Canon 20D Flash Underexposure

"John McWilliams" wrote in message
...
{FU set to r.p.d.}

Skip M wrote:
Oh, Canon is aware of it. It is a consistent problem, not only with the
20D, but with the 1D mkII. I think it is a fault in the new ETT-L II
cutting the power of the flash too much in relation to distance to
subject. But that's just my theory.
I returned the 580EX we bought, because it didn't solve the exposure
problem. We get excellent exposures with the Quantum T4D flashes that we
rent, but my wife wanted something a little less bulky for general
photography. My 420EX seemed inadequate, but the 580 was no improvement.


Is there any difference in using ETTL with the camera in auto mode vs.
manual in terms of the underexposure problem? I am still experimenting
with the 550EX and the 20D.

I may go to all manual, as I'd just as soon the screwups be mine vs. the
camera's.

--
John McWilliams

Well, manual seems to solve the problem, since you are controlling the
exposure, not the camera. That's how pretty much everyone who say they're
not having problems are shooting.

--
Skip Middleton
http://www.shadowcatcherimagery.com

Does setting flash exposure compensation overcome the problem?

Paul

Does setting flash exposure compensation overcome the problem?

Paul

"(nospam)ruizpaul" wrote in message
...
Does setting flash exposure compensation overcome the problem?

Paul

Sometimes, but exposures vary too much to rely on it.

--
Skip Middleton
http://www.shadowcatcherimagery.com

"(nospam)ruizpaul" wrote in message
...
Does setting flash exposure compensation overcome the problem?

Paul

Sometimes, but exposures vary too much to rely on it.

--
Skip Middleton
http://www.shadowcatcherimagery.com

Skip M wrote:
"(nospam)ruizpaul" wrote in message
...
Does setting flash exposure compensation overcome the problem?

Paul

Sometimes, but exposures vary too much to rely on it.

--
Skip Middleton
http://www.shadowcatcherimagery.com

Skip,

I agree that it's not consistant enough to use or count on. I did a
photo session with my grand daughter dressed up and the 550 flash
worked about as good as it ever has on the 20D. They weren't under
exposed and a few were even over exposed. The problem is I never know
what I'm going to get until after and it's very frustating. I had the
meter set to partial and I don't know if that helped or not. I will
continue to work at it and see if manual exposure is the only way to
take consistant flash shots.

Art

Skip M wrote:
"(nospam)ruizpaul" wrote in message
...
Does setting flash exposure compensation overcome the problem?

Paul

Sometimes, but exposures vary too much to rely on it.

--
Skip Middleton
http://www.shadowcatcherimagery.com

Skip,

I agree that it's not consistant enough to use or count on. I did a
photo session with my grand daughter dressed up and the 550 flash
worked about as good as it ever has on the 20D. They weren't under
exposed and a few were even over exposed. The problem is I never know
what I'm going to get until after and it's very frustating. I had the
meter set to partial and I don't know if that helped or not. I will
continue to work at it and see if manual exposure is the only way to
take consistant flash shots.

Art

"Fyimo" wrote in message
oups.com...

Skip M wrote:
"(nospam)ruizpaul" wrote in message
...
Does setting flash exposure compensation overcome the problem?

Paul

Sometimes, but exposures vary too much to rely on it.

--
Skip Middleton
http://www.shadowcatcherimagery.com

Skip,

I agree that it's not consistant enough to use or count on. I did a
photo session with my grand daughter dressed up and the 550 flash
worked about as good as it ever has on the 20D. They weren't under
exposed and a few were even over exposed. The problem is I never know
what I'm going to get until after and it's very frustating. I had the
meter set to partial and I don't know if that helped or not. I will
continue to work at it and see if manual exposure is the only way to
take consistant flash shots.

Art

My theory is that it is related to the distance to subject logarithm in the
ETT-L II. I think that the flash is reduced, as it should, but it reduces
it too much to keep the foreground part of the depth of field from being
overexposed. So, when you have a shallow depth of field, the exposures are
correct, or at least more correct. More depth of field, more compensation.
Mind you, this is only my thinking on it, based on a few images that I've
shot with Canon flashes that this was observable.

--
Skip Middleton
http://www.shadowcatcherimagery.com

"Fyimo" wrote in message
oups.com...

Skip M wrote:
"(nospam)ruizpaul" wrote in message
...
Does setting flash exposure compensation overcome the problem?

Paul

Sometimes, but exposures vary too much to rely on it.

--
Skip Middleton
http://www.shadowcatcherimagery.com

Skip,

I agree that it's not consistant enough to use or count on. I did a
photo session with my grand daughter dressed up and the 550 flash
worked about as good as it ever has on the 20D. They weren't under
exposed and a few were even over exposed. The problem is I never know
what I'm going to get until after and it's very frustating. I had the
meter set to partial and I don't know if that helped or not. I will
continue to work at it and see if manual exposure is the only way to
take consistant flash shots.

Art

My theory is that it is related to the distance to subject logarithm in the
ETT-L II. I think that the flash is reduced, as it should, but it reduces
it too much to keep the foreground part of the depth of field from being
overexposed. So, when you have a shallow depth of field, the exposures are
correct, or at least more correct. More depth of field, more compensation.
Mind you, this is only my thinking on it, based on a few images that I've
shot with Canon flashes that this was observable.

--
Skip Middleton
http://www.shadowcatcherimagery.com

If that's the case, then opening the lens would TEND to cure the
problem. And if so, Canon should be telling us about. I find their 20D
manual to be highly inadequate. You pay $2000 for an outfit and get that
little 160 page pocket "guide". I hope somebody writes a comprehensive
manual sometime soon.

Paul