580EX/430EX issues

saw this in RG and here. basically what it says is no matter how small the focal length reported by the lens, the flash unit would never set a head position "wider" than "35 mm"

anyone having similar issues?

If the widest lens the 580EX can be used with (without using the wide panel) is 24mm, why would you need to go wider than 35 on a 1.6x camera?

hmmm, mine goes all the way down to 24mm (as mentioned in the userguide), and any wider coverage (14mm) has to be assisted by the pullout fresnel lens.

The number that shows on the LCD is 24mm but if you have the "crop factor" thing enabled via custom function (and this is the default), then the head is really positioned at the 35mm zoom position when used with a 1.6x camera. The only way to tell if you're really at 24mm or the "cropped" zoom is by looking at the little box-like icon on the flash LCD.

bokehed wrote:
=bokeh'ed]saw this in RG and here. basically what it says is no matter how small the focal length reported by the lens, the flash unit would never set a head position "wider" than "35 mm"

anyone having similar issues?

For the 580EX used with a 20D:

I just read the links you pointed to. I have both an earlier model S/N136XXX purchased in Dec 04 and a later model S/N237XXX purchased in Aug 05. They exhibit the two responses "X" and "Y" as described by Doug Kerr.

It bothers me little abit because the more recent 580EX covers the ranges more optimally and the older one doesn't. It would be nice if both operated in the same way on the 20D. However, I hadn't realized they were different until now. I'll probably set the older flash's CF 11 to "non-compensated".

On my film body:

Both flashes act the same way at focal length settings of 16-200mm. (using various lenses across the range)

The link to Doug's chart, which makes testing this easy, is broken - it's here.

My 580EX was bought in October 2005, but has a relatively low serial number of 2058xx. It exhibits Behaviour Y. I wonder if 200000 was the changeover point.


I've emailed details of my setup - 20D with 2.0.3 firmware, EF 24-70mm f/2.8L lens and the full serial numbers of both the body and the flash to Doug Kerr. The extra step at 44mm on the zoom ring was audible, confirming Behaviour Y.

David

Just revisiting this topic with an update... I called Canon and they have a service (repair) available for 580EX speedlites that are not zooming correctly with wide-angle lenses when set to the "Sensor Size Compensation" setting.

If you want this feature corrected (in the US), call 1-800-OKCANON to file a service request.

Edit: May 22, 2006 - Canon service was fast. They made the changes to my flash and it now compensates for zoom the same way that the later serial numbered units do.