This article is based on what I gleaned
in one week of use of a borrowed Yongnuo Canon mount 568 EXII flash.
I tested as many features as possible in the time permitted with the
emphasis on the features most important to my own usage. I had a
Canon 580 EXII and Canon 430 EXII flash units on hand to compare.
Test cameras were Canon 20D, 7D and 70D.
The Yongnuo 568 EX II is about the same
size and weight as the Canon 580 EXII but is not a direct copy, the
case shape and finish is different, the LCD display though similar in
size has a unique layout. The main command dial is a four quadrant
unit rather than the rotary unit of the 580EXII.
Hot shoe mount: Uses the older rotary wheel method that
Canon used two generations ago rather than the quick release system
currently used. I prefer the wheel overall as myself and others have
found the quick release system to be unreliable at times with the
flash able to slide back enough that it looses communication with the
camera or falls to the ground. This is partly due to not insuring
that the flash was installed into the shoe completely and the
additional stress that diffusers and tele extenders place on the hot
shoe, the wheel system seems to be more secure. I noticed though that
the Yongnuo spring loaded locking pin is smaller in diameter than the
Canon ones but there was no more side to side play when mounted on
the shoe than the Canon unit.
Zoom head:
Covers the same range
as the Canon 580 EXII, 14mm -105mm. Indeed the front Fresnel lens
looks identical to the Canon flash. It uses a 14 mm pull out lens and
catch light card also. The zoom head will track a zoom lens or can be
zoomed manually.
Power output: High flash power
is critical to the way I use flash as fill in sunlight nature images.
The power level was compared to the Canon 580 EXII and 430 EXII and
found to be within +- .3 EV on most zoom head settings. Indeed at
105mm it was .3 EV more than the 580 EXII.
Recycle time: A remarkable
surprise here. My work using flash to shoot outdoor action requires
the shortest recycle times possible. Back several years ago most
flash units without an external battery pack required 6 seconds or so
to recharge after a full power pop. When Canon came out with 580 EXII
and 430 EXII I was impressed as these units would recycle in about
2.5 - 3 seconds with fresh batteries 1. I found that a full power pop would
recycle the 568 EXII in about 1.5 - 2 seconds! At first I assumed the
red ready light coming on quickly was premature and that the flash
had not really recharged fully but in testing I found the lamp did
reflect that the flash was fully charged as proven by the image
histogram.
ETTL: Testing the flash in auto
exposure ETTL mode on both the 7D and 70D showed reasonably
consistent exposures with changes to aperture 2.
Compatibility with older cameras:
There were some reports on the Internet
of incompatibility with some Yongnuo flashes and older Canon cameras
models. I tried the 568 EXII on my old 20D camera and it appeared to
expose and operate properly.
Auto focus assist:
The auto focus assist pattern is brighter and more concentrated near the center on the 568 EXII
compared to the Canon 580EXII which is dimmer but much wider. However
there did not seem to be any difference in performance when tested in
a dark room at 30 feet.
LCD display: On the 568 EXII the
LCD display needs to be viewed straight on or from below for maximum
visibility, if it is viewed more than a few degrees from above it
looses contrast and is hard to see.
Sound:
Unlike the Canon flash a number of
beeps can be used to indicate when the flash is ready, exposed
correctly or battery is low. This can be of value as it provides
information without the need to look away from the viewfinder image.
A button press disables\enables the sound.
Command controls.
Controls consist of four push buttons
and a command quadrant control used for exposure compensation with a
mid SET button which works but is not quit as easy to use as the
rotary command dial of the Canon 580 EXII, but much easier than the
awkward 430 EXII control.
Head Positions:
The head positions are rotate, tilt and
lift same as the Canon 580 EXII but without an unlock button which is
not really needed in practice anyway. A tilt down LCD icon is
absent unlike the 580 EXII.
Modeling flash:
Much brighter
on the Canon units. I seldom use this but if I need to find
my car keys in the dark it makes a convenient flash light.
Distance scale or readout:
There is no distance indication at all,
I use this feature to estimate how close I need to be to the subject
for long distances and regret that it is missing, both the Canon
flashes have this feature though the 430 EXII shows maximum distance only, not minimum.
Pulse width:
According to the instruction manual the
568 EXII has a light pulse width of ~1/200 ~ 1/20,000 seconds. This is
much slower than the Canon flashes which start at 1/000 second or so.
I find this odd but it is probably not a problem for fill flash
usage.
Water resistance:
I have no idea how water tight it is.
The rubber boot which keeps water from the hot shoe on the Canon 580
EXII is not used as the wheel mount system precludes it though water
on the hot shoe has never been a significant issue in my experience.
All my Canon flash units have been exposed to rain at some time
without fail though they are not sealed completely and I try to cover them
in heavy rain. The case on the 586 EXII seems similar, time will tell
how it survives in the rain.
Camera menus and Custom functions:
The camera flash menu system worked ok,
the flash custom functions menu though would only allow a few custom
setting to be set from the camera as Canons custom functions and
Yongnuo are different. However these can be set easily in the flash
unit itself and these settings are retained with power down so no
issue there. Older cameras like the 20D of course do not have a flash menu item in the camera anyway.
High Speed Sync and rear curtain
sync:
Both features worked fine, the High
speed sync had a similar power level as the 580 EXII.
Optical communication:
I was able to use the 568 EXII as a master to remotely fire a Canon 430
EXII as slave. The Yongnuo user manual claims a much greater range than
Canon but this was not tested.
User manual:
The manual consists of 33 pages in English and is much less detailed than a typical Canon flash manual
Cons:
- No distance scale
- LCD readout viewing angle is critical
- No connection for an external battery
pack to speed recycling
- No local repair facility
- No threaded mount (580EXII has this)
All
in all I was quit happy with the
operation of the flash unit. There was nothing that was a deal
breaker for my usage though I would like them to add a distance
scale. There is no connection for an external battery pack which is odd
as Yongnuo make one for Canon flash and it works with some of their
other flash models. The Canon 430 EXII currently costs about $90 more
has a
distance scale, is smaller and lighter and has a one year warranty.
As of now the Canon 580EXII is no longer available having been replaced with the 600 EX-RT $500. Time will tell if the 568 EXII has a satisfactory track record in the
field and if repairs can be had reliably from China.
Notes:
1 -
Recycle time was the average of ten full power pops, with the
flash fired as soon as the red pilot lamp came on. The histogram was
checked to make sure the flash fired at full power for each cycle.
Batteries were fresh Maha 2700 mAHr NiMh rechargables.
2 - ETTL mode was tested for exposure accuracy with a mid toned gray target at apertures from f2.8 - f22.
