I have a friend who'd like to rent some PL mount lenses for a school project (because he's used to work with them and has all the necessary rigs/FF/tripod available at his cinema school (and a budget)). I read what @cbrandin says about film lenses being softer than digital by design, and I was wondering if anyone here had experience with them.
PL mount lenses do not necessarily mean they're film. PL (Positive Lock) is just a type of mount. There are some really high end lenses (Angenieux, Canon etc) for digital cams in PL mount too. But in general yes, the older pre-digital PL cine lenses would be considered softer than modern lenses. It has its pro's and con's, and is a subjective creative choice.
Not all PL lenses are made equal. RED Pro Primes, Zeiss Master Primes, Zeiss Ultra Primes are all sharp as hell. Cooke's are a bit softer, so on and so forth.
There is a major difference. Not sure what the Cons are, IMO, aside from spending more money and having to deal with larger lenses.
I would use them whenever possible. Keep in mind that they are usually quite heavy. If it's a run and gun, no thanks, but if you're really taking time to set up shots... use 'em!
PL mount lenses are NOT always heavy. Zeiss T2.1's weigh as much as the heaviest Zeiss ZE lens. RPP's are heavy, master primes are heavy, but Superspeed Zeiss and a lot of other lenses are not heavy at all. The Zeiss Superspeed S16mm Primes and Zoom are the same weight and nearly the same Size as any SLR lens, the 10-100/2 being as heavy as a 70-200/2.8 SLR zoom.
I use HotRod Adapters, again, see the link I just posted and you can go here to see pics: www.campcomet.com and other info.
Pictured below: Nex5N with Zeiss CP2 (weighs very little, but plenty enough to actually use this setup) and the Gh2 + RPP 18/T1.8, which is heavier.
My major advice: do not get a cheap adapter. You need to support the camera AND the mount, otherwise you're going to be sad when the lens mount tears from the camera and the expensive glass cracks on the ground.
You'll also want to grab a clip on mattebox, totally the way to work with these setups.
@brianluce The best value adapters are from ciecio7 on eBay. Very sturdy, with tripod supports (with 2 mounting holes, too). Never failed me. I think they cost about $300