It has a bright f/1.7 aperture and is capable of sharp rendering. - Model Name: smc PENTAX-M 1:1.7 50mm - Country of Manufacture: Japan - Aperture Range: f/2.8 - f/22 Thank you for viewing. Operation has not been confirmed. Please take a look at the photos and only purchase if you understand. We will consider price negotiations. Please feel free to contact us.