Friday, November 26, 2010

Flash: The Speedlite range

Over the years, there have been five different types of Speedlite, each operating in a slightly different way.

The Speedlite 200M (discontinued) does not support any type of TTL metering. Instead, it has its own built-in sensor to control the flash output. It was designed for use with the Canon EF-M camera. If used with an EOS camera, both shutter speed and aperture must be set manually.

The Speedlites 160E and 200E (both discontinued) are low power units designed as an alternative to built-in flash for those EOS models without built-in flash. They operate with TTL autoflash metering. E-series Speedlites are compatible with all EOS film cameras, but not with EOS digital cameras.

There is only one EG model − the Speedlite 480EG (discontinued). This is a hammerhead style unit that dates back to pre-EOS days. It is compatible with all EOS models, including digital, because in addition to TTL metering, it features an external sensor. This independent sensor means that flash metering can be done without using any of the flash sensors inside the EOS body.

EZ-series Speedlites operate with A-TTL metering on all EOS film cameras. In addition, they can be operated in TTL autoflash mode with the camera shutter speed and aperture set manually. This is useful when you need to shoot at a particular aperture − for increased depth of field, for example. They are not compatible with EOS digital cameras.

EX-series Speedlites operate with E-TTL metering on EOS Type A cameras. They switch to TTL metering when used with EOS Type B cameras. This means that EX-series Speedlites can be used with EOS digital and film cameras.

Only EX-series Speedlites are now current.

Speedlite 580EX

In August 2004 Canon introduced a new flash gun to its range, the Speedlite 580EX. It replaced the previous top-of-the-range Speedlite, the 550EX, but uses many of its features. The result is an easy-to-use, powerful, versatile flash unit for lighting on the go. In addition to making the unit even more feature-packed, Canon has also managed to make the entire unit smaller, lighter and far more aesthetically appealing.

Increased power
The most obvious change between the 550EX and the 580EX is hinted at in the name. The flash power has been increased from 55 at 105mm (ISO 100, metres) to 58 at 105mm (ISO 100, metres). This may not sound much, but extra flash power is always useful. And this increased flash power has another benefit, something which is very important in a flash gun − a faster recycle time. Because the flash is more powerful, you are rarely using it at full capacity, so it recycles to full charge more quickly. This means you don’t have to wait around for the flash to be ready to fire again in circumstances where speed and time are of the essence. Canon has also re-engineered the electronics so that even on a full power it will be ready to fire again more quickly than the 550EX. In fact, from a full power flash (with fresh batteries) the 580EX will recycle in six seconds or less, two seconds faster than the 550EX − and that’s with a more powerful flash.

The digital design
The biggest difference between the 580EX and the 550EX is that the new model has been specifically designed with digital cameras in mind. This means it has been endowed with two features not found on any previous Canon flash:

Sensor size detecting autozoom
Colour temperature transmission from flash to camera.
The Canon digital camera range incorporates models with three different sensor sizes: full frame (as found on the EOS-1Ds and 5D models), APS-H (EOS-1D models), and the most common size, APS-C (all EOS consumer DSLR cameras).

Previously, a flash gun would assume that the sensor was full frame, as most cameras were film and therefore used the standard 36mm x 24mm film size. Now, however, with the three different sensor sizes, there is more of a problem with flash coverage. To overcome this, Canon has developed a system to allow the camera to communicate its sensor size to the flash. This allows the flash head to zoom appropriately to suit the angle-of-view of the lens and sensor combination.

The biggest advantage of sensor-size detection is that it does not ‘waste’ power and light by spreading the flash over a wider area than is needed. You obtain more flashes per charge and a faster recycle time, as well as effectively extending the flash range.

The other digital-only feature is the colour temperature transmission from flash to camera. As the charge levels fluctuate in the flash power source, the colour temperature of the emitted flash varies. With this new feature, each time the flash fires, the colour temperature is passed to the camera so that an appropriate Kelvin value can be set to ensure the colours are more consistently correct between exposures. This will operate when the camera is set to either Auto White Balance (AWB) or the flash white balance setting.

The result is that you will obtain more accurate colours for each image, which will save time in post-processing on the computer.

Getting wide
In conjunction with the digital sensor autozoom, the built-in wide panel has been changed to give an even wider angle of coverage. You can use lenses as wide as 14mm with the Speedlite 580EX.

The top end of the flash zoom range remains the same, giving coverage for lenses with a focal length of 105mm. However, this is not the maximum focal length you can use with the Speedlite. It simply means that with longer lenses the flash will provide coverage greater than the field-of-view and some of the flash illumination will be wasted.

Bright eyes
Also new for a Speedlite is a catchlight reflector. This is found in the same slot as the wide-angle diffuser panel. It provides a much more flattering result when shooting portraits, allowing you to fire the majority of the flash up to the ceiling or off a wall, while bouncing enough light for some fill-in illumination on the face and a catchlight in the eyes to give them some sparkle. It will certainly be a welcome addition for anyone who shoots a lot of portraits, where direct, harsh light can be unflattering to your subject.

Fully focused
A big advantage of using a Speedlite on-camera is the help it can provide with focusing in low light, and the 580EX is no exception. Three ultra-bright LED lights are arranged on the flash to provide horizontal and vertical line patterns, resulting in an autofocus assist beam that is compatible with all EOS autofocus systems. This is an improvement over the 550EX, which could not provide complete autofocus coverage for all EOS cameras. As long as the subject is in range of the focus light beam, it should make difficulties with autofocusing in low light a thing of the past.

