Diaphragm (optics) curved blades improve the roundness of the iris opening. In a photograph, the number of blades that the iris diaphragm has can be guessed by counting the number of diffraction spikes converging from a light source or bright reflection. For an odd number of blades, there are twice as many spikes as there are blades. In case of an even number of blades, the two spikes per blade will overlap each other, so the number of spikes visible will be the number of blades in the diaphragm used. This is most apparent in pictures taken in the dark with small
Auckland Flower Show event. Although the organisers planned to follow up with another show, it has not eventuated. Auckland Flower Show The Auckland Flower Show was a flower and garden show held in Alexandra Park in the suburb of Epsom, Auckland in November 2008. Previously, the Ellerslie Flower Show was held at the same time of year in Auckland, and had been held every year since 1994 (except 1997). In November 2007, the organisers sold the name of the Ellerslie Flower Show and the use of their services to the Christchurch City Council, which intends holding future Ellerslie Flower Shows at Hagley Park