5D is the bomb.

Maybe it is a flash coverage issue rather than a lens/sensor issue?

Alex

I have noticed unevenness with land flash as well. It isn't just the corners, all around the parameter. It is quite annoying - center of the picture over exposed - the edges exposed properly or the center exposed properly and the edges underexposed.

I have found that it is a problem with the flash not the camera. Place the diffuser on the flash and the problem goes away.

Big deal 

Once I checked my Canon S50 housing in the pool, the only problem was that I forgot to put the O-ring back in its place, the not so surprising result was that the housing was half full in water in 2 second.

After I took out the camera and dried a little its worked but with some problems for some time and then stopped to operate at all, After 2 days just before the official funeral I wanted to give the camera the last chance and walla, resurrection! the camera work as new.

So who need 1D?? S50 is good as 

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There's a $3500 difference though... mine kept on working immediately. 2 days later it might miss an important shot or 2. And to be honest, I didn't drop it, I fell into the river and it joined me. However, I am the guy who's known to shower with the camera(not literally speaking) after a day of sea spray. I usually clean it with distilled water if I can.

The best chances of resurrections is really to take out the battery, put it in a low humidity room to dry and hope nothing was fried. However even the 1D sealing is not insurance against a flood. Never dunked it in salt water so I don't know how it fares against sea salt. Nor do I want to find out. Maybe someone else with a 1 series can experiment for us?

I have noticed unevenness with land flash as well.  It isn't just the corners, all around the parameter.  It is quite annoying - center of the picture over exposed - the edges exposed properly or the center exposed properly and the edges underexposed.

 

I have found that it is a problem with the flash not the camera.  Place the diffuser on the flash and the problem goes away.

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Which flash are you using? 550EX?

The 550 and 580 flashes can only zoom out to 24mm coverage. To get wider coverage than that, you need to flip down the diffuser. I think the flash displays 16mm after you flip the diffuser down.

It's taking me awhile to get used to having a FF sensor

I am useing a Sigma 500 super flash and a 50mm f/1.4 lens. I just did a test on a white wall.

1st: no flash

2nd: Flash set to 50mm

3rd: Flash with diffuser (17mm)

1 and 3 are nearly identical. There is some edge darkening but it is not too bad.

2: edge darkening is more noticable. The difference between the center and the edge is about twice as strong as in 1 and 3.

Conclusion the light coming from my flash is not completely even when the zoom head is set to 50mm.(I suspect that all flashes show similar light fall off away from the center.) This is made more noticable since the lens is vignetting a little to begin with.

Its really not that bad. Once I realized what was happening it is easy to avoid...all just part of learning a new system.

I tried the 24-70 2.8L lenses. Most shots were 2.8 - 4.

I was playing with the 100 2.8 today and it was not perfect but better than what I get with the 10D.

The 550 and 580 flashes can only zoom out to 24mm coverage.  To get wider coverage than that, you need to flip down the diffuser.  I think the flash displays 16mm after you flip the diffuser down.

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It's 14mm when the diffuser is down. I tried the 580EX with the 1Ds2 and the 24-105. Shooting ETTLII mode, I didn't see any uneveness. Does the Sigma support ETTLII?

Does the Sigma support ETTLII?

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The Sigma 500 super DG does ETTLII. I have the older 500 super (no GD) which is ETTL(1). The camera is backward compatible though. It works just as well with an ETTL(1) flash as any ETTL(1) camera would.

As long as my 550EX works with my 24mm I'm good. Will most likely pick one up after my Thanksgiving dive trip to BVI. Not sure if Ikelite will have 5D housing by then. 5D will benefit my Aurora Borealis trip more.

When does the Ikelite housing come out? Anybody know?