Used Cooke S4 primes: what to check before you buy

What to check before you buy

• Glass: front and rear elements free of scratches, fungus, haze and separation. Shine a flashlight through each lens.
• Focus accuracy: checked on a collimator or lens projector, so the marks match true distance and infinity is sharp.
• Rings: focus and iris turn with smooth, even drag and no tight spots or play.
• Iris: blades clean and dry, opening and closing evenly.
• Mount: PL mount undamaged, with flange depth set correctly.
• Lens data: on S4/i lenses, confirm the data reaches your camera or lens control system.
• Set: serial numbers, the same version across the set, and recent service by Cooke or a qualified lens technician.

Questions buyers ask

What is the difference between Cooke S4 and S4/i?

S4/i lenses add Cooke's /i technology: contacts in the mount that send lens data such as focus distance and iris to compatible cameras and recorders. Check which version each lens is, since sets are sometimes mixed.

Do Cooke S4 primes cover full frame?

Cooke S4 primes are designed for Super 35. For large format or full frame, test coverage on your camera at your frame lines, or look at a lens line made for large format.

How do I check a used lens set I cannot see in person?

Ask for photos of each lens with a light behind it, the serial numbers, a recent collimator or projector report if one exists, and a video of the focus and iris rings turning.

Can I add a single S4 lens to a set?

Yes, sets are often built up lens by lens. Check that the new lens matches the set in version and condition.