PL Mount VS EF Mount

[Haitham Lawati]

Now that Canon is knocking doors of Hollywood in order to step into the world of film production with its newly produced camera EOS C300, the inquiry arises from beginners - like me - about the key differences between PL mount and EF mount in several aspects. Can you please post a reasonable comparison between PL and EF?

[Brian Drysdale]

Introduced by Arri, the PL mount is probably the main mount used on 35mm & Super 16 film cameras. It's use has been carried over onto professional single sensor digital cameras,enabling them to use the full range of cine lenses, which have a number of advantages when shooting motion pictures. This mount is extremely robust and and can withstand the rigours of film making using lenses which are usually heaver (especially the zoom lenses) than stills photography lenses.

The EF is a Canon mount introduced for use on their SLR cameras, which has the connections to allow for automatic focus using motors built into the lens. Mechanically, I gather the lens isn't as locked in place quite as securely in the EF compared to the PL, which has a pin that prevent a twisting movement in the mount.

The PL mount is available with i data connections, but these aren't used for focus control, but for recording lens data like focus setting etc for use in post production. PL mount lenses are manually focused, they don't use automatic focus.

The flange focal distances are different: 44 mm for the EF and 52mm for the PL.

[Tim Le]

Head on over to the Cinema EOS FAQ and scroll down to the Lens Questions section: Canon DLC: Cinema EOS Frequently Asked Questions

There's a lot of useful info there. But basically:

PL mount:
- Natively mount Canon PL lenses and most third party PL lenses.
- PL stands for positive lock. There's a ring that locks the lens into place, making a very solid connection.
- The PL mount actually allows the lens to be oriented in any of four different configurations.
- The C300's PL mount does not have any electrical contacts at all. So no lens metadata will be transferred to the camera.

EF mount:
- Natively mount Canon EF and EF-S lenses (some EF-S may vignette)
- Provides power for Canon in lens image stabilization
- Can control aperture on the camera body
- Focus can be controlled via Wi-Fi adapter
- With most EF and EF-S lenses, the camera can do peripheral illumination correction
- EF mount is a bayonet mount and was designed for still photography. The lens only mounts one way and is captured, but it's not a positive lock. The lens can have a small amount of rotational play after mounting.

[Jon Fairhurst]

If you want to shoot primes and there's a rental house with PL lenses available, PL might be the way to go.

One challenge with S35 is that there is a limited selection of fast, wide primes for the EF mount. But if f/2.8 zooms are cool for your wide shots and you want to own your glass - or if there are no PL lenses available to rent - then EF is the way to go.

Of course, if you can afford a collection of PL glass, then the rental thing doesn't matter.

[Chris Medico]

It would make sense to buy the EF version of the camera and use a PL adapter when you wanted to use to cine glass.

I know its not an ideal solution but the most flexible one.

[Haitham Lawati]

Thanks to all members who have responded to my inquiry. Now the only question that come into mind is how do you distinguish between PL and EF in terms of quality, such as image sharpness, colour dynamics, chroma key, etc?
If there are differences in terms of quality - in case- then what makes PL lenses incredibly expensive?

[Brian Drysdale]

The image quality has nothing to do with the actual mount itself.

PL mount lenses range from stills optics that have been fitted in cine style housings, to expensive hand built lenses using the best optics available so that they're very sharp even even the lens is being used wide open. They're also designed so that you don't get breathing (a slight zoom effect) when focusing. The cine zooms need to hold their stops without ramping.

The main difference is the mechanics - the expensive bit - is more complex on the cine lenses that use PL mounts compared to that found stills lenses. This allows expanded focus scales for accuracy when using tape measured focus as used by the 1st camera assist, who pulls the focus during the shoot. It also allows for smooth operation, without stickiness over the working life of the lens, which could be 20 years. Some 1970s lenses are still used, even on the digital cameras like the RED and Alexa. Here's more on the subject: http://matthewduclos.wordpress.com/2...s-cine-lenses/

Here's a link to articles on the main cine lens manufacturers: http://www.dvinfo.net/forum/hd-uhd-2...facturers.html

[Dom Stevenson]

Brian

Fascinating links to the manufacture of lenses i'd never seen before. Many thanks.

[Don Miller]

One advantage a typical "L" EF mount DSLR lens has on an S35 camera like the C300 is that only the "sweet spot" of the lens is used. The corner to corner sharpness is often very comparable to a much more expensive PL mount cine lens.

But of course, as has been pointed out, the mechanics of a true video lens are much more appropriate. The best of both world is to have one or two real video zooms, plus the ability to use the huge variety of DSLR lenses that can be put on EF.

To Tim's list for EF advantages I would add speed. EF has economical fast lenses that are not huge. What does an F1.2 equivalent cost in a cine lens? I have a large variety of EF mountable lenses (Canon, Nikon, and Contax/Zeiss). That choice would be impossibly expensive true cine type lenses.

