Tuesday, June 17, 2014

Stopping down a fast lens to flash sync speed with a neutral density filter

Getting ready for the summer, how can you use flash with a wide aperture under full sun power? You can either use small speedlights at hypersync, which will give very low power, or go down to flash sync speed using a Neutral Density (ND) filter, which is my preferred option.

On location you normally do not have time to do math, so some preparation is useful. Find below a table based on exposure settings at ISO 100, Sunny 16 rule, which you will encounter at the beach, and the corresponding shutter speeds when using ND filters for 3 and 6 stops.

f/stop Sunny 16 ND 3 ND 6
1 1/25600 1/3200 1/400
1.4 1/12800 1/1600 1/200
2 1/6400 1/800 1/100
2.8 1/3200 1/400 1/50
4 1/1600 1/200 1/25
5.6 1/800 1/100 1/13
8 1/400 1/50 1/6
11 1/200 1/25 1/3
16 1/100 1/13 1/2

As you can see, if you have a 2.8 lens, the most reasonable option is to close down to f/4, and use a ND3 filter. If you set the speed to 1/250, you will get a slightly underexposed ambient light.

If you have an f/1.4 lens, you need to use a ND6, to achieve the same result. The ND6 filter is also good if you have an f/2 lens, giving a comfortable 1/100 shutter speed.

So, the settings become quite simple. Measure your flash to give f/16 on your subject. Your camera at 1/250, and f/4 or f/1.4, with ND3 or ND6, respectively, and done.

Another setting I also use quite often is f/11 1/250 on the lens, with a circular polarizer on the lens, that additionally substracts one stop and a half, depending on the filter maker, and gives you those intense skies and pristine waters.

Sunday, June 15, 2014

Sports photography with a tilted lens

Focusing a tilted, manual focus lens fast enough to catch a fast moving target seems to be complicated, right? Couldn't be easier, however.

Since when you tilt the focus plane, things are not in focus based on their distance to the camera, but rather on their position in regards to the frame composition, it's not so difficult to decide which part of the frame you want in focus, and compose accordingly.

In this photo, I wanted to have only the rider head/face in focus, so I arranged the lens to focus the upper third of the frame, and there you go.

Thursday, June 5, 2014

A day in black & white

Man, I love clouds.

I had some time to walk round and take these shots from Oslo. No need to use a b&w conversion filter. I guess my thoughts about cloudy skies could change after spending some time there. All taken with the Voigtlander Nokton Aspherical 35mm f/1.2 II, wide open, on the Sony A7r.