FS7: FS7 and PL mount - E-mount strong enough?

H

Harry Lime

Well-known member
Has anyone had any experience with using a PL mount adapter on the FS7 E-mount?

Is the native FS7 E-mount strong enough to support a heavy prime (Cooke, Arri Leica etc) via an adapter without causing focus issues due to sag? I've read some chatter on the net that this may be an issue.

Does the PL adapter simply attach to the E-mount or is there additional support? I've see some pictures of a PL adapter that appeared to have a support tongue at 6 o'clock.

Too bad Sony didn't use the FZ mount, like on the F3/F5/F55/F65 but that probably would have cut too much in to F5 sales...

Anyone?

Thanks in advance.
 
I agree you should have support with anything heavy including long DSLR lenses. On the FZ vs E mount - the latter was a selling point for me as it allows me to use image stabilization and speed booster. Both significant tools. You win a little and you lose a little.
 
thanks everyone. Looks like the Wooden Camera setup is the way to go, although it does add $800-900 to the cost of the camera
 
While I didn't actually shoot it, my FS7 was used last week with a PL mount and a Canon 17-120 with lens support. E mount is perfectly intact and unbent.

Ned Soltz
 
nsoltz said:
While I didn't actually shoot it, my FS7 was used last week with a PL mount and a Canon 17-120 with lens support. E mount is perfectly intact and unbent.

Ned Soltz
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I'm talking more of minimal sag that is big enough to throw the focus off. It doesn't take much.

Here is an article by Art Adams (last half)

http://www.dvinfo.net/article/acquisition/sonyxdcam/my-love-hate-relationship-with-the-sony-fs7.html


But it sounds like an additional support bracket solves the problem.
 
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I'm surprised by how many mistakes there are in that article, and I'm not just talking about differences of opinion.

But to get back to the topic at hand, you definately need support for heavy lenses. The mount isn't going to break (probably) but you will have focus issues. I've even seen focus problems that go from the top of the frame to the bottom, as the lens mount sagged and caused the focus to be slightly off on only part of the frame.
 
I had been using Vocas PL mount adapter without support on FS7 for a while now, mostly with lightweight zoom like RED 18-50 or Lomo 25-80 and haven't have a problem, my left hand is constantly there on the lens to control and also give it a bit more support.

if you are thinking of putting modern cine lens like Cooke, Arri Master Prime, or lens heavier than 1kg would definitely suggest using lens support or lens adapter with build in support (VOCAS, Wooden Camera, Solid Camera, Metabone, etc)
 
Yes the emount is just for emount lenses- light and small. I don't think it's a good idea to put adapters on them- especially PL that is a very robust mount in comparison designed for supporting heavy lenses. Without "frankensteining" the camera there always are going to be focus issues with the lenses. Adapters only compound these issues and emount "flex" makes it pretty much impossible to trouble shoot. I suggest to use only emount lenses - they are some great primes and zooms- fast, light, good range, unique features like fast AF, stabilization, etc.
It's a different story about adapters on tiny emount cameras like a7 or a6000: there you're essentially attaching the camera to the (supported) lens. The camera is light enought for the emount to hold steady. As soon as the camera is mounted on the rods and adapters/lenses added the tension in the setup is introduced. And there is no way the operator has the skill or the time to fine tune it. Hence the focus issues are imminent. Add to that the extremely critical 4K focus and no wonder that most stuff shown online has buzzed focus . OK -I get it- it is for CREATIVE reasons hahahaha
 
optitek said:
Yes the emount is just for emount lenses- light and small. I don't think it's a good idea to put adapters on them- especially PL that is a very robust mount in comparison designed for supporting heavy lenses. Without "frankensteining" the camera there always are going to be focus issues with the lenses. Adapters only compound these issues and emount "flex" makes it pretty much impossible to trouble shoot. I suggest to use only emount lenses - they are some great primes and zooms- fast, light, good range, unique features like fast AF, stabilization, etc.
It's a different story about adapters on tiny emount cameras like a7 or a6000: there you're essentially attaching the camera to the (supported) lens. The camera is light enough for the emount to hold steady. As soon as the camera is mounted on the rods and adapters/lenses added the tension in the setup is introduced. And there is no way the operator has the skill or the time to fine tune it. Hence the focus issues are imminent. Add to that the extremely critical 4K focus and no wonder that most stuff shown online has buzzed focus . OK -I get it- it is for CREATIVE reasons hahahaha
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This is the most appropriate post I've read to date on this subject. I come from a career of optical mount design, so, I have a little knowledge of this subject. It's enough to say, here, that every lens glass made, is precision ground to a shape that has to be controlled to a few angstroms of light wavelength. An angstrom is one 10 billionth of a meter. Any variation from the shape introduces distortions, depending on where the variation occurs. The time it takes to grind a lens to near perfection; and, the quality control necessary to measure the results, are one of the biggest drivers to cost of a lens. One reason quality lenses are in the tens of thousands of dollars.

A lens is designed to be perfectly aligned to the focal axis, as well. Any tilt to the lens mechanical axis, relative to the focal plane, will result in coma and chromatic aberration. Point being, if the lens mount flexes to allow tilt, or deforms to shift the focal point, aberration, CA, blur, coma and other errors are introduced in the image. Tilts on the order of angstroms, too small to even detect, are critical. So, you can imagine what kind of image errors are being introduced by mechanical displacements that you can see with your naked eye.

