I have a Speedlite 580 that I use with the 1D MKII, and sometimes I get weird behavior with the flash.
I have it set on ETTL, and I just dial up and down the exposure compensation on the flash itself, while using the camera in either manul or aperture priority mode.
So the problem is this--when I point the flash directly to the front, even with it dialed down to -2, it still blasts the subject and totally blows everything out, but if I turn the flash to any other angle, it'll behave normally. What's up with that?
Also, what does it mean if a newly charged set of batteries makes the flash's indicator light turn red instead of the green it's supposed to show?
Also, what does it mean if a newly charged set of batteries makes the flash's indicator light turn red instead of the green it's supposed to show?
I guess you haven't owned other Speedlites or spent time with the manual have you? Red indicates the flash is fully charged and ready to fire. The green under it means the flash exposure was okay. If the green light doesn't come on, get closer.
My manual is in storage, so I don't have access to it for now (not until we find a new place to live). From what I remember, the red light is supposed to be green--to indicate that the flash is ready to go, and the light underneath it indicates if an exposure was good or not. Guess I remembered wrong. I actually use the flash a lot as a fill flash--I usually just dial it to -2 and then bounce it off of wherever I want and not have to think too much about it. Only when it's acting weird do I have to start worrying about it.
I checked the notch under the normal angle, and both that and the normal front angle overexposes the subject, while any other angle doesn't.
I don't have compensation dialed in on the camera.
I just tried more tests, and if I dial the ISO all the way down to 100, the exposure is closer to normal (but nowhere near the look of -2 flash, which is a very natural subtle fill-flash that I use all the time for low-light indoor shots that should look like it was taken without flash). I typically shoot shots like that with a setting of roughly f/1.4~2.8, 1/30~1/60, ISO 400~800, and flash of -2. The results I get typically look like this:
As you can see, the -2 on the flash makes the effect very subtle and gives a very natural look. I used to be able to get that look even with the flash pointed forward, but now I'm getting the subject completely blown out.
Check your contacts on your hot shoe. Make sure they are clean. Ensure when mounting the flash that you are seating it all the way into the hot shoe so your E-TTL gets to talk appropriately with the camera.
The negative 7 degrees on your flash head is for use when you are close to your subject and need some light lower in the frame.
Try setting up again the way you like to, then look at the back of the flash and see what range the 580EX says it is prepared to cover. If you are shooting closer than the minimum; Expect it to blow out unless you change your exposure settings. Since you like Av, lowering you ISO seems like the way to go. Since you have already determined ISO 100 will work, maybe you were withing the minimum flash distance.
I tried as you suggested--checking the contacts and all that--no difference. I tried shooting from longer distances too, and it's still blowing out the exposure. ISO 100 is not a choice since it'll kill all the ambient light, and the whole point of shooting in the style I do in the first place is to capture the intimacy of low-light ambiance.
Thanks for the link to the PDF--I'll see if I can find the answer in there.
I reckon the problem is with the Av mode. The camera is applying its own fill ratio depending on available light without flash. In manual that would not happen. Also, if the flash is not facing ahead that would not happen.
For what it's worth I have not had any luck with Canon Flash in Av mode. Manual works fine. I'm still not getting the consistent results I got from my former Nikon flash system FYI.
Manual mode doesn't help--I shoot in both Av and Manual mode and they both blow out with the flash facing the front. I've also tried different metering modes--still no difference.
Since you're not able to get back to where you were previously shooting with the flash, it only leave two possibles in my mind. (considering you've already checked contacts and seating of the flash) Ones is that something in the E-TTL circuitry in the flash has failed and the flash needs servicing, the other is that some circuitry in the camera body that coordinates with the flash has failed.
If you know someone else close to you shooting the same body; I'd check you flash on it. if it has the same problem it is the flash. If it doesn't, then the problem might be in your camera.
I can't think of any Custom functions that would cause this. As far as Av mode causing the problem, Av mode is designed for what you have been using it for; Fill flash of your subject with Ambient metering of the background. I like your photos demonstrating what -2 EC can do for you. A very nice intimate look.
Don't forget that EC adjustments on the flash override EC adjustments on the camera body.
I'll look at the Custom functions for the 580EX, perhaps there is something there we are all overlooking.
Have you changed your C.fn-14 from evaluative to average lately?
From what the manual for the 1D MK IIn says, evaluative is where you want it for your style shooting.
This is my last stab in the dark for now. I did not see anything in the manual for the 580EX that could cause this. (unless somehow you've managed to put your flash is manual full power and not notice it).
As long as your flash is in E-TTL and your C.fn-14 is in evaluative, I think we are back to a problem with either the flash or the camera.
If you get a chance to troubleshoot with someone that has similiar equipment, I'd be interested in what you learn.
Ken
Sorry, Ranmandx, I overlooked your coverage of C.fn-14 earlier.
Are you shooting with a zoom lens? I believe the 580EX flash has its
own head zooming function that tracks the focal length of your
zoom lens. This tracking function is deactivated when you move your
flash head off of dead center to a different angle. I expect it then
zooms to it's widest setting. Is it possible that the zooming head
on the flash is stuck at telephoto? You are getting more power to
the subject than your E-TTL system thinks you are, perhaps?
I've checked all the stuff you guys suggested--no difference.
I've shot with both zoom and prime with the flash and both behaves the same.
I'm not sold on the defective circuitry thing--but only because I'm such a wuss with my camera (as in, I never get too rough with it). But who's to say it didn't just wig out all by itself? I'll see if I can replicate the problem on another body (no one else ever had this problem before).
The zoom head on the flash is working fine--I checked it. Though I do wonder why it only misbehaves when it's facing forward (or that notch underneath).
What's strange is that if I bring down the diffuser panel on the flash (which automatically changes the zoom head to 14mm), the problem goes away and I get my lovely -2 subtle fill flash back. I tried this with both a zoom and prime lens. What does this tell you guys? I'm at a loss here.
Oh, I forgot to mention--I've had this problem before, and it just goes away by itself--which leads me to wonder if it's related to a certain set of batteries I use (which probably isn't is--since I just tried a different set/brand and same thing), or something else.
Could it be that you are just too close to the subject ?
If not then I agree with Ken that the flash unit and/or camera are at fault. We seem to have exhausted all likely user-errors. Test the flash as-is on another camera. Test another flash on your camera. Send the faulty bit(s) to Canon for service.
Looks like it'll have to be faulty circuitry then, since I've tried shooting from across the room too.
But that still doesn't explain why having the 14mm diffuser panel down fixes the problem (while simply dialing down the zoom head to 24mm doesn't change anything).
Not sure why the diffuser panel makes a difference, although it does bring us back to the possibility that the flash is not recognizing when the diffuser panel is not in use, hence your good exposures with the panel deployed.
In the manual for the 550EX, it says if you pull the wide panel out too far the zoom button will not work and the entire display on the lcd will blink, put the panel back in, the zoom button will work, but the entire display will continue blinking. Send the flash to Canon for repair.
In the manual for the 580EX , page 20, it tells you that if you accidentally detach the wide panel, the zoom function will not work, the display will blink and then tells you how to reset it. Next it tells you the flash will work normally.
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