The Sony FS-7 and now FS-7 Mk II are amongst the most popular mid-range 4K cameras around today and whilst they are compatible with either EF mount or PL mount lenses with suitable adapters, the FS7 series cameras are fitted with a native lens mount E mount or APS-C format and it is not commonly known that lenses actually exist which can be fitted directly to these cameras without needing an adapter.
This is a shame, as there are some useful lenses available to the film maker today and this article explores the advantages of using native APS-C or E mount lenses and details the range of lenses available today.
In case you are confused with the naming convention, there is no difference between E Mounts or Sony α Mount and as these are all different names for the same mount. APS-C format represents the image size, which is very comparable to Super-35 and is independent of lens mount, though this is often used with E Mount lenses.
For easy reading, I shall refer to this mount as an E-mount, rather than calling it an E-Mount/APS-C/Sony α Mount.
Why does the E-format exist?
Without going into the boring bits about image sensor compatibilities and available space to sensor to permit multiple lens options etc, the important thing here to note is that:
– Native EF mount cameras are NOT compatible with PL adapters (C300, 5D, Blackmagic), – The native E mount cameras (Sony FS7, A7S Mk II etc) are compatible with both EF and PL adapters to allow both EF mount and PL lenses to be used. This is a great advantage, since there are an enormous range of EF and PL lenses available today, all of which are compatible to use giving a huge choice to choose from.
The Canon C300 Mk II and ARRI Alexa Mini/Amira get around this limitation by making the camera lens mount interchangeable to give the user a choice of either a native PL or EF mount but changing the lens mount does involve some unscrewing and refitting and also exposes the sensor. This is not for everybody and certainly not something that you want to do in the field.
In contrast to this, the original Canon C300 Mk I did not have interchangeable lens mounts, so you had to choose whether to buy a native PL or native EF version depending on the lenses that you planned to use.
The Panasonic EVA 1, Canon 5D series cameras, Canon ME20 super low light camera and many Black Magic cameras others ONLY make cameras with a native EF mount.
Seen in this light, an E mount is actually quite versatile.Using Lens Adapters – PL and EF lenses with FS7
With an E-mount camera like the Sony FS7, using a PL adapter does not pose any problems, since all PL lenses are manual lenses by design (the /i data is not compatible with adapters) and the adapter is simply metalwork.
However, using EF lenses with an E-mount camera can be less responsive. Since the majority of EF lenses are electronic and often are devoid of an iris ring (iris control is controlled via the camera body on EF cameras), so users have little option but to use the now-familiar Metabones series lens adapters. These work well and allow EF lenses to be fitted to E mount camera and the user is able to manually ride the iris (or control the iris from the camera) but users frequently claim that iris control is not as responsive as using manual lenses or cameras with native EF mounts.
Another issue is that using lens adapters introduces inherently more ‘play’ in the lenses, since the lens being used will have 3 x separate mounting points to the camera, rather than just 1 when using a native lens mount.
Native E Mount Lenses
Happily, there is a 3rd option and that is to use lenses with native E-mounts – these fit directly to the camera body avoiding using a lens adapter.
• Avoiding a lens adapter make the camera system shorter
• Ensures a solid lens fit without the play introduced when using lens adapters.
• Electronic lens control (where appropriate) is also more responsive, since there is no electronic conversion process which occurs.
Full Frame and S-35 coverage for E-Mount Lenses
One caveat here is worth mentioning – whilst all of these lenses are compatible with FS7 series cameras, A7S series cameras are not compatible with all of them as they have a full-frame sensor.
Essentially, the Sony FS7 and FS7 Mk II have Super-35 coverage, whereas the Sony A7S Mk I and Mk II achieve full frame coverage.
• This means that S-35 lenses won’t make an image large enough to cover the full full-frame sensor if using an A7S MkII, so vignetting will result.
• If you are using the A7S series cameras, be aware that if you are shooting 4K then you will use full-frame and can only use the Sony electronic lenses presently.
• If you are shooting A7 series cameras in HD (not 4K), then you can activate the S-35 windowing (called APS-C mode) and use all of these lenses.
• However, since most shooting is now in 4K mode, this will be a problem. I agree that this is confusing.
Perceived Field of View for Full Frame and S-35
The second issue worth mentioning is that for the Sony compatible lenses, working in Full frame means that the perceived field of view (in full frame mode) is wider than that of S-35, owing to a larger image size being generated by the lens.
The Range of available E-Mount Lenses
VMI stocks 3 x separate types of E Mount lenses: The native Sony SELP/SELZ zooms, the Fujinon MK series zooms and the Veydra Mini primes.
Note that more native E mount lenses are available in the marketplace but VMI currently stock this range of lenses and this is likely to continue to increase as these lenses become more popular.