expensive 3rd party units are entirely manual. There's a step up (still inexpensive) which provide basic E-TTL functionality, but not the full functionality.
Even if you have an E-TTL speedlite, it would still be a good idea to learn how to do flash photography entirely in manual operation because this helps you learn more about how flash photography works. It's the same reason we encourage people to learn how to use the camera entirely on manual because you learn a lot more about exposure that way and you learn how changing a particular element of the exposure affects the outcome (and then knowing this, you'll be much better at knowing when to choose the semi-auto modes, which mode to use, and which settings you should control and which settings you should let the camera control.)