Speedlite 600EX-RT fires but photos almost black

[light_is_magic]

Hi all,

I have a problem with one of my 600EX-RT flashes. In ETTL mode the pictures are almost black (despite the flash is firing) in Manual it seems that even set to 1/128 the flash is using full power. I already tried to clean all the contacts, still the same behaviour.

Any ideas?

regards

[TCampbell]

Have you dialed down the Flash Exposure Compensation?

On the back LCD, just below where it says "ETTL" in the upper left corner, it might show an icon with a lightning bolt and a +/- followed by a number.  If the flash exposure compensation is not set (basically it's set to "0") then it wont show that icon nor the value, but if any flash exposure compensation is set, you'll see the icon and the value that it's set to.  

If you were set to -3, your flash would fire at 1/8th the power that it thinks it needs (which would result in very dark images.)

The press the +/- button along the bottom (on menu page 1) and you can dial it back to 0 (if indeed that is what happened.)

It's also possible to change it in the camera.

But what I don't get is why changing the mode to manual and dialing down the power to 1/128th would result in firing at full power.  That might require service (or at least a phone call to Canon service to ask questions.)

[light_is_magic]

Hi,

thanks for your answer.

No, FEC is set to zero. I tried it with settings fom -3 to +3 also, same result. I got full power on EXT-A and EXT-M, regardsless of the settings, too.

Over all, it seems that no power regulation - automatic or manual - is not working. It's a holiday today, but I will contact my nearby Canon support tomorrow.

regards

[RobertTheFat]

I'm surprised that the OP can say with certainty that the flash is firing at full power, given that the originl complaint was that images are drastically underexposed.

[ComicDom1]

I would do a complete reset on the misbehaving 600EX and go from there. Usually that is the best place to start from.

Jason

[light_is_magic]

Hi,

is there a secret reset function I'm not aware of other from pressing button 2 and 3 for some seconds? Did that, no change.

regards

[ComicDom1]

I believe you can also clear your flash settings in one of your Camera Flash control menu if your Flash is mounted on your camera as shown on page 45 in the manual.

Once you do that in your Camera flash setting menu set your flash control from Evalutive to Average and see if that changes anything for you. If that does not change anything then I suggest you might give Canon Tech support a call at 1-800-OK-Canon and let them help you get it worked out. They are pretty good.

The other reset you are talking about is on page 38.

Make sure you have the diffusion panel pushed all the way back into the head of the flash. 

Is the head of the flash pointing forward or backward?

What lens are you using?   Is it a Zoom?   With the flash mounted on your camera and set to ETTL, is it in A mode or does it show something different?  If you have a zoom is the head of the flash zooming with the lens?


Post back and let us know how it went.

Jason

[light_is_magic]

When set to ETTL the images are without flash impact - despite there is flash triggered.

In all other modes - Manual, EXT-A, EXT-M - the images are totally overexposed, white-out. Well, maybe not full power, maybe 98%.... 😉 Do you feel better now?

regards

[RobertTheFat]

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@light_is_magic wrote:

When set to ETTL the images are without flash impact - despite there is flash triggered.

In all other modes - Manual, EXT-A, EXT-M - the images are totally overexposed, white-out. Well, maybe not full power, maybe 98%.... 😉 Do you feel better now?

regards

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You mentioned other 600EX-RT flashes. Do any of them exhibit the same behavior, or just the one?

[light_is_magic · Accepted solution]

Hi,

no, my other flashes work as expected. I talked today with my Canon Pro Dealer, and concluded to send the flsh to the Canon service center. The flash is still in warranty time, so let them check this out.

Just some more information: cameras were 2 5D3, the lenses I tried a 70-200 2.8 II and a 50mm 1.4. The flash shows the same behaviour triggered over radio.

regards