What would cause this?

[SnowA]

Taken this weekend with my 30D with the EF 70-200 attached. The same appeared on some shots earlier in the day with my EF-S 17-55 on it, so it appears to be an issue with the body rather than one lens.



Thanks in advance.

[RaoulIsidro]

Where you using flash on these occasions?
It could be the light bouncing of the condensation coming from your breath or atmosphere.
Condensation vapours are invisible but with fill in flash they sometimes exhibit this phenomena. It is like a mini rainbow.

[SnowA]

No flash. Very bright, midday sun.

You might be onto something there with condensation; I will try to replicate it sometime soon in bright sunlight again.

[etherial]

Any chance you didn't have you eye to the viewfinder and light was getting in there? Only other thing I can think of is a crack in the body somewhere.

[SnowA]

I don't think there was anything different to how I shot that day. A bit worried that there might be a crack.

[MarkChap]

The Sun, Did you have your lens hood on ??

[ricktas]

Agree with Mark, that it could be lens flare caused by the brightness of the sun on the snow. Did you have a filter on the camera (UV etc). Sometimes what can happen is that light hits the front element of the lens, is reflected, and then bounces back off the inside of the filter and refracts around inside the lens. Some lenses are more prone to it that others, some also do not need a filter to have lens flare.

[etherial]

Snow, you said it happened with two lenses (which are very different focal lengths), which indicated to me that it was likely a body issue. Was the pattern the same with each one?

[MarkChap]

Didn't think about the filter, but yes I would hazard a guess that there was a UV filter in play here

[SnowA]

Thank you for all your suggestions.

Yes, it was two lenses. Here's one from the 17-55, taken about 40 minutes earlier.



As you can see, the 2nd shot from the 17-55 is with the sun high-ish on my left. The first shot from the 70-200 was with the sun high on my right.

There were (Canon) lens hoods on both lenses. I had a UV filter on the 17-55, but nothing on the 70-200.

I forgot to say this before, but these are all straight out of the camera - conversion from RAW to jpg only in Canon's DPP software.

[SnowA]

Google leads me to possible (early) shutter failure

http://photo.net/canon-eos-digital-c...00LS88?start=0
http://www.birdforum.net/showthread.php?t=78451

Interestingly I don't often shoot at higher shutter speeds (the ones above were 1/1250th and 1/1000th respectively), so I checked for a lower speed one. This was taken early that morning, at 1/400th.



Seems to fit the description. Drat. I recently spent a packet too getting some other bits fixed.

I might have to bite the bullet and make a decision about the 7D/5D II

[RaoulIsidro]

The two images show the bow at exactly the same position.
Perhaps you can run a check on your your sensor for hair.
Cheers!

[ricktas]

other option is a 'snow dog', which is a natural occurance that you may not have noticed visually, but the sensor picked up.

[SnowA]

A snow dog? I'm unhappily all too familiar with snow snakes but not snow dogs.

[mikew09]

Have you cleaned your sensor recently for dust. My freind had a very similiar experience after cleaning his sensor with a sensor brush. After cleaning he had a similiar thing but only showed up on certain shots, aperture etc.
Turned out the brush had removed the dust but smeared some camera lubricant over the sensor. Much like dust bunnies, only showed up on certain setting.

Do a test for dust bunnies and see if it appears then.

[SnowA]

Haven't cleaned it for a couple of months at least. Will give that a go Mike, thanks.

[ricktas]

A snow dog is a meteorological even caused by the sun on bright snow, it is therefore more prevelant in the northern hemisphere (more snow). It causes the effect you have seen here, and is sometimes visible to the naked eye and looks like a white rainbow.

[SnowA]

Just an update. Took it to the Canon service centre yesterday and the techs have confirmed some kind of shutter failure, from wear and tear.

This body has had less than 40,000 actuations and even though it is out of warranty Canon have very reasonably offered to replace the shutter for a fraction of the normal repair cost, as a gesture of goodwill.

Not surprisingly I am very pleased with their response; it is a strong incentive to stay brand loyal. Credit where it's due - well done Canon Australia