Tilt/Shift vs Focus Stacking

An early mentor of ours had a saying “If your photos aren’t interesting enough, you aren’t close enough” and I tend to agree.

Much as I’m a fan of “negative space” foregrounds, I’m also keen on the impact of a JCB (Joe Cornish boulder) foreground, but that then gives me a problem with depth of field, if you have a subject very close to the camera. Even when using a wide angle lens at f22, you still struggle to get front to back sharpness.

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Looking at the example of the frosty morning at Costa beck, the image has considerable compositional merit, but is technically flawed owing to using an aperture as small as f22 giving me the problem of “diffraction softening”. So how do we get around it?

Winter Morning, Costa Beck

Focussing at the hyperfocal distance helps, but you will still struggle to get the image pin sharp from front to back, particularly if you have detail very close to the lens. Standing back a bit, then cropping the image later also helps, but there has to be a better way. Fortunately there are alternatives such as a tilt/shift lens which can be used to great effect to give you front to back sharpness. I have to admit that I have been tempted, but as with most good ideas it also has some negatives, not least the cost as it’s expensive at around £1500.00. They are also heavy and I’m loathe to add yet more weight to my backpack plus I’m also not keen on continually changing lenses in the field for fear of getting dust on the sensor.

So what other alternatives are there? Well one that seems to be gaining popularity is “focus stacking”. Essentially taking multiple shots with varying focus points and blending them. Sounds good to me and avoids all the cost etc. associated with the tilt shift lens.

I started doing some test shots and read an article in a photo magazine as well also doing some research on the internet. The article was written by a photographer I much admire, but the explanation was as clear as mud and ended just before it got interesting. I also spent a long and tedious evening reading articles on the internet and found plenty of technical guff, but very few gave any layman’s quick guides to how to do it in the field. However I did manage to glean enough information to make it possible to shoot the type of shots I’m after. Basically you are trying to get enough depth of field overlap to ensure that all of your final image is in focus.

In my first test on the daffodils, I took one frame focussed on the foreground and another focussing on the temple in the background, but once blended I got areas in the middle that are falling out of focus, so the whole image looks odd.

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In reality you need to take more shots to overlap the in focus areas. So how do you do it in practise? You could make some complex calculations, but it would probably be raining by the time I’d done them! You can even get an app for your I-phone that calculates the overlap for you, but it is still quite a laborious task and I’m one of the few people in the world that don’t have an I-phone. What I’m looking for is a laymen’s rule of thumb I can quickly apply in the field.

Reading between the lines on the internet and using daffodil shot as an example.

  • Frame 1, focus on the nearest object ie the first bunch of dafodils.
  • Frame 2, focus at the hyperfocal point
  • Frame 3, focus on the dafs in the mid ground
  • Frame 4, focus on the temple.

Using the poppy shot as another example, similar steps to the above but you are looking for distinct areas that need to be kept in focus, so you may need to add frames to get sharpness throughout.

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Some of this is conjecture and only time will tell if this approach will be successful, but it does look promising so far.

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