Canon 540EZ Operator's Manual page 3

EOS Documentation - 540EZ Operator's Manual Pagina 3 di 4
Other Controls
On the back, just above the LCD is the swivel release. Push it before swiveling the flash head from
straight forward. On the right side at the center of the tilt joint there is the tilt release button to be
pressed before raising the flash head. This combination of swivel and tilt allows the flash to be
bounced off the ceiling or wall regardless of whether the camera is held in a horizontal or vertical
position. The head can also be pointed down 7 degrees for close objects.
There is a pull out flash diffuser just above the front lens of the flash. It is rated to cover the
viewing area of an 18mm lens. This is somewhat over rated but it is a nice feature. When you pull it
out the flash will automatically zoom to its widest position. Its guide number is reduced to 52 feet
with ISO 100 film.
When you are using the flash to bounce off the ceiling the flash diffuser can be pulled almost all the
way out but not pulled down over the flash lens. This way, with your flash pointed straight up, the
diffuser acts as a small bounce card to reflect some of the light directly into your subjects eyes for
both shadow reduction and catch lights.
On the front of the Speedlite there is a near infrared auto focus assist light. It is good up for to
nearly 50 feet coupled with the EOS 1n's center AF point and a 50mm f/1.4 lens. It enables the side
AF points as far as 20 feet. On most EOS cameras this AF assist light will be used instead of the
one on your camera, but on the EOS 5/A2e/A2 and EOS 10/10s models the camera will continue to
use its own AF assist light.
The 540EZ also has a flash foot locking pin that mates with a hole in most Canon flash shoes. This
keeps the flash from slipping back and loosing connection with some of its contacts. By partially
screwing down the locking ring you can lower this pin before attaching it to the camera and still
slide the flash on quickly and securely.
Power Options
AA batteries
This flash uses 4 AA Alkaline, NiMH or NiCad batteries.
NiCads offer the fastest recycling. 4-6 seconds until nearly exhausted, which usually happens
between 80 and 140 cycles, depending on the MiHr rating of the battery.
Alkalines last the longer if you are patient enough for the slow recycles. They Start out at 8 seconds
but after 20 pops it's down to 11 seconds. After 70 it takes over 15 seconds and speed continues to
decline until at 200 cycles it takes 45-60 seconds, depending on how warm the batteries are. They
will continue beyond this, but what's the point?
NiMHs offer recycles nearly as fast as the NiCads. I recorded 4.5 to 5.5 seconds for the first 120
full power cycles with 1300 MiHr AA's. At 150 cycles it was still just 8 seconds and they continued
to the 170 mark where it took a full 40 seconds to charge. These have power characteristics that are
very similar to NiCads but last longer.
Lithium AAs can be used for the 540EZ as well. They last longer than other AAs and cycle the
flash somewhat faster than Alkalines (7 seconds for fresh ones).
All of my recycle tests were done with full power pops in manual mode, timing to when the red
indicator light first came on. A full power recycle actually takes about 50 percent more time and
provides about ½ stop more light according to my flash meter.
External Battery Packs
Quantum offers 540EZ adapters for the Battery 1, 1+, 1 Compact and Bantam external batteries.
The same adapter is used for the 550EX. These are 6 volt external batteries that have a dummy