Bouncing around
In many situations where flash is used, direct light from a flash gun is often too harsh, giving unnatural and unflattering shadows. The 420EX and 550EX helped overcome this by adding a bounce flash capability, enabling angling of the flash head so that it can fire onto a reflective surface, such as a white wall or ceiling.

This has been further developed in the Speedlite 580EX, where a single button releases both the vertical and horizontal bounce flash movements. This makes the feature quicker and easier to use than before. The head is also now able to rotate 180° both left and right, compared to the 550EX, which could only be rotated 90° to the right. There is also an extra vertical click stop on the 580EX at 45°, giving more options when bouncing the flash from different surfaces.

In keeping with the improved ease of use and improved ergonomics of the new Speedlite, gone are the +/− push buttons on the rear of the unit. These have been replaced by a single control dial with a central button for scrolling between settings. This dial is used in the same way that the +/− buttons are used on the Speedlite 550EX. It makes choosing settings on the 580EX much quicker and easier.

Going manual
Despite the accuracy and simplicity of the E-TTL/E-TTL II algorithms, sometimes you need to set the flash manually to get the exact result you want. The 580EX gives you more control than its predecessors, with manual power selection in 1/3 stops from full power down to 1/128 power. This hands control back to the photographer in situations where the metering system could be fooled.

Custom functions
The number of Custom Functions has been increased from six on the Speedlite 550EX to 14 on the Speedlite 580EX. CF-1 to CF-6 are the same on both Speedlites − it’s from CF-7 onwards where changes have been made.

CF-7 and CF-8 are designed for shooting environments where speed is important. They allow you to recycle from internal and external power simultaneously, or fire when the lamp is yellow-green (i.e. not fully charged) respectively.

CF-9 and CF-10 give you control of test flashes, either doing a test fire or using the test button to fire a modelling flash.

CF-11 allows you to turn off the sensor size autozoom if, for example, you only use a full frame camera.

CF-12 turns the focus assist beam on or off − useful in circumstances where you don’t want to project a red beam onto your subject.

CF-13 controls the use of the command dial on the flash. For speed, you can set it so you only need turn the dial to set flash exposure compensation, instead of pushing the central button and then rotating the dial.

CF-14 allows you to disable the auto power off feature.

Speedlite 580EX II

Updating the Speedlite 580EX, the 580EX II offers faster, silent recycle times and a more durable build quality.

The Speedlite 580EX II improves on many of the specifications of its predecessor. The silent recycling, for example, is up to 20% faster.

Weather seals ensure that when attached to the EOS-1D Mark III, the Speedlite 580EX II achieves the same level of dust and moisture resistance as the camera itself.

A redesigned metal flash foot plate and connector pins allow more stable communication between the camera and flash, while a quick release mechanism minimises wear and tear on both of the units.

The flash head zoom covers the range 24mm to 105mm and an integrated diffusion panel allows extended wide-angle coverage to 14mm.

The Off Camera Shoe Cord OC-E3, Compact Battery Pack CP-E4 and Speedlite Bracket SB-E2 also allow sealing against dust and moisture, giving photographers a complete system to achieve off-camera lighting effects in difficult weather conditions.

Speedlite 430EX
The Speedlite 430EX flash unit replaced the 420EX. It improves on many of the specifications of its predecessor and includes new features to maximise digital image quality when using a flash. These include automatic selection of camera white balance settings and auto-adjustment of the zoom flash position to match the sensor size of the camera to which the unit is attached.

The Speedlite 430EX has an increased guide number of 43 (m/ISO 100 at 105mm) and has approximately 40% faster recycling time than the Speedlite 420EX. An ultra-bright 2-LED configuration focus assist-beam has been designed to be compatible with all focus points within the frame of EOS AF systems, up to 9-point AF.

Optimum flash coverage
The flash head zoom covers the range 24mm to 105mm and an integrated diffusion panel allows extended wide-angle coverage to 14mm. When attached to digital EOS cameras with smaller than full frame sensors the Speedlite 430EX gives a more accurate flash coverage by detecting the model to which it is attached and automatically narrowing the angle of coverage. This has the effect of eliminating light loss in peripheral areas and extending the effective flash range.

Ideal white balance
The Speedlite 430EX automatically transfers colour temperature information to recent models of digital SLR cameras. The camera then sets the colour balance optimally for the flash shot. This feature works when the camera’s white balance mode is set to auto white balance (AWB) or flash white balance mode, compensating for any changes to the Speedlite output caused by age or battery condition.

Other features
The Speedlite 430EX is fully compatible with the distance linked E-TTL II system found on recent EOS cameras, and supports other EOS cameras that do not have E-TTL II.

It also serves as a wireless slave when either the Speedlite 580EX, 580EX II, 550EX, Macro Ring Lite MR-14EX, Macro Twin Lite MT-24EX or Speedlite Transmitter ST-E2 is used as a master.

An intuitive and ergonomic interface includes an LCD panel for clear indication of modes and settings. A single bounce lock release button provides immediate control over the bounce head angle for flexible positioning of the flash head. The flash head can be moved up from 0 to 90° (five settings), left from 0 to 180° (seven settings) and right from 0 to 90° (four settings).

Six custom functions allow customisation of the flash operations. Despite high power and short recycling times, the unit is small and lightweight.

Other features include first and second curtain flash synchronisation, modelling flash, high-speed synchronisation (FP flash) and manual adjustment of flash output from full to 1/64 power (7 levels).

Speedlite 220EX

The Speedlite 220EX is a low-power flash gun for EOS cameras that do not have a built-in flash unit. It offers twice the power of built-in units, but only half that of the Speedlite 430EX. It is mostly useful for fill-in flash photography. The fixed head means that you need the Off Camera Shoe Cord for bounce flash photography.

No comments:

Post a Comment