Lens Choices for the PMW-F3

[alisterchapman]

The PMW-F3 has two lens mounts out of the box. The PL mount (via a supplied adapter) and the new F mount. PL mount lenses were developed by Arriflex for use with movie cameras, so PL mount lenses are an obvious choice. You used to be able to pick up older PL mount lenses quite cheaply, but when RED came along most of these got snapped up, so now PL mount lenses tend to be expensive. Sony will be producing a low cost three lens kit comprising of 35mm, 50mm and 85mm lightweight PL mount lenses. If you want top quality then Zeiss or Cooke lenses are the obvious choice. If your budget won’t stretch that far there are a number of 35mm SLR lenses that have been converted to PL mount.
PL mount lenses often have witness marks for focus. This are factory engraved markings, individual to that lens for exact focus distances. They also often feature T stops instead of F stops for aperture. An F stop is the ratio of the iris opening to the focal length of the lens and gives the theoretical amount of light that will pass through the lens if it was 100% efficient. A T stop on the other hand is the actual amount of light passing through the lens taking into account aperture size and transmission losses through the lens. A prime lens with an f1.4 aperture may only be a T2 lens after loss through the glass elements is taken into account. A multi element zoom lens will have higher losses, so a f2.8 lens may have a T stop of T4. However it is the iris size and thus the f stop that determines the Depth of Field.
But what about the F mount on the F3. What will that let you use? well right now there are no F mount lenses, but Sony are planning on a motorised zoom for next year. I am expecting a range of F mount to DSLR mount adapters to become available when the camera is released. These adapters will allow you to use DSLR lenses. The best mount IMHO is the Nikon mount. Why? Well most modern DSLR lenses don’t have iris controls. The iris is controlled by the camera. Nikon are the only manufacturer that has kept manual control of the iris on the lens body. When choosing a lens you want to look for fast lenses, f2.8 or faster (f1.8, f1.4) to allow you to get shallow Depth of Field. You want a lens designed for a full frame 35mm sensor to avoid problems with vignetting or light loss in the corners of the image. You want a large manual focus ring to make focus control easy. Prime lenses (non zoom) with their simpler design with fewer lens elements normally produce the best results, but a zoom might be handy for it’s quick focal length changes. Do be aware however that zooms designed for stills photography normally don’t hold constant focus through the zoom range like a video lens so you may need to re-focus as you zoom. I have a nice Mk1 Tokina 28 to 70mm f2.6 Pro zoom. The optics in this lens are based on the Angineux 28 to 70mm and it’s a great all round lens. I also have a Nikkor 50mm f1.8, Pentax 58mm f1.4 and a few others. Of course you can also hire in lenses (DSLR and PL) as you need them.