Basically, there are four types of image blur:
- Focus blur: Camera focus was set incorrectly or was changed accidentally while capturing. Focus blur can also occur when using low aperture values (e.g. F2.8 or less) which result in a reduced depth of field. When capturing a tower, it is important that both the tower itself and the distant background are sharp.
- Motion blur: Images were captured in dark conditions (dim weather, very dark clouds, etc.) or using a high aperture (e.g. F11), resulting in slow shutter speeds.
- Lens diffraction: High aperture settings (e.g. F8 and above) cause diffraction blur and loss of contrast.
- Image noise: Loss of sharpness due to image noise occurs when using high ISO settings of typically ISO 400 and above. The best results are obtained with ISO 100 or lower. Even at ISO 200, some drones suffer from increased image noise.
SiteSee captures require the following ISO and aperture settings: ISO 100, F4. These settings will produce images with low noise, no diffraction issues and sufficient depth of field (provided focus was adjusted correctly as explained in our capture guides). In good weather, this ISO/aperture combination will typically result in shutter speeds between 1/500 to 1/1600 second, which is more than fast enough to avoid motion blur.
In summary, if possible use ISO 100, F4 and a shutter speed faster than 1/500 second. If you don't have enough light to do so, the preference would be to fly on another day with brighter weather. If you must fly in dim conditions, you may reduce the shutter speed further to a minimum of 1/250 second and, as a second step, increase ISO to ISO 200. Depending on your drone model, using ISO 200 might, however, result in slightly reduced resolution.
Our capture guides for Scanlink and Mission Planner outline easy step-by-step procedures for setting focus and exposure reliably. Please adhere to these procedures strictly.