Voigtlander Prominent

[louis]

I collect cameras as well as take pictures with them. I noticed that the 50mm f1.5 Nokton on my Prominent has 14 blades on the aperture diaphragm.

The 50mm f1.4 on my OM1n has 8.

The 50mm f1.4 on my Nikon has 7.

What practical difference does this make other than giving you more perfectly circular apertures? I assume none, since Nikon equipment is always favored by Pros and Pros usually buy the best equipment.

 

[Sonnar Brian]

"Auto-Aperture" (ie not preset or manual) ,SLR's have fewer blades so that they can close-down rapidly. I have a Tessar in 42mm screw mount with lots of blades, nice circular aperture. It is a preset.

The idea is to give round highlights in the out-of-focus regions. Or you could just shoot wide-open.