Originally posted by langone_peter I have just sold my Ai'd Nikkor-Q.C Auto 135mm f2.8 with the thinking to replace it with a 'newer' 135mm lens. I can pick up either the f3.5 Ai-s or the f2.8 Ai for the same price. The f2.8 ,cosmetically, is a bit shot, while the f3.5 looks great. In terms of IQ, sharpness, colour, contrast - which would be the better lens?
Regards,
Peter Langone From what I recall the f2.8 is a 5:4 design and the f3.5 a 4:3 design. The f2.8 is a quite similar design to the design Pentax used for many 135mm's from the Super Takumar 135/3.5 over the Takumar bayonet to the A135/2.8, but the third lens is replaced by a cemented doublet. That should make it perform better. I would guess however that it is not up to pair with the more expensive Pentax designs. The f3.5 is simpler than the SMC Pentax-M 135. But that is on paper. I used the Nikkor 135/2.8 when I served as a photographer in the Swedish air force some 20 years ago, and recall it as a good performer. I've never used the f3.5, but heard it is sharper than the f2.8. Try google them. There should be reviews out there. BTW, you know you can mount many Nikon lenses on Pentax cameras, right? The pre-AI even lock, but the others you have to be a little bit carefull with. Put them on upside down.