Canon Speedlite 580EX Hot-shoe clip-on flash

Author's product rating:   

Advantages:	Very powerful and flexible advanced users flash gun, easy full - auto use .
Disadvantages:	Expensive, complicated parameters setting, can cause subjects to blink .

Recommend to potential buyers:

yes

Full review

Overview
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Canon's premium EOS series dedicated flash gun with a guide number of 58 for powerful lighting and remote control of up to two sets of other 580EX or 430EX guns.

Features
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As the most powerful flash gun I have ever owned, the 580EX is a formidable beast. It's a quite large and heavy unit by consumer standards but fairly small and light by professional standards. It takes 4 AA cells and rechargables are definitely best, reducing the cycle time to full charge by quite a way to about 6 seconds. There's a socket for an external rechargable power pack which extends the number of flashes considerably and reduces the cycle time even further for rapid fire studio work.

The head tilts up and round to cover a full 180 degree hemisphere so even when cliped on the EOS body it can be directed almost anywhere for bounce flash. The head has a motorised zoom to change the angle of coverage to suit lenses from 24mm to 105mm in steps. It also has a manual flip down diffuser to cater for 14mm lenses. In the forward position, the head also tilts down one click for macro close-up shots. Although I've never used it, there's a little white flag that can also be pulled out of the top (with the diffuser) to curtail / direct light.

A red LED AF illuminator makes a pattern of red stripes that help the EOS bodies to focus in the dark. This is particularly useful for the pro bodies like the 5D that do not have an AF illuminator built in. The 20/30/40D series bodies have popup flashes that double as AF illuminators. The AF illuminator can be turned off (either from the body menu or as a custom setting on the gun).

E-TTL II flash metering means that the gun fires pre-flashes and the camera body can then compute the total exposure before firing the full burst a fraction of a second later. The pre-flash is also used as the remote control communication method with up to two sets of slave guns on three channels (the 580EX will be A and multiple other guns can "listen" to channels B and C).

A large and clear LCD display gives information about the gun mode, status and settings.

The newer dedicated control E-TTL II system is supposed to compensate for flash colour by sending information to the body to compensate the white balance and also react to information from the body if it advertises that it is a crop sensor body rather than a full frame body.

Using the 580EX
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The 580EX is not for the beginner or the faint hearted! There are a raft of functions and a large number of settings that can be changed and most require reference to a manual to decode the meaning. The LCD only allows you to numerically set functions (such as "C.Fn 01 = 1 or 0" for custom function 01 = on or off). You have to refer to the manual to find out what each function does. Basic settings are easy enough though and you can just clip it on a camera and turn it on and it will work in full E-TTL II auto mode. Depending on the type of body used, you might find that most flash functions can be commanded from the body, such as Flash Exposure Compensation, Flash Exposure Lock (similar to normal AE Lock) and 1st/2nd Curtain flash. For bodies that don't have such commands, the 580EX can do all this via the control dial and LCD.

The FEL feature in particular can be useful as it can be triggered by the AEL button on the body so you point at the thing you want to flash spot meter, press the AEL button and the flash pre-fires to measure the reflected light and then locks the exposure. You then recompose the shot and fire the shutter for the pre-metered exposure... very handy.

As well as varying the auto-exposure settings for flash, you can also select flash bracketing where three exposures can be taken and each will be at standard, + power and - power, similar to non-flash exposure bracketing.

You can set fully manual flash power on the 580EX in steps from 1/128th power to full power for completely manual setups and you can remote command the slave guns to fire in ratios of power to each other and the main gun to control side and back-fill lighting.

Performance
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In use, I've found the coverage of the flash to be a bit narrower than the lens sometimes - usually at close range and at wide angles below about 35mm. This doesn't often cause me a worry as I rarely use direct flash, preferring to bounce off walls or ceilings. This may also just be a feature that is exaggerated by the natural tendency for corner shading when using wide lenses on a full frame camera like the 5D. The E-TTL II system works very well and despite the loss of light when bouncing, the pre-flash metering usually does a sterling job of measuring the right amount of flash for any scene. The AF illuminator works really well, allowing the 5D to focus in pretty much total darkness, provided the subject is within about 5m and is reflective enough to show up the red stripes.

One problem I have found though with the metering system is that some people and most animals can see the pre-flash and so you often get pictures where they are half blinking, in unconscious response to the pre-flash.

Without the common red-eye reduction pre-flash burst of most cheap cameras, the 580EX won't reduce red-eye and may even temporarily blind your subject with it's power but then you should be using this gun on a off-shoe cord to avoid red-eye anyway. Similarly, if you are using bounce flash they won't have red-eye and won't be blinded and won't look like rabbits caught in headlights either! So the lack of a red-eye function is not really an issue.

Because the flash is measured exactly, recycle times can be very fast if only partial power was needed. The gun can also fire even if it's not fully recharged in cases where you are rattling off shots and want to get some light - even if it's not enough.

I should mention that a friend used a 580EX for an animation shoot outdoors in the dark and the continuous cycling at full power and full speed for hundreds of frames (from internal batteries - so not as rapid as it can go with the external pack) caused the thing to overheat and die... We're not sure if it was an unlucky instance with that gun or a risk you'd run if you did it with any example of the model... In my more normal use, I've never had a problem and neither has he (with the replacement gun he was sent under warranty).

Value For Money
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It has to be said that £320 is a lot of money for a flash gun. If you shop around you can pick it up for about £280, especially as it's been superceded by the 580EX II. Is it worth the extra money compared to a Metz or Jessops £120 compatible? Probably not in most cases unless you are going to use it a lot and really want to explore advanced manual setups. I don't know how well the cheaper independents do on the emulation of the dedicated exposure control but I do know that the 580EX is very good at auto exposure.

It's debatable whether the flash white balance communication is worth the money... If you bounce off some white-ish wall or ceiling you'll end up correcting the whites in software anyway.

Compared to other independent guns I've owned in the past, the build quality of the Canon guns are very good, plastic but much better than the sometimes cheap mouldings of the others. The 580EX II improves on this further by including a metal hot shoe foot and weather sealing for use in the rain (when used with a suitably weather-proofed body).

Conclusion
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Great performance at a premium price - good if you've got deep pockets and want to use the built-in wireless slave features with other Canon guns (basically other 580EXs or 430EXs). If you don't need the extra power and quite so many bells and whistles, then the 430EX is a smaller and more affordable option that retains the useful dedicated E-TTL II metering capabilities.