STEPBYSTEP / Capture a sea change

1 Think slow and steady

Set up on a tripod and focus before switching to manual focus to lock it. Before attaching the ND filter, take atest shot. Use Aperture Priority and ISO100 with an aperture of f/11 or more. If it looks good, take note of the shutter speed, which was 1/60 sec at f/11 in our test shot.

2 Attach the filter

You won’t be able to see once the filter is on, so make any final composition tweaks then attach your ND filter to the lens. We used Formatt-Hitech’s Firecrest filter holder with a 13-stop ND. Next block up the viewfinder with a cover or a piece of tape and turn off VR or stabilisation.

3 Do the maths

The shutter speed in our test shot here was 1/60 sec, so with the 13-stop ND filter attached we need to double this value 13 times, equalling 2 minutes 17 seconds. There are apps such as PhotoPills (see page 16) that have exposure calculators to work out the exposure time for you.

4 Time the exposure

Switch to Manual and lower the shutter speed to Bulb. Attach a remote release and lock open the shutter for the required time – or use Triggertrap Mobile (see page 16), which uses a dongle to connect your camera and phone, and an app that enables you to specify exposure time.

5 Convert to mono

Long exposures often have more noise, so use a noise reduction tool such as Adobe Camera Raw’s Detail panel. Then convert the image to black and white and use Camera Raw’s HSL/Grayscale panel to control the brightness of colour ranges – we darkened the blues.

6 Lighten and darken

Often brightening water and darkening skies changes the mood of your image. In Photoshop, Shift-click over the sea with the Magic Wand to select it, then add a Levels Adjustment layer and use the sliders to lighten it. Repeat this method to adjust other areas of the image.