A little interlude from the DSLR Guide, but fear not - new articles will be appearing soon.

 

A couple of weeks ago, I someone asked me a question about how to achieve shallow depth of field on their digital compact camera.  They’d seen the lovely creamy out of focus backgrounds in other people’s shots and wanted to get the same effect, but were finding it very difficult, even with the aperture wide open and the subject a long way from the background.

 

Before I start to explain this, let me state for the record that I have nothing against compact cameras.  Before I owned a DSLR, I had a Nikon Coolpix 880 and a Canon G3, both of which I really enjoyed using.  They were light, compact and easy to use but looking back, shallow depth of field was one of their major shortcomings.  Take a look at this example.

 

 

On the left - Nikon D200 DSLR with Sigma 105mm Macro

On the right - Canon G3 Compact in Macro mode

 

Both shot with an aperture of f/3.5 (the widest aperture available for direct comparison).  The focus point on both images was the word ‘things’ in the first line.  You’ll notice that the DSLR shot on the left has sharp focus on that first line, then within a centimetre if starts to create the great blurry look associated with shallow depth of field.  

 

The compact shot on the right, however, is almost completely sharp throughout.  

 

Why is this the case when both shots were taken at the same aperture?  Because a compact’s lens is not directly comparable to an SLR’s lens, so the apertures aren’t directly comparable either.  In my tests, the compact’s rendition of f/3.5 was roughly equivalent to f/11 on the DSLR.    If you’d like the more technical explanation, take a look at p46 of Bryan Peterson’s book  ‘Understanding Exposure’

 

Unfortunately this is the reality of trying to achieve shallow depth of field with a compact camera - it’s just never going to be as good as a dedicated lens.  

 

But on the up side, if you’re shooting landscapes you have a huge advantage because of that greater depth of field.  Virtually everything in sight is going to be in focus!