The Shot You Can Make
Sunday, January 9, 2011 at 10:50PM There are some exciting new camera options out there these days, ranging from inexpensive, large-sensor hybrids from the likes of Panasonic and Canon to groundbreaking high-end digital cinema rigs from folks like RED and Arri. When contemplating buying or using these cameras, one has many resources to evaluate things like focal length equivalencies and depth of field. This chart from Barry Green is a great example — it’s extremely helpful and the kind of thing you could refer to again and again.
In fact, if you’re like me, you’ll need to refer to it again and again, because there’s nothing really intuitive about it. It’s a bunch of numbers. You might find yourself staring at it and thinking, “Yeah, but what kind of shot can I actually make with these camera/lens combinations?”
Read down the thread on DVXuser and you’ll see one member exclaim with glee that with only three Panasonic zoom lenses, he can cover every focal length from 7mm to 300mm on his Micro Four-Thirds (MFT) rig. Barry quickly points out that this is true, but at undesirably slow apertures. The poster is, I’m sure, left scratching his head, trying to grok just how these slower lenses are going to affect the cinematic look and feel of his shots.
You can feel my own frustration with this in my article on the Panasonic AF100. I discussed there the dilemma of MFT — is it “big enough” for cinema? Yes, but if you want cinematic DOF, you’ll need fast lenses, faster than most of what Panasonic makes.
Another example — you might be looking at the recent demonstrations of the fixed-lens RED Scarlet and wondering just how much DOF control you’ll have with an ƒ2.4 lens on a 2/3” sensor.
All the charts and sensor-size comparison images and spec sheets won’t answer the question: “Yeah, but what shot can I make?”
So I’m introducing a new Prolost feature designed to help answer that question. It’s called the Shot You Can Make (SYCM) Simulator, and it’s sort of a 3D “Marcie” for focal length and depth of field. Here’s what it looks like:
;)
I started with a shot from a movie called 12 Rounds. Directed by Renny Harlin, 12 Rounds is an action flick set in New Orleans and starring WWE’s John Cena. It’s the kind of movie you can rely on to contain the kinds of shots you see in many movies — in this case, a guy (Cena) with a gun. The focus is on Cena’s face, the gun is slightly soft, and there are a few big, boke-liscious out-of-focus lights in the background.
;)
12 Rounds was shot with Panavision cameras on Super 35mm film. My guess is that this particular shot was made with a 125mm Panavision Primo at ƒ2.0. Based on this estimation, I simplified the image into cartoon-shaded layers and split them out in 3D in Adobe After Effects, essentially recreating a simplified model of what was in front of the lens that night. Using a lens blur plug-in rigged with expressions, each 3D layer gets the correct amount of defocus for its distance from camera. The result is a simulation of the shot with accurate angle of view and depth of field.*
The shot contains a number of recognizable things, like a man, a hand, a gun, and some distant lights. If you’re familiar with your camera — any camera — you can probably easily imagine what kind of shot of this setup you could make. But what about a camera that you’re not familiar with?
The Shot You Can Make Simulator allows me to place any camera I want, with any lens, at any stop, into this same scene, and re-photograph the virtual scene with that rig. In this way it provides a real-world-ish benchmark for the kind of lens performance that matters most to filmmakers:
- What’s the angle of view, i.e. how wide or telephoto is this lens?
- What kind of depth of field performance can I expect? I.e., what will be my ability to isolate my subject from the background using focus?
Here’s an example. Simulating a Canon 5D Mark II with a 50mm lens at ƒ1.4, you can see that I’ve had to move closer to my virtual Cena to achieve similar framing. His hands appear larger, and much softer. The lights in the background are still blooming, but not as much. Although we’ve opened up about a stop and focused closer, we’ve also gone wider in AOV, so our ability to make big circles in the background has diminished.
;)
Another example, this time simulating the shot you might make with a Canon 5D Mark II using the Canon 70–200 F2.8 II IS, at maximum zoom:
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Note that we now have a slightly narrower Angle Of View than the Super 35 125mm baseline, so we’ve stepped back a bit to maintain the framing. But despite focusing longer and stopping down, we have a much larger image sensor on the 5D, so we maintain the same “feel” in terms of the softness of the gun barrel and the size of the background boke.
Now, if someone tells you that 200mm on a 5D Mark II is a decent rough match for 125mm on Super 35, that’s useful information. But unless you’re a Cybog Killer from the Future, you might have a hard time getting a sense of how all the other factors will balance out — slower lens, but larger sensor, but longer focus, but more money left over for tacos.**
I was trying to explain to someone the other day why I felt that the MFT zooms Panasonic has on offer are not very sexy. Maybe this will help — here’s the same shot at 140mm ƒ5.8, the max zoom of a popular “do it all” MFT lens from Panasonic:
;)
Even though we’re zoomed way in, tighter than the baseline shot, we can just barely soften the background, and the gun is razor sharp. Interestingly, the Shot You Can Make with the Panasonic 14–140mm is not unlike the Shot You Can Make with a Canon HV20, which has a tiny sensor by comparison, but a surprisingly fast lens. Here’s the HV20 making the shot at its max zoom of 61mm, ƒ3.0:
;)
The similarity between these images shows that you can very easily slap a lens on a MFT camera that will completely undo any perceived DOF advantage of the large sensor. To me, this is useful information. If you agree, I’ll use the SYCM Simulator to profile lenses and cameras I discuss here.
* My respect for you the reader demands that I generally avoid disclaimers, but in this case I would like to point out that this is all guesswork on my part, from the original lens used to the dimensions of the set. And I could very likely have my math wrong on any of the DOF calculations too. Please let me know if anything jumps out at you as wrong.
** Tacos have not yet been integrated into the SYCM Simulator.
Stu
Be sure to also check out this camera/lens comparison tool from Abel Cine. I’d been looking for the link when writing this, but luckily Jason Wingