Auto Focus - GigaPan Epic Pro User Manual

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Setting up the GigaPan EPIC

Auto Focus

There are situations when auto focus is a better choice, than manual focus for
increasing the sharpness of a panorama. One example is a crowd of people or a
building that are at an angle and span a large distance. You will not be able to increase
the depth of field to cover the entire distance, especially if you are using a longer focal
length. You can use autofocus to shift the center of focus closer or farther for each
position in the panorama if you have a suitable situation for autofocus. There are
advantages and difficulties with each method depending upon the particular situation.
The 'Shutter length' setting in the 'Expert options' and using a faster lens with a
minimum aperture value such as f/2.8 versus f/5.6 are two ways to make autofocus
work better. Another important hardware consideration is the autofocus system of the
particular camera body that you are using.
Potential subject problems
Multiple objects at different distances - may need to reduce focus points used or
temporarily switch to manual focus for that region of the panorama.
Areas devoid of discernable features - need to use manual focus for entire or part of
panorama. There needs to be discernable features where the camera body focus
points are located.
Moving objects - May need to repeat particular photograph or pause panorama
Enough light - May need to use better equipment such as a faster lens such as f/2.8
versus f5.6. May need to use manual focus
Important auto focus camera settings include:
1. A faster lens with a lower minimum aperture value such as f2.8 versus f5.6. The
aperture value is inversely proportional to the diaphragm diameter. A wider opening
allows more light to hit the autofocus sensor.
2. A focus policy where a photograph is taken only if good focus is achieved versus a
release policy where the photograph will be taken regardless of whether good focus
has been achieved. Increase the 'Shutter Length' setting to increase the amount of
time that the focus signal is asserted.
3. The auto focus mode such as single servo, continuous servo, or mixed.
4. The focus points that are selected.
With Canon DSLR cameras the auto focus mode is tied to the release or focus policy.
Nikon cameras have a default release priority or focus priority which may be changed
using the camera menu system.
You can use a combination of auto focus and manual focus in difficult lighting
situations, such as blue sky, smooth water, or bright lights.