When doing a multi-image focus stack for more depth of field on a dragonfly image, I usually set my f/stop to f/11 or f/16 when using a 300mm f/4 lens with a 1.4x teleconverter. This way I do not need as many shots for the full focus series of images. Many times a dragonfly will fly off or change position before I finish the series for a stack so I cannot use it and have to start over. This dragonfly seemed to be very still & cooperative. So I managed to do a focus stack from head to tail, including wingtip to wingtip. This series was 12 images, shot at f/8 for a smooth clean background. For a focus stack with a large number of images, I also use a tripod. After flattening the layered file, you might have a minor touch up here or there.