Flash Problems 580EXII

[Garry Gibson]

Here are two photos both taken with the same lens
at the same subject with the same flash.

The top image was taken with the Mark1I DS and
the bottom image with the 40D.

As you can see from the EXIF, the Flash fired on the
40D at O and on the DS at -1 2/3. Both were set on
ETTL.

I set both bodies to shutter priority, 1/250 and F4.

I don't know why the flash continues to improperly
fire on the DS.

Any suggestions?

thanks

Garry

[runninmann]

According to EXIF, the Mark II shot is with a 105mm lens and the 40D is with 35mm. Which metering modes did you use?

[Bearmann]

I can't see the EXIF. Did you have flash exposure compensation set at minus 1 2/3 on the 1DS? I don't know your experience, so please pardon me if it is obvious to you. Study your 1DS owners manual regarding setting flash compensation.

[apersson850]

I don't understand this either?
If the flash didn't fire at normal strength with the 1Ds Mark II, then set the flash exposure compensation back to zero and try again.
Or is there something else to this?

[Garry Gibson]

I turned the flash off before each time I moved from
camera to camera. I did not change it to minus -1 2/3.
I turned it on after it was installed on the different bodies.
All I did was turn it on and make sure it was on ETTL.

Same lens I tried to zoom to get approximately the same
field of view since one is crop and the other isn't.

I see nothing in the manual that would address this.
I have the DS metering set to Average instead of Evaluative
when it is using the flash. The only real custom function
I can see that refers to the flash.

[Garry Gibson]

Here are two more images in the darker one I made sure the ETTL
was set at zero. In the EXIF it shows - 1 2/3

When I set it in ETTL to +1 2/3 it shoots at +1 2/3

Sorry for being dense, but it makes no sense to me.

thanks for the comments, I appreciate you taking the time
to look

GG

[apersson850]

The camera will remember the FEC setting across power off and so on. If you move a flash, which by itself has FEC set to zero, between different camera bodies, the setting on the current camera will be used.
The flash will override the camera's FEC setting, if you set some value different from zero on the flash itself.Does any of these two bullets help you in any way?
If you have FEC set on the flash, there's an icon for that.
If you have it set on the camera, there's an icon in the viewfinder for that.

[Leonard Wong]

I think you are asking settings on the flash while set on the 1Ds2 changed when the same flash is plugged into the 40D. I don't have two bodies, bu I do have the 40D. I'm not sure if you know, but the 40D can set the flash camera settings in the body's menu system. Perhaps these settings are restored everytime the flash is plugged into the 40D's hot shoe and the flash/body is turned on? I'm just guessing tho.

[Garry Gibson]

Anders I will look for that right now.. I feel like it has to be a setting.
thanks for your help

[apersson850]

Comment to Leonard: Nope, these settings are not restored to whatever the 40D set the flash to last time that flash was used on that 40D.
Instead, these settings remain in the flash, power on or off (as long as the batteries stay in), and will be read by the 40D and displayed the next time the flash shows up on that camera again.

So if you set it up through the menu system on the 40D, then move the flash to the 1Ds Mark II, change something on the flash itself (you have to do that, as the 1Ds Mark II is too old to support flash setup through the menu system), then move the flash back to the 40D again and open the flash menu, you'll now see the settings you did on the flash itself while it was on the 1Ds Mark II.

[Titus213]

Nope, not reset. And if the FEC was set on the flash it would be the same on either body.

[apersson850]

Yes, but I got the impression that he (OP) got a correct result on the 40D, underexposure when the flash was moved to the 1Ds and finally overexposure on the 1Ds.
Which is logical, if we assume that:

On the 40D, no FEC was set on neither camera nor flash.
On the 1Ds, negative FEC was set on the camera but zero on the flash.
Finally, still on the 1Ds, positive FEC was set on flash to see if it made any difference. Which it did, since this now overrode the camera's setting.

[Garry Gibson]

okay that was the answer the FEC was set on the DS to - 1/2/3
Thanks guys for taking the time to answer... it really saved me a
lot of time and aggravation.

Garry

[Bob_A]

Yes, but I got the impression that he (OP) got a correct result on the 40D, underexposure when the flash was moved to the 1Ds and finally overexposure on the 1Ds.
Which is logical, if we assume that:

On the 40D, no FEC was set on neither camera nor flash.
On the 1Ds, negative FEC was set on the camera but zero on the flash.
Finally, still on the 1Ds, positive FEC was set on flash to see if it made any difference. Which it did, since this now overrode the camera's setting.

I agree.

If FEC on the flash is set to zero, the FEC setting on the camera is used. On the other hand if anything other than zero is set on the flash, the flash overrides the camera.