FS7: Cinema lens advice for FS7 film shoot
- Thread starter Abaddon
- Start date
Yeah what ever Im trying to say I guess Im not using the right terms then.. but in a camera VF.. a 50mm FF on an APS_C sensor will appear to be a "longer" lens than that 50mm FF on a FF camera.. because the crop 1.5x .. ?? anyway I guess its been done to death
Run&Gun
Veteran
Yeah what ever Im trying to say I guess Im not using the right terms then.. but in a camera VF.. a 50mm FF on an APS_C sensor will appear to be a "longer" lens than that 50mm FF on a FF camera.. because the crop 1.5x .. ?? anyway I guess its been done to death
Because the smaller sensor is seeing less of the image circle. But the magnification(focal length) of the lens itself is unchanged. It’s giving you the same effect as cropping an image in post, but it still doesn’t change the focal length(magnification) of the lens it was shot with. And I guess that’s what a lot of people are trying to get across, the focal length(magnification) doesn’t change. Period. So, a 50mm on s35 might give you the FoV equivalent of shooting 75mm on “FF”, but it’s still not a 75mm lens. Magnification and depth of field will still be that of a 50mm lens.
Forget stills or video, it’s irrelevant for this discussion, because it applies to both. If you have a camera with a s35 sized imager and you put a 50mm lens on it designed for a s35 sized sensor OR a 50mm lens designed for “FF” sensor(no speed booster), the resulting image seen by the camera(sensor) will be exactly the same(same FoV, same magnification). So, whether someone buys a “FF” 50mm lens like the Sigma Cine or Canon CN-E or a s35 50mm lens like a Cooke s4i or Zeiss Master Prime for for their s35 camera, when they put it on the camera the FoV will be exactly the same. Getting a lens designed for s35 doesn’t get you back to the FoV that a “FF” lens gives you on a “FF” sensor.
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Abaddon
Well-known member
Then the question is which lenses you guys prefer, if you've had experience with them. Adorama rentals is probably where I'll go. They have the Canon Cine, Sigma Cine, Zeiss CP2, and various zooms. I think the Sigmas are the only primes that are available with E mount. I have no problem sticking with my Metabones for the other brands if it doesn't negatively effect the image.
Liam Hall
Veteran
Go with the Compact Primes.
morgan_moore
Major Contributor
You have to test with your follow focus. .. if it is motorised one can get shift with bad adapters flexing the lens up and down or round
(every adapter that is not PL is bad)
Ideally you would get a proper PL mount for the FS7 (one that has its own tripod foot or attaches to the top holes)
like this thing from wooden camera https://store-abt.de/product/e-mount-to-pl-mount-pro-fs7/
Run&Gun
Veteran
I own a full set of the Canon CN-E's and really like the image, as do most people who shoot with them and their clients. The only drawbacks are they are native EF* only(although Duclos does a non-destructive conversion to PL. But it's a completely mechanical conversion, so you lose lens data, if that's important to you.) and the aperture ring needs more travel. The throw is kind of short, IMO. The pluses are they make people/skin tones look great, they are sharp, they are "FF" and EF lenses are essentially "universal", meaning you can adapt them to pretty much any camera.
I've only had one Sigma Cine Prime in my hands, but I liked what I saw in the time I had it. It was sharp as you'd ever need(judging on my F55), it seemed to match my Canon's image wise and the build quality was top notch. The Sigma's do have a few quirks that I don't like, like it's a 95mm front instead of 114mm(matte box compatibility, not the end of the world, but something to consider if you have other brands of lenses), they charge you an extra $1,000(!) for luminous markings(may or may not be important to you) and even though they are available in multiple mounts(EF, E, PL, etc.) the conversion cannot be done by the customer and the PL lens is PL ONLY, it cannot be converted to another mount. And not a big deal for me, because I'm not working in a narrative environment with an AC, the focus rotation is "only" 180 degrees compared to a lot of others, like the Canon's that are 300.
*Saw a rumor on Canon Rumors a few weeks ago that Canon is bringing out a set of PL mount primes, themselves. And supposedly they have dialed back the sharpness and contrast.
Abaddon
Well-known member
I've used a Canon CN-E 50 and 85 in the past with my Metabones adapter. I liked the images, though I couldn't see a dramatic difference between those and my Canon L still lenses, particularly the 70-200.
Run&Gun
Veteran
The CN-E's are based on their still cousins(except the newest 20mm, there is no 20mm Canon still lens). Besides the obvious mechanical differences, the CN-E's do have different coatings and an 11-bladed aperture instead of 9(?), so you get those great round OOF highlights. The still lenses are just a tick cooler/"more neutral" to me if you're doing a side-by-side, but they were designed for different purposes. You can intercut them with minimal tweaking or maybe none at all. I do shoots all of the time where I'm using Canon Cine glass and the other cam may have Canon L lenses. Even those of us that have a bunch of "cine" lenses still pull out the 'ole 70-200 at times, because it is just such a damn good lens. I was actually hoping that Canon was going to make a fully mechanical Cine version of their 70-200(like the Zeiss CZ.2). I feel they could have done a 70-200 T2.8 or 2.9 for under $10K, and I was prepared to call my dealer and order/pre-order the minute that announced it. But alas, it was the 70-200 T4.4 hybrid compact servo zoom. Not a bad lens, I've used it, but not what I wanted.
Abaddon
Well-known member
I definitely need the gears and such for my follow focus, so I'm gonna go with cine primes regardless. Though for some of the extreme wide shots I might stick with still lenses for half the price, especially if the shots are completely static and require no focus pulling. I hear mixed things about the adapter but I don't remember there being any issues with the Metabones. Not sure if I would need to get a PL adapter.
Just to wade in one more time on "crop factor" . First your confusion is common so don't be too downhearted.
Crop factor is only of value helping someone who is used to one format get a quick sense off what the field of view will be using a lens on the other sensor. The crop is in the sensor not the lens.
So lets say a on a full frame camera my field of view on a 50mm lens at 10' is say 10' wide and a 75mm at 10' is say 6 feet wide ( these widths are not accurate - I'm just making them up here) . Furthermore lets say you are used to Full Frame. Now when you put that exact same 50mm lens on the APS-C camera at 10' the width of the shot is now 6'.
So a 50mm lens on an APS-C sensor camera gives you the same image as you are used to with a 75mm on a FF cam. So for your own purposes you could say - the 50 has a crop factor of 1.5 on APS-C .
However I am used to APS-C so I do the opposite math . For me a 75mm has a crop factor of .66 when used on a FF camera, because its just like what I expect from a 50 on APS-C . (I think I did that right didn't I ? Hope I didn't reverse it. It does get confusing)
Anyway you can see that crop factor can be very confusing when 2 people have different frames of reference. But there is no difference between the FF and APS-C or any other lens type - a 50 is a 50 is a 50 . Its the sensor that differs and whether the lens happens to be designed to cover a larger or smaller area is only what makes it useable on a larger sensor.
Now on an FS7 where you can use a speed booster "crop factor" becomes a very useful concept because the speed booster actually allows you to get the field of view of a FF sensor on an APS-C sensor like the FS7 has. It does this just by optically squeezing the image down which also concentrates the light. Hence a 75mm FF lens using a speed booster on an APS-C FS7 will give aproximately the same field of view as a 50mm lens without the speed booster. Hence the Spd Booster adds a crop factor of .67 and as mentioned above if you have both kinds of metabones adapters you get 2 lenses for the price of one. Plus because the light is concentrated you also gain a stop of light and an f2.8 on the Lens barrel functions as if it were an f2.
Hope that all makes sense.
Lenny
Crop factor is only of value helping someone who is used to one format get a quick sense off what the field of view will be using a lens on the other sensor. The crop is in the sensor not the lens.
So lets say a on a full frame camera my field of view on a 50mm lens at 10' is say 10' wide and a 75mm at 10' is say 6 feet wide ( these widths are not accurate - I'm just making them up here) . Furthermore lets say you are used to Full Frame. Now when you put that exact same 50mm lens on the APS-C camera at 10' the width of the shot is now 6'.
So a 50mm lens on an APS-C sensor camera gives you the same image as you are used to with a 75mm on a FF cam. So for your own purposes you could say - the 50 has a crop factor of 1.5 on APS-C .
However I am used to APS-C so I do the opposite math . For me a 75mm has a crop factor of .66 when used on a FF camera, because its just like what I expect from a 50 on APS-C . (I think I did that right didn't I ? Hope I didn't reverse it. It does get confusing)
Anyway you can see that crop factor can be very confusing when 2 people have different frames of reference. But there is no difference between the FF and APS-C or any other lens type - a 50 is a 50 is a 50 . Its the sensor that differs and whether the lens happens to be designed to cover a larger or smaller area is only what makes it useable on a larger sensor.
Now on an FS7 where you can use a speed booster "crop factor" becomes a very useful concept because the speed booster actually allows you to get the field of view of a FF sensor on an APS-C sensor like the FS7 has. It does this just by optically squeezing the image down which also concentrates the light. Hence a 75mm FF lens using a speed booster on an APS-C FS7 will give aproximately the same field of view as a 50mm lens without the speed booster. Hence the Spd Booster adds a crop factor of .67 and as mentioned above if you have both kinds of metabones adapters you get 2 lenses for the price of one. Plus because the light is concentrated you also gain a stop of light and an f2.8 on the Lens barrel functions as if it were an f2.
Hope that all makes sense.
Lenny
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NorBro
Major Contributor
Crop factors are a problem because there are too many of them today; 1.2x, 1.3x, 1.5x, 1.6x, 1.7x, 2x, 2.88x... (these are all different cameras I'm thinking about WITHOUT SpeedBoosters).
And it's even more of a mess if you use SBs or different cameras that have corporate crops in various resolutions and/or framerates.
It's borderline impossible to know what you exactly need at any given moment.
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I think it's best to really keep it simple and let people learn on their own without all of the math (at least in the beginning).
