This lens, bought from B&H about two months ago: Pentax C22525KP 1" C Mount 25mm f/1.4 Manual C22525KP B&H This is the perfect starting point for adapted lenses, fast and sharp. Hate to sell it but it gets little use, I basically shoot all the time with my screw mount Takumars. Comes with a good quality eBay c-mount adapter, metal threaded base cap and snap-in front cap. (The lens originally came with cheap plastic ones.) You can see some of my images (and others) here: https://www.mu-43.com/f81/pentax-25mm-f-1-4-cosmicar-c-mount-image-thread-4858/ Asking $100 shipped in Canada or $115 to the US, may consider other destinations. Also willing to trade for a screw mount lens of comparable value. BONUS!!! I forgot I also have a 27mm circular polarizing filter, cost me $25 on eBay. Yours free with this lens.