On my FS700, it's very easy to see tilt and shift in the lens, due to machining tolerances and flexing of the lens mount. These all add up cumulatively. We pay the price in theoretical lens performance by the practical limitations to lens engineering. Even a lens support that has been aggressively applied, will force a tilt to the lens worse than the sag from having no lens support. And if you think you can stabilize a lens with your hand on the focus ring, think again.

The e mount is inherently weak because it does not locate the lens mount surface to the camera mount surface in any predictable and repeatable way. One of the best lens mounting designs is shown by the Arri PL mount because it positively locates the lens against the camera body. Sony duplicated this idea with the FZ mount. Too bad they don't follow thru with this mounting concept on their less expensive cams and have devoted so much engineering to e mounts.
 
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moldcad said:
Oh yes - some lens prices can certainly lead to the coma, especially when one cannot rent such a lens and is facing a perspective of purchasing them...
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U get what you pay for.....in the world of optics, anyway. And I find it incredible that some VERY quality optics can be purchased on the used market for such a paltry sum. As the lens diameter goes up, so does the cost of manufacturing. That's why super 35 lenses are so expensive. And maybe that's why there's SUCH a screamin' good deal on super 16 film lenses.
 
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I think the majority of owners of the FS7 and F700 are using those cameras with Canon lenses and Metabones adapters. So far I haven't heard any complaints about focus problems due to misalignment for most smaller lenses but its certainly possible. It certainly does become an issue as the lenses get bigger though. The Canon 17-120 is a monster and also a very desirable lens so its no surprise that Art had issues though he seems to think they straightened out with good support. Some of the other PL zooms are smaller and might be easier to support. My guess is that people will use them until reports of problems come in so keep your ears open and post issues as they come up.

I hear Jacek and Cuervo though and hope that those issues don't show up using EF metabones with smaller lenses.

I was looking into double adapting some of my Nikon lenses to EF adapters and then to EF speed booster in order to limit the number of adapters I was carrying - also because Metabones Nikon adapters don't mate with the Nikon iris properly at wide open . Here I could see obvious flex particular with larger lenses like an 80-200. However the flex that I saw was in the cheap Nikon to EF adapters. ( That's why I bought the Optitek Pro-lock for my F3). I just got a Leitex hard mount adapter that screws into the Nikon lens to change it to a an EF mount to see if that's more stable. Will report.
 
Sony FZ mount is designed for adapters:
Big, strong, locking tightly.
That's why I made adapters for it.
FS7 is a sizeable camera with flimsy spring pressure based mount. That mount was designed for small 1lb or so cameras. It's a perfect mount for DSLR size and weight cameras- especially mirrorless - even lighter.
You combine this mount with sizeable camera like the FS7 and there is focus trouble looming.
Another words:
Small camera+ flimsy pressure based mount = OK
Video sized camera with flimsy pressure based mount- not OK. IMO it's a poor engineering decision from Sony.
But who am I to judge- they sell like hot cakes ;-)))
 
optitek said:
Video sized camera with flimsy pressure based mount- not OK. IMO it's a poor engineering decision from Sony.
But who am I to judge- they sell like hot cakes ;-)))
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LOL....go figure. I'd like to know what the cam side lens mount attaches to in the camera. Is it plastic, or is there a metal subframe in there? A titanium sub-frame might be stiff enough, but, if the lens plate is mounted to plastic, well, enuff said. I have heard of the lens mount plate pulling out if the camera was hit hard enough, or dropped. No chance for repair, that, it is fatal.

I bought one of Sony's first VG20 HD cams. First thing I did was to disassemble the tripod mount. It was absolutely criminal how weak and poorly designed it was. It's the tripod mount for god's sake, and it was held in place by two off center miniscule machine screws. Kinda the beginning of the end of my confidence in Sony engineering.
 
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Lenilenapi said:
I think the majority of owners of the FS7 and F700 are using those cameras with Canon lenses and Metabones adapters.
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Hey Lenny,
yeah, you're right on. every time I mount my Canon EOS 70-200 L glass to a metabones adapter, then hang that off the face of my FS700, I hold my breath. That Metabones adapter hangs all that weigh another 1-1.5 inches out front. yikes.
-Bill
 
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That Canon series II 70-200 is a beast. I tried 3 of them though and noticed that focus shifted every time I reversed the direction of the zoom ring even just nudging it. It is clearly in the design of the lens.That was a deal killer for me So thstarted me thinking what zoom to use instead . My clients love f2 DOF so i need speed booster. Also it enables a wider FOV which is great for interviews in a small room.

The earlier Canon 70-200 is not that sharp and the Sigma and Tamron optics were not well reviewed. (Sigma 50-150 is great but shorter & no speed booster.) That leaves a Nikon 70-200 ( $3K) or my trusty 80-200 which still gets raves for sharpness. Only now I have a Nikon lens. The Nikon metabones adapters are funky . The iris ring on the adapter won't open the lens all the way and I hate the idea of carrying 2 sets of metabones adapters all the time anyway. Hence I am about to try the Leitex Nikon> EF mount on my 80 -200 . ...Jeez! cross my fingers
 
I don't know about other rigs but the tilts rig has an adapter support built in. And every adapter I own (5 of them) has a lens support socket. Within reason it shouldn't be a problem with any but the heaviest cinema lenses.
 
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