550 give better fill-in than 580

[jacken]

These are my findings:
New 580 more accurate indoors. Outdoors it overflashes in fill-in situations. I reckon this is because it takes distance into account. I quite often shoot over 12 feet or more with long lens and 550 gave a better very light fill-in when compensation set to 2 stops under.
580 will over light these situations even when set to 3 stops under.
Any body else had this issue?
Is mine faulty. I've been stuglling for a year with this to the extent I carry two flashes, 550 for out 580 for in!!!!!!!!
I love the easier controls of the 580 however.

Hope to hear from you.

[PacAce]

Have you tried a side by side test of the two flashes. All the ETTL intelligence is in the camera and the flash only does what it is told. And the distance info also is used by the camera, not the flash, so that shouldn't make a difference.

If you do do the test and find that they are, in fact different, you can further refine the test by turning off auto sensor size detection, i.e. set C.Fn-11 to 1 on the 580EX, to see if that is making the difference.

[tim]

I've never noticed a difference between the two - I have one of each.

[jacken]

It is based upon weekly wedding work findings. ETTL II which my 1d mkII has will link the output of the 580 flash to the distance set with certain lenses. This feature will not work with the 550 as it does not have ettl II compatibility.
This is my understanding.
I will do side by side tests. Can I post photos on this forum - I am a newby here.

[PacAce]

It is based upon weekly wedding work findings. ETTL II which my 1d mkII has will link the output of the 580 flash to the distance set with certain lenses. This feature will not work with the 550 as it does not have ettl II compatibility.
This is my understanding.
I will do side by side tests. Can I post photos on this forum - I am a newby here.
550EX is fully ETTL-II compatible.

And, yes, you can post your test photos here. By all means, please do.

Oh, I was remiss in not welcoming you here (didn't realize that you were new). So welcome to the forum. :)

[jacken]

Thanks, good to be here.
Are you saying that the 550 will adjust power not only based on algorithms and matrix metering but also the distance transferred from certain lenses. This is not what I understood. It was one of the big selling points of the 580 as I recall.

[PacAce]

Thanks, good to be here.
Are you saying that the 550 will adjust power not only based on algorithms and matrix metering but also the distance transferred from certain lenses. This is not what I understood. It was one of the big selling points of the 580 as I recall.
Yes I am. The 550EX will output flash based on distance info just as the 580EX does, only because it's not the flash that's taking in that info and doing the number crunching. That's all done in the camera by the ETTL-II logic.

What the 580EX does give you is a tad more max flash output, head zoom based on sensor size, color temperature info sent to camera and a litte more ergonically designed control interface. If there's anything I missed, I'm sure someone else will chime in. :)

Oh, yeah, faster recycling time, too. :D

[jacken]

OK.
I'e just remembered when i enquired with Canon previously about this problem I was told that the 580 has done away with auto fill-in flash reduction (or something like that) which the 550ex has.
It must be down to this.
I am concerned nobody else has sen this over fill-in though...

It's such an issue with me I hope people wno't mind more posts as I find more out...

[cdifoto]

Don't forget the free catchlight card. :)

[Curtis N]

If there's anything I missed, I'm sure someone else will chime in.Leo, you left out:
Full swivel, 180° in either direction (first TTL flash with this ability).
AF-assist beam now compatible with all AF points on every EOS SLR.

Jacken, welcome to POTN. I hope you can get this issue sorted out.

On Canon's website page on the 580EX, there is no mention of E-TTL II. Leo is correctly pointing out that this metering system is compatible with all EX flashes.

[PacAce]

OK.
I'e just remembered when i enquired with Canon previously about this problem I was told that the 580 has done away with auto fill-in flash reduction (or something like that) which the 550ex has.
It must be down to this.
I am concerned nobody else has sen this over fill-in though...

It's such an issue with me I hope people wno't mind more posts as I find more out...
Auto fill flash is also a function of the body, not the flash. ETTL has it but ETTL-II did away with that. I'm assuming the camera you are using in this case is the 1DmkII which is an ETTL-II camera.