What’s wrong with this photo ?

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No it’s not that there is a green tinge from the window. Nor is it the toothy grin from Dave.

Have a closer look at the black blobs in the corners.

I was wondering why my photos that afternoon had these black corners. Was my strap hanging over the lens so badly ? super vignetting ?what was going on ?

Only later did I realise that the lens hood was twisted around.

The Canon EF-S 17-55 f/2.8 IS USM lens has a monster hood – mostly to cover the 70mm front end.

I’m still not sold on why I have to cart this monster plastic nose around with me. Apparently it will help stop vignetting and help with better saturated colours. The most convincing reason so far is that if you drop your camera, it will sacrifice itself for your lens. Even though the genuine Canon hood is a hefty $75 or so, it is cheap compared to nice glass like this baby.

Canon Air bags anyone ?

I must be thick, but I only just understood why the hood has 2 big leaves and 2 smaller ones. The reason is that the sensor is rectangular and in `widescreen mode’, and thus the short leaves cover the short ends of the sensor. If you rotate the hood, the long leaves cast a shadow directly over the `film’.

Now I’m off to go read a beginner’s guide to photography.

What’s wrong with this photo ?