By site editor Dan Chung:
If you want a PL-mounted cinema zoom for your ARRI, Red, F55 or Varicam then your choices are limited. If you have a spare $70,000, then Canon sell an amazing 50-1000mm Cine Servo zoom. Otherwise you are limited to older adapted stills zooms or B4 superzoom lenses with mount convertors.
Dutch specialists Ekton have created an interesting solution that, while not cheap, is much less than other alternatives. For 1900 Euros they will take a Sigma 150-600mm Sports stills zoom and convert it into a PL-mounted lens with a manual iris.
This is no mean feat. The rear of the lens had to be cut off and then replaced with a custom made PL back end. Being a zoom of this length it doesn’t hold focus throughout the zoom range. Etkon remedy this by adjusting the back focus of the lens to make it as parfocal as possible. Samples of the 150-600mm may vary from sample to sample, but Etkon told us that the initial lens they converted holds perfect focus during zooming.
The original lens has an image stabiliser, but I don’t think this will work after the conversion has been done as there is no way to power it once the electronic mount is removed.
The iris has nicely engraved aperture values and the pictures below show what to expect – although, as you can see, it is yet to be sprayed and to have the engravings painted in.
The lens has its own tripod collar and foot, but Etkon recommend this is removed and replaced with a custom lens ring that they can supply.
The conversion takes around two weeks from when the lens is booked in. For more details contact Edwin Schouten at Etkon.