Depth of frustration

I have been obsessing a little over sharpness recently. While my most used lens is not the sharpest (at the moment that’s the Nikon Z 180mm-600mm f5.6-6.3), I have some obtained some very sharp results with it in good light.

I go on about the challenges of shooting fast moving subjects in poor light blah blah blah, but there are various reasons that make getting pin-sharp results harder.

Having said that, I still want to get the best results I can when the need arises, although many of my favourite shots are far from sharp; but for some wildlife images that is what I am attempting to get to prove to myself that I know how to do it. The example below is well off what I want.

Tīeke, 1/250, f8, 600mm, ISO 500

The shot of the Tīeke was in harsh bright light, the subject was roughly 4 or 5 metres away from me. I was sure I was nailing some keepers, but on getting home most shots:

  • missed the eye repeatedly. To be fair, it was feeding in a tree with a lot of leaves and twigs to interfere, so I was trying to avoid reacquiring focus too often.
  • were exposed poorly. I forgot to change to spot metering.
  • may have been less well defined due to the shutter speed being too slow. Given the light I could have gone up considerably.

But most importantly, I realised that at the maximum aperture of f6.3 at 600mm I had 2mm DoF. I knew I was working on limited DoF with the longer focal lengths, but seeing how shallow it was, was a surprise. Even at f11 at 600mm I would only get 3mm.