Important notice about lens selection

[Jason Rodriguez]

Hello,

We've been doing some internal lens testing, and have found that a number of 16mm lenses *do not* cover the sensor and instead vingette where you see the edges of the image circle that the lens is casting on the sensor.

If you're looking at 16mm c-mounts or other cheaper lens alternatives, make sure that the lens can fully cover an 11.5mm diameter image circle with no vingetting.

From what we've tested, Super-16mm lenses fit this criteria, and the 2/3" certified c-mount lenses from Fujinon fit this criteria. We are not sure about a number of the discontinued third-party used 16mm lenses on the market that users on this board have been speculating about purchasing since we don't have any in-house.

So again, make sure any lens you purchase can fully cover an 11.5mm diameter circle without seeing the image circle of the lens.

According to the technical specifications of the 16mm camera aperture, the 11.5mm diameter should be do-able by a 16mm lenses (so you would not need a Super-16mm lens), but it seems that in practice, this can actually vary quite a bit, or be so close to the edge that you start to see the image circle. So while I still think 16mm lenses are usable based on the format's technical specifications, the best thing for you to-do is test or check before you purchase rather than assume when it comes to older lenses, especially the c-mount bolex class, or anything that was a b-mount conversion, etc. Either that or make sure you have some sort of money-back guarantee.

[Steve Nordhauser]

Just to be a bit more precise, the SI-2K sensor is 2048 x 1152 with 5 micron pitch pixels. The diagonal measurement is 11.75mm.
-Steve

[Jason Rodriguez]

Thanks Steve :) . . . too bad I can't go back and edit!