It would have been better for Canon to handle lens mount like Red. Even if the adapters were expensive.

Will a PL adapter work on a C300 EF mount camera? Without the DSLR mirror it might?

[Brian Drysdale]

How sharp the still f1.2 lenses are compared to the higher end cine lenses may be open to question. Zeiss derated their CP2 lenses max aperture compared to the first series T1.5 because they didn't think they were up to their cine standard when wide open. Also, you usually need a set of lenses at the same max aperture, not just one or two focal lengths. The Canon PL primes do look like they may use the optics from their stills lenses, although how much cherry picking of the better quality glass goes on could be an interesting question.

There are a number of PL prime lens sets now available from various manufacturers if someone wishes to go that route. It really depends how you plan to use the camera and there is the Wi Fi remote for use with the EF lenses if you go that way.

I expect, if it's possible (it looks like it should be), someone will bring out a EF to PL mount adapter, perhaps attaching it in the robust fashion that some companies have done with the higher end FS100 PL adapters,

[Chris Medico]

There are a number of EF to PL mounts in the marketplace right now that are being used to put cine glass on Canon dSLRs.

That is exactly why I made the comment a few posts up that you will get the maximum flexibility with the EF version of the camera.

Since the backfocus distance on PL is the longer of the 2 you can get away with a simple mechanical adapter. It will be harder to put EF glass on the PL camera because of the shorter backfocus distance of the EF lenses.

[Ken Diewert]

You may recall that last week I griped about working an Epic for a week with a big 10 pound PL mount cine lens (Reds 18-85 t2.9). It was so heavy that it really limited our shooting style to sticks and dollies. Well, 2 days ago, the $2,000 EF adapter finally arrived with promised auto focus capabilities. We used a 17-40L f4, and and a 24-70L 2.8. The camera becomes a whole different piece of equipment with the canon mount. In terms of weight and flexibility. However the operator hadn't mastered the Focus Assist features and we had to manually focus the camera on several occasions and trying to pull focus on an EF lens without a properly geared follow set-up is not easy. The witness marks are far too delicate.

[Brian Drysdale]

Originally Posted by Chris Medico

There are a number of EF to PL mounts in the marketplace right now that are being used to put cine glass on Canon dSLRs.

That is exactly why I made the comment a few posts up that you will get the maximum flexibility with the EF version of the camera.

Yes, just to give an example of one I found with a google... There are others.

Matthias Uhlig lebt…| PL-Mount adaptor for Canon EOS 7 D

I'd want to make sure the PL adapter is robustly secured to the camera body if you were going to mount one of those cine zoom lenses.

[Charles Papert]

One multi-purpose solution to "gearing" EF lenses for cine production is a remote focus unit. I haven't had the chance to see a REDMOTE in action so I can't comment on how well that works, but universal units such as made by Preston, Bartech, Hocus Focus and various other international brands (Scorpio, Genio etc) not only allow one to pull focus physically separated from the camera, they will also increase the rotation of a still lens focus barrel comparably to a cine lens (i.e. 300-340 degrees of rotation of the knob). In addition, if a lens with mechanical stops is used such as the Zeiss ZE/ZF's, it is possible with the better digital systems to make up dedicated rings for each lens with the expanded focus scale seen on cine lenses (requires somewhat laborious physical taping out of each mark to a focus chart, hopefully a one-time setup). Some units such as the Preston HU3 have a lens mapping feature that require only six marks and it interpolates the rest, then stores the info in memory assigned to a given lens.

This is a little complicated--I should make a video!--but the bottom line is that with these systems it is possible to simulate the gearing and expanded focus scales of cine lenses with still lenses. It's less effective with focus-by-wire lenses such as the Canons, as you have to manual create limits every time you change lenses (to keep it from eternally rotating) and thus it is impossible to create a focus scale on the knob, but at least you have the expanded rotation still going for you. Also, non-parfocal zooms, even if they have mechanical stops, will create an issue as the witness mark "floats" depending on the focal length the lens is set to.

And of course, you have the tremendous advantage of remote focus pulling, which is invaluable for Steadicam and jib work and can be a major asset for all types of shooting as long as a camera assistant is available. Even a lesser skilled AC who needs to work off a monitor to ensure critical focus will do well if he is able to stand over by a 17 or 24" director's monitor vs a 7" onboard. In a pinch, you can rig the hand unit off the rods so you could pull your own focus with all of the benefits of the expanded range (haven't seen it done, but it's possible).

[Chris Medico]

I'm working on a wireless setup now for my F3. I have the wireless video link working with an Asus WiCast HDMI system. I've been looking for the right wireless FF system for EOS lenses to mount to the F3.

With that I'll be able to have an AC controlling the lens even in a steadicam or jib situation in a much more affordable and lighter package than the normal pro rigs for lens control.