A 2/3" CCTV lens on the G1

[RichA]

Pentax Cosmicar 25mm f1.4 2/3" CCTV lens. Vignetting is definitely worse than a 1" lens, but there isn't the hard circle vignetting of the shorter lenses in 1" format (e.g., 16mm) or smaller.

 

[raydeng]

My friend got an unbranded CCTV lens made for 2/3'' format here in China for less than $20. I find that it's really interesting and I may decide to purchase one. The characteristics are a little baffling: very very sharp center performance, very swirly bokeh (why would you spend 1000s on the Cookes?), and a very soft vignetting wide open.

The only thing is this: the vignetting hardens up as you stop down. Is that the case with yours?

 

[RichA]

My friend got an unbranded CCTV lens made for 2/3'' format here in China for less than $20. I find that it's really interesting and I may decide to purchase one. The characteristics are a little baffling: very very sharp center performance, very swirly bokeh (why would you spend 1000s on the Cookes?), and a very soft vignetting wide open.

The only thing is this: the vignetting hardens up as you stop down. Is that the case with yours?

Yes, but there is less of it stopped down (it's confined to the very corners) and it doesn't impinge into the image body as much which also means less distortion of the image edges.