5.3. Technology and photographic considerations
1. A high-resolution camera (3648 x 2736, 10 megapixels, or higher) is preferred. We recommend a DSLR or similar camera. Compact cameras will work fine too, but it is unlikely that eggs and young brood will be visible.
2. Use image formats with the least amount of compression (resulting in the larger file size). For DSLR cameras this will be either RAW or TIFF format, and for compact cameras JPEG. As Image J software doesn’t support the use of RAW images, conversion to either TIFF or JPEG files (uncompressed) is required. This can be done using free-ware such as Irfan-View (http://www.irfanview.com/).
3. Use of a tripod with a fixed distance to the frames is recommended. This makes image analysis easier and pictures more comparable.
4. Make sure the object (frame) completely covers the picture. This will result in the highest resolution and optimal lighting conditions.
5. It is advisable to use Shutter speed priority (indicated with an “S” on camera) with a setting of 1/125. Lower shutter speeds can result in blurred bees as their movement is caught on camera. In low light conditions use a flash or adjust ISO values.
6. Aperture settings are dependent on the type of lens used. For DSLR we suggest using a fixed 50 mm lens. These generally are affordable, sharp, fast (low f-value, e.g. f1:1.4), and have little distortion. Using these lenses the f-value should be above f4.5 for sharp pictures. For zoom lenses aim at an f-value of between f6.7 and f13.
7. Cloudy conditions can create low light levels, likewise the sun can obscure details due to high contrasts. Optimal results are possible with a shaded location and a flash, but in our experience this is not practical due to terrain difficulties and limited battery life. Cloudy weather is no problem when using a fast lens. When it is sunny, it is best to take pictures with one’s back to the sun.