35mm format lenses in 16mm

[Jarin Blaschke]

When shooting super 16, will a 16mm format lens perform better than a 35mm lens? It never crossed my mind before - I've always used 35mm lenses when shooting 16 in order to get a better array of focal lengths (I love 35mm and 65mm focal lengths in the format for example), but last year I had a super16mm film (shot with superspeeds) blown up to 35 and it was much softer than another film I had seen at the festival blown up, shot with a zoom lens. Previously I had only finished on video and any softness of the image was not nearly as apparent. I also shoot very open - usually around a t2 to get less depth of field in 16mm. I'm sure that didn't really help either. Anyway, I figure lenses designed for 16mm can attain better resolution for that format since they don't have to cover as much film and can get glass closer to the film plane - like a medium format lens can technically atrender more lines per millimeter than a large format lens when shooting still photography - but it's image is enlarged more so this difference is negligable. Is this an accurate assumption? If so, is this enough of a resolution difference to become noticeable? I'd like to pin down why the film was so soft. Thanks.

 

 

-Jarin

[Mitch Gross]

In theory you are correct. A lens designed to cover Super-16 only doesn't have to work as hard as a lens that must cover 35. But that's only in theory. In practice the lens design companies spend far more attention and money on designing 35mm format lenses, so the 16mm ones are not as current in technology. THe only place where this is different is in HD primes, which are designed to cover a 2/3" sensor that's actually just a bit smaller than the S-16 image area. Soon enough some of these designs will be incorporated into new Super-16 lens sets (the Zeiss DigiPrimes will likely be the first). But until then the centerline resolution capabilities of the 35 lenses are about on par with the best 16mm lenses if not superior.

 

Why your film was soft is open to so many reasons. Perhaps your gate depth was off, or your lens mount. The optical printer may not have had inferior lenses or have not be set correctly. Perhaps you went through IP/IN stages while the other prints were direct blow-ups. There's many reasons why one blowup could look softer than another. Maybe your 35mm lenses were out of collimation.

 

It's very easy to see how well a lens performs, at least in terms of resolution. Any decent rental house will have a lens projector in the back. Stick a lens on, turn off the lights and look to see how sharply it resolves at the center and the corners. I've compared lenses and been astonished at how off they can be sometimes.