Sony α7s

FoCal can’t control the α7s, so you take the photos yourself and FoCal analyses the files.

1. Set up as for any test

   The test space and camera settings below apply in File Mode too.

2. Take the shots FoCal asks for

   Each test tells you what to shoot. For calibration, that’s a set of shots at different AF Micro Adjustment values.

3. Give FoCal the files

   Copy them to your computer and choose them in FoCal. It reads the settings from the files, analyses them and shows the results.

More in the File Mode help.

1. Choose a solid floor

   Ground-floor rooms vibrate less when people move about or traffic passes, and vibration affects the results.

2. Fix the target to a wall at lens height

   Keep it flat so it can’t move. A FoCal Hard Target is what we use for all our development and testing.

3. Light it well and steadily

   Avoid fluorescent and LED lights, which can flicker in a way you can’t see but the camera can, and changeable daylight. FoCal copes with small changes in light, not big ones.

4. Use a sturdy tripod

   If your tripod has a hook under the centre column, hang something heavy from it. With big lenses, mount the lens’s tripod collar, not the camera.

5. Set the right distance

   The Target Distance Tool in FoCal tells you how far from the target to be, with or without the camera connected.

Target Setup, FoCal’s guided setup, checks the position, light and settings before a test. More in the FoCal help.

1. Charge the battery to at least half

   Low batteries can make tests fail or the camera behave strangely.

2. Take off any battery grip

   Grips add vibration on a tripod.

3. Aim the centre focus point at the target

   Roughly is fine: Target Setup confirms the position.

1. Photo mode

   If the camera has a photo/video switch, set it to Photo.

2. Remove any mode limits

   If the camera lets you limit its options, allow Aperture Priority and Manual, Spot and Matrix/Evaluative metering, and all apertures, shutter speeds and ISO values.

3. Aperture Priority

   Most FoCal tests use it. FoCal asks if a test needs something else.

4. AF-S autofocus

   Set the autofocus mode to AF-S: a half-press of the shutter button locks focus and then stops.

5. A single, centre focus point

   No automatic point selection: you should see one fixed AF point, in the centre.

6. Focus limiter off

   FoCal may use the lens’s whole focus range, so set any focus limiter on the lens to off or the full range.

7. Stabilisation off

   Turn off any stabilisation on the lens: it can make the results less accurate.