How do you get that background blur?

Here's something for you SX40'ers to think about.

It can be really confusing when it comes to Aperture because our SX40 doesn't respond quite how an SLR will to changing Aperture.

When you change the aperture of an SLR lens, it essentially widens the hole that light passes through when you use a low number like f2.7. This allows more light to pass in and therefore helps us take pictures in lower light conditions.

HOWEVER, there is another aspect of our picture that is affected by this. In the SX40 it is incredibly subtle, whereas an SLR responds very strongly to it and it is the amount of blur aperture controls.

When all of that light floods in, the focus is on the foreground and the background is blurred out. If the aperture was at a higher value such as f8.0, the light is travelling through a much smaller gap and the focus is more concentrated allowing the background to be more in focus.

So with an SLR, a small aperture number like f2.7 lets in more light and causes more background blur. A higher number like f8.0 lets in less light and causes less background blur.

This is how many pictures are taken where the photographer has blurred out everything but their main focus - they set their aperture to a low number.

A lot of people are asking how to do this on the SX40 and the truth is, it just doesn't respond the same way an SLR lens would and makes that effect a little more out of reach.

Best plan is to use the Bokeh tips. Keep a big distance between you and your subject and another big gap between your subject and it's background. Zoom all the way in and it should throw the background out completely.

You can also try using macro mode and getting up close but that isn't always ideal.

I hope that clears up some peoples questions about background blur.

Just a last note to mention the recent lighting guidelines helpsheet I posted. That is only really ideal for the SX40 because of the issue with the aperture varying between cameras so bear that in mind ;)