420EX problem

[Toogy]

I have an old 420EX flash that just doesn't seem to be working right. The flash fires but it doesn't seem to be working at full power. I bump up the FEC to +2 and it still under exposes the photo.

Any ideas on what I might try to fix it, or is it just toast? It is about 5 or 6 years old FWIW.

[msowsun]

Have you tried a higher ISO and larger aperture? ( ISO1600 f/2.8 )

If you can get it to overexpose with extreme conditions you might be able to determine whether or not it is working at all.

[apple]

Toogy,
Did you ever get a solution? I an experiencing the same situation and when I did a search, this thread popped up. Anybody else have an idea? thanks.

[apersson850]

Does it think it exposed correctly?
That is, does the lamp that shows correct exposure turn on after you took the image?
If so, something seems wrong with settings or metering (fault).
If not, there's not enough power, either due to settings or some fault.

[apple]

Thanks for the reply Anders. The only noticeable difference is that the ready light does not go off and I can take another flash immediately. I use center only for measuring and it does seem to occur more often when I use an omnibounce. It just doesn't seem to be consistent.

[apersson850]

Let's see, you mean that the pilot light is still on after the picture was taken, like if the flash had used very little power?
But what about the "flash sufficient" lamp then? Does that turn on for a few seconds, just after you took the picture?
What about FEL? Does the camera indicate that exposure will be sufficient when it's reasonable that it will? Does it then still not become sufficient, when the picture is actually taken?

[apple]

I just decided to do a little test to see if I could answere some of your questions. I took a couple of shot of my living room and checked . The flash sufficient light did not always come on. I decided to change out my rechargable batteries with a brand new set of cells. The flash sufficient light came on every time and all shots were decent. I am not sure how this might trick the capacitor into not firing right but it did. Serves me right for ,quite probably, trying to push the rechargables beyond their capabilities i.e. YEARS of use.:oops: