Too Much Monkey Bidness...The Focus Issue

on June 04, 2015

Did goe to a belly dance show on Monday and was greatley amused - as I always am. The dancers moved like women possessed...mind you at one stage they took 0ne of them away for non-payment of debt. She was a woman re-possessed.*

They move fast, belly dancers - mostly. The tribal ones who follow their leader are very stately in their movements and are easy to capture - the rest are like shooting down kamikazes. Using a camera that has an electronic viewfinder for this sort of shot is problematical - there is a tiny time lag between what is happening and what the finder displays to the eye.

It is a very small time lag, and the makers of the cameras are doing their best to reduce that lag even further. There is also a small time lag in any auto-focus camera while it does the distance measurement by various means and then focuses the lens. Unfortunately these delays can add up and prevent the shutter from going off before the dancer crashes into the front line of seats and bursts into flame.

In an effort to reduce this with the Fujifilm X-system I have selected a camera with a direct optical finder - the X-Pro1 - to eliminate the perception lag. ( Note that the X-pro1 also has a switchable EVF that you can use for precise focusing when time is not critical.)
I experimented with the focus settings and found that the S setting introduced too long a delay as the camera settled into a perfect focus. The C setting sometimes did not get to a point of focus before the shutter went off - and sometimes seemed to pick up the backdrop as the point of focus rather than the dancer.

The M setting was most useful. A little pre-dance experimenting with the centre point of the stage meant that there was a starting point and every time a dancer passed it flailing I could fire instantly.

More experimentation is needed to see just how high the X-Pro1 will synch electronic flash. Conventional wisdom says 1/125 for sure but I suspect I can stretch it up to 1/250 before trouble ensues. The Fujifilm X-100 camera would synch at 1/1000 but I needed a different focal length for this stage.

The too much monkey bidness ( thank you Chuck Berry...) refers to the OS setting on the 18-135 mm lens vs the camera on a monopod vs a shutter speed of 1/30 to gather some of the stage lighting vs a Metz flash firing off the ceiling. Eventually the interconnected calculations and estimations for all this overwhelm the brain and I long for an iPhone...

But it is all good in the end. One day I will get the exact rig working perfectly. Then all I have to fear is a costume malfunction.

Uncle Dick

* Here all week. Try the veal.