Autofocus or Manual
Which is best for your photography and when do you use each option?
Autofocus or Manual Focus?
For most of my work nowadays I make the most of the incredible advances in Canon’s quiet and fast USM autofocus technology. I may be a bit biased here but I do also know that Nikon and Olympus, among others, have similar advancements in their own focussing systems.
Autofocus is so incredibly quick now, its speed has been said to be nearly as fast as the human eye, and is certainly faster than most of us could accurately focus manually! It is great for most subjects, especially as I said before, sports and nature photography.
Manual Focus
There are of course, times when manual focus is not only very handy but also quite necessary:
Still life or studio work
If I am doing a job that has no time constraints and the subject is very unlikely to move, I like to know that I can put the camera on a tripod and lock in the focus manually to give myself one less thing to think about.
Autofocus or Manual - Fig.1
I tend to leave the camera “beep” function on so that I still get assurance that the subject is in focus each time I take a shot. I can then place each object or subject on the same spot each time knowing the focus is taken care of taking into account the depth of field.
Macro Photography
With macro work, you have so little room for error it is sometimes best to rely on your own eyes rather than the cameras. For moving subjects such as insects, it may be worth using autofocus as your time is limited but for stationary objects, take your time and go manual.
Autofocus or Manual - Fig.2
Depth of Field
Remember that with macro work, the depth of field is incredibly small even with small apertures and especially with telephoto lenses such as 100mm or 135mm. Focussing is critical and I would recommend a tripod and manual focus every time.
Sports Photography
This goes slightly against what I have said in the past but there are certain situations, not just in sports photography, where fixing a focus point manually will have great benefits.
For example, if you are doing a rather laborious job and you know that you will be in the same spot shooting subjects at the same distance for a period of time, fix the focus manually on the point of interest so that you can guarantee sharp pictures on every shot (as long as you use a fast enough shutter speed).
To use the same scenario as before, let’s say you are shooting horses on a particular jump at an event. It is a prime position and a difficult jump and you intend to sell the shots to each person as it shows off their skill as a rider.
Once you have found your best position, you could set up the camera on a tripod, manually focus on the jump you intend to shoot, use a small enough aperture with good depth of field to account for any minor fluctuations in movement by you or the rider as you shoot, and just fire away.
By using autofocus in this scenario, it is just possible that the focus may stray to the background as you shoot and you miss the only shot of a rider making that jump…food for thought.
Homework
To get the old “Grey matter” working, think about your style of photography and where autofocus or manual focussing may help you. Go out and practice!