In general, the numbers on the lenses one prefers usually decrease as the sensor size decreases or increase as the sensor size increases. (And I'm giving the benefit of the doubt here that one won't try to adapt a MFT lens on his or her FF camera.)
And it's even more of a mess if you use SBs or different cameras that have corporate crops in various resolutions and/or framerates.
It's borderline impossible to know what you exactly need at any given moment.
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I think it's best to really keep it simple and let people learn on their own without all of the math (at least in the beginning).
In general, the numbers on the lenses one prefers usually decrease as the sensor size decreases or increase as the sensor size increases. (And I'm giving the benefit of the doubt here that one won't try to adapt a MFT lens on his or her FF camera.)
I understand this exactly.. and I said a few times.. I know a 50mm is 50mm is 50mm .. and this is also what was "trying to say".. didnt I actually say the same as you have ?? of course its the sensor size that different ..
Liam Hall
Veteran
Sorry, Donny, I really don’t want to bite your balls here, but that’s not what you said. You said using two 50mm primes, one FF and one APS-C will produce two different images on an APS-C camera. That is not true.
Let's stop beating up Donny. If you want to see a real car crash in a comments section, check this out:
https://www.redsharknews.com/produc...t-gimbal-is-a-completely-unique-camera-system
I don't have much advice re lenses, except that I use the Sony 18-110 for donkey work (it's great, IMO) and Sony Full Frame E Mount primes for interviews (28/f2, 55/1.8 and 75/1.8 are gooduns, without the bulk of the 1.4 bigger brothers.) I do have the mark 1 FS7, though - and the lens mount is frankly crap if you've got a fast schedule and a team that isn't going to baby everything.
Ben.
https://www.redsharknews.com/produc...t-gimbal-is-a-completely-unique-camera-system
I don't have much advice re lenses, except that I use the Sony 18-110 for donkey work (it's great, IMO) and Sony Full Frame E Mount primes for interviews (28/f2, 55/1.8 and 75/1.8 are gooduns, without the bulk of the 1.4 bigger brothers.) I do have the mark 1 FS7, though - and the lens mount is frankly crap if you've got a fast schedule and a team that isn't going to baby everything.
Ben.
Bite away sir.. yes your right that is what I said.. which is not what Ben said.. I think Im losing the plot.. !!!
Seems Ive been a bit of a dick..(again
.. sorry guys.. peace and love ..Returning to the original aspect of the thread for a moment...
I have a feeling that you will be optically happy with any of the three brands mentioned for cine lenses. With the Zeiss and the Sigma lenses you will also find the Cine versions optically extremely close to their smaller 'still photo' cousins.
The earlier mention of play induced by adapters is a valid and potentially important part of your situation -- particularly if you are using the original FS7.
One aspect of the possible lens movement on focus pulls may be counterintuitive -- often the larger cine-style lenses will be slightly stiffer and require more torque for the focus ring. This stiffness combined with the greater rotation angle required for a similar focus pull will put more force on the adapter and thus make the image more likely to shift from any play. Obviously a PL mount will be better for these lenses because it reduces any of this movement. But you will absolutely need to have the PL adapter 'locked' to the camera - as mentioned earlier in the thread - by using an adapter with a 'support foot' and having that locked onto your support rods.
(Of course the flip side of this argument is that smaller still photo glass will require less torque and may be less likely to shift -- particularly if you can support the lens from the rods as well.)
But in either case, if you're thinking of going back and forth between different lens mounts/adapters you need to take into consideration the re-rigging time on the lens change.
There has also been some zoom lens mention earlier in the thread. Although I like having the shallow DOF from the Sigma 18-35 and 50-100, neither one is really par-focal -- which means that if you're trying to use them as 'variable primes' you need to lock in a focal length and then establish your focus markings once you've set your focal length. Change your focal length slightly and the focus points need to be re-done. Want to drive your assistant crazy? -- help your framing by doing a slow zoom in during a dolly shot so that all the marks need to change depending on where you are in the zoom! If you're shooting at an f/4.5 you can probably get away with it just fine, but if you're going for that shallow DOF look and working at f/1.8 (Yes, the Sigma T/2 lenses are really f/1.8, and it's the f/stop that determines DOF shallowness), it's not going to be easy getting the proper eye in focus!
Other small point -- someone mentioned the Tokina 28-70 f/2.6-2.8 as being parfocal. I have one that is close to parfocal - but close isn't good enough (except in horseshoes or hand grenades....). I also don't think this lens would in any way match the crispness of the primes (although it does have a pleasing look) -- so I'd stay away -- I use mine primarily when I'm trying to smooth out skin tones/wrinkles that are too harsh with a really sharp lens.
Liam Hall
Veteran
Lol that’s some crazy s*%t right there.
Abaddon
Well-known member
I should have mentioned I have the FS7 Mark II, so it's a lot sturdier. When I tried the Canon primes, I didn't notice any play while focusing. Seemed pretty solid overall. I've never used a PL mount on the camera so I can't compare. I'm fine with renting PL lenses if they'll be more reliable. I mostly just want the best image quality within the price range of these brands. I could use still lenses as well but I hate having to strap on gears and other components that could slip or get misaligned.