550 focus-assist beam quit on me

sara505

I was shooting an event the other night in a hall with very dim light. I was freaking because for the first half hour, 9 out of 10 of my shots were out of focus - I know the 5Dmk II is slow to focus in low light, but this was ridiculous. I called my friend Sam who asked, does the red focus-assist beam appear when you're focusing? I discovered it was not, and in the heat of the moment could not find a fix. I ended up using my 430 on-camera and threw the 550 on a light stand - no focusing needed - and it all worked out, but I would love to know how to get that red beam back.

I have the manual, but can't find the answer.

Anybody know?

ziggy53

Thanks goodness you had the backup flash. clap

I'm afraid that if the 430EX "was" producing an AF assist beam then it would appear that the 55EX AF assist beam has failed and may need repair.

The AF assist is triggered from different contacts on the bottom of the flash, so you could try cleaning and scrubbing the contacts to eliminate that as a source of the problem.

I use a plain white facial tissue ("Kleenex" is the typical term in this country) to start and then a fresh red rubber pencil eraser rubbed against the shoe contacts. I finish with a plain white piece of paper on a semi-hard surface, gently scrubbing the flash contacts on the paper.

If cleaning the contacts does not work, and if you're sure that the camera was not in AI-Servo focus mode (worth double-checking), then I recommend sending the flash in for repairs of the AF assist light.

sara505

ziggy53 wrote: »

Thanks goodness you had the backup flash. clap

I'm afraid that if the 430EX "was" producing an AF assist beam then it would appear that the 55EX AF assist beam has failed and may need repair.

The AF assist is triggered from different contacts on the bottom of the flash, so you could try cleaning and scrubbing the contacts to eliminate that as a source of the problem.

I use a plain white facial tissue ("Kleenex" is the typical term in this country) to start and then a fresh red rubber pencil eraser rubbed against the shoe contacts. I finish with a plain white piece of paper on a semi-hard surface, gently scrubbing the flash contacts on the paper.

If cleaning the contacts does not work, and if you're sure that the camera was not in AI-Servo focus mode (worth double-checking), then I recommend sending the flash in for repairs of the AF assist light.

bowbow Ziggy!

That's exactly what happened. I guess, while stumbling around in the dark, adjusting ISO, I accidentally switched to AI Servo.

All fixed!

Learned something!