flash power ETTL

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bluesilver

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Hi,

I have been having this issue for a while and for the life of me I can't get it to work properly. I put a 430 or 580 speedlight on my 7d and set the flash to ETTL , press the shutter release half way down and then fully to take the photo, but the flash power doesn't seem to evaluate the lighting required at all. I tend to get far too much power for some reason.
I'm probably doing something completely stupid :bonk: but I'd love some help.
 
Is the Answer in your question ?

"doesn't seem to evaluate the lighting" - What metering setting are you using ?

Have you adjusted the Flash Exposure Compensation?

Have you adjusted the Exposure compensation ? - Particularly if you are in the high shutter speed area (Way above sync speed)

Are you asking too much of your flash ?

Just a few to be getting on with ;)

Phil
 
Is your subject against a dark background? The flash is likely to be fooled by 'non average' scenes causing over exposure if a large part of the frame is very dark, or under exposure in the case of a large area much brighter than your subject.
 
Thanks both. It's probably me be stupid.

I think my camera metering was on evaluative.
I really noticed is when I was at the beach last week. I wanted to use an f-stop from the F11 to F22 region to darken the sky and use the flash to fill the people in the frame, but it just blew the whole scene. I was about 10-15ft from the subjects. I then tried to set it manually by putting the flash on it's lowest setting but that didn't help much either - it just blew the scene again.

I set the exposure compensation to 1stop under.
 
I've just read your question again......:bonk:

The scene is being over exposed? Also have a look to if the HSS is switched off (on the flash...)

Phil
 
Can you confirm what setting you had on the camera, AV, M (I assume AV or M if you changed the F/stop)

Did you check the flash Exposure compensation was set to "0",
Did you check the shutter speed,
Did you check the ISO,
Do you have the picuture still with the metadata as we could have a look-see.

Dan.
 
cheers Danzaroonie,

I had it on AV and on Tv depending on what I was going for in shot.

Exposure compensation was set to 1stop under I believe.
ISO was 100
Shutter speeds were getting ridiculously high at some points when in AV.

I might have the raw file data at home but I'm at work at the moment so can't access it..

HSS - I honestly can't remember if this was on or off.. but if I was hitting really high shutter speeds then I assume this would have been off..?

So, if I had it on ETTL and HSS would that have been the right setting?
 
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If you were using AV/TV then the flash will only fire for "fill-in" purposes.

Try using P mode and see if that imporves things and if so, recreate the settings in full-manual and take it from there ;)
 
ok, I'm confused now... I only shoot in AV or TV and it blew the whole scene at worst and blew the skin tones out at best..
 
If you could post some examples up it might be useful :)
 
bluesilver said:
Thanks both. It's probably me be stupid.

I think my camera metering was on evaluative.
I really noticed is when I was at the beach last week. I wanted to use an f-stop from the F11 to F22 region to darken the sky and use the flash to fill the people in the frame, but it just blew the whole scene. I was about 10-15ft from the subjects. I then tried to set it manually by putting the flash on it's lowest setting but that didn't help much either - it just blew the scene again.

I set the exposure compensation to 1stop under.
Click to expand...

Without seeing the image & not being familiar with Canon cameras/flashguns, this is my 'guess' at the scenario......

Subject meters at say 1/500 at f11 but you want to expose f22 for sky, so you set camera in aperture priority to f22, you turn your flash down -1 (as per your post) so the flash is effectively lighting at f16, still over-exposing your subject by +1 stop.... but here is where I think the REAL problem may lie....

.....when you put a flashgun onto the camera in AV, does your camera automatically set a default shutter speed of say 1/60th sec when it actually still needed to be 1/500th? If it does this will be the cause of your massive overexposure??

There is probably a menu where you can override this setting, otherwise you will need to revert to shooting in manual.
 
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Thanks Chip, I really appreciate your help.

I was under the impression that ETTL would sort out the exposure levels automatically so that it would fill in areas without me having to do too much?

Ok. How about this scenerio.

I meter for the sky at say, 4.5 and it gives me a shutter speed of 1/500 for correct exposure. I then stick it into manual and put aperture at 4.5 and shutter to 1/500. Now, to fill out any shadows in the people facing me (with he sun behind them) would I be best to

(a) stick the flash on a low setting and build up the power?

Or

(b) should I stick it in ETTL + HSS and shoot that way?


This photography lark can be frustrating at times....
 
bluesilver said:
Thanks Chip, I really appreciate your help.

I was under the impression that ETTL would sort out the exposure levels automatically so that it would fill in areas without me having to do too much?

Ok. How about this scenerio.

I meter for the sky at say, 4.5 and it gives me a shutter speed of 1/500 for correct exposure. I then stick it into manual and put aperture at 4.5 and shutter to 1/500. Now, to fill out any shadows in the people facing me (with he sun behind them) would I be best to

(a) stick the flash on a low setting and build up the power?

Or

(b) should I stick it in ETTL + HSS and shoot that way?


This photography lark can be frustrating at times....
Click to expand...


I would say choose option (c) - Use Av on Camera, leave flash in Ettl, Ensure Evaluative metering is selected and flash is in HSS mode (If metered shutter speed is above sync speed)

I understand that 'Fill flash' works at it's best in Av/Tv mode......

You can get great results using both the camera and flash in Manual, but it would seem that you could do with starting with this....

Phil
 
You need to use HSS for daylight flash as 1/250 is normally not quick enough.

Still not really sure why the flash over exposed as based on the information you supplied then it should have applied a fill flash to the shot…if anything you might have needed to up the flash compensation.


An example shot is going to be needed to really confirm.
 
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bluesilver said:
cheers Danzaroonie,

I had it on AV and on Tv depending on what I was going for in shot.

Exposure compensation was set to 1stop under I believe.
ISO was 100
Shutter speeds were getting ridiculously high at some points when in AV.

I might have the raw file data at home but I'm at work at the moment so can't access it..

HSS - I honestly can't remember if this was on or off.. but if I was hitting really high shutter speeds then I assume this would have been off..?

So, if I had it on ETTL and HSS would that have been the right setting?
Click to expand...

^^^ This.

Pretty sure your beach problem was the shutter speed needed to rise above x-sync (1/250sec) and would have been flashing at you in the viewinder as a warning, but you missed it. With the flash on, but without HSS enabled, it will not go above 1/250sec so the whole scene has been over exposed.
 
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