Thank you for the replies. Here is my compiled understanding of the factors that do, or at least probably do, contribute to much higher prices for cine lenses compared to still lenses.
- Uniform size
- Manual iris
- Number of iris/aperature blades
- Geared iris rings
- Continuous (or declicked) iris control
- Calibrated T-stop marks that account for light loss through the lens elements
- Geared focus rings
- Detailed calibrated focus marks
- Elimination of focus breathing
- Glass is optimized for cine circle of focus
- Minimization of distortion of field of view
- Economics of market (production scale, market size, price sensitivity of demand)
I might have missed some important or subtle reasons here, so feel free to add to the list.
These make a lot of sense. In some cases, I should have thought of them. For example, the breathing issue has bitten me in video that I've shot with my DSLRs. I'm no pro, so most issues aren't things that I would have run into, but I can see how important and valuable they would be in a production. I would classify nearly all of these as mechanical and not necessarily things that are related to superior optics (excepting, perhaps, the circle of focus, distortion, and breathing). But, I think I had been way too hasty to dismiss mechanical issues as trivial to both the cost and the resulting moving picture image. They are not. I can see how valuable they would be.
Thanks again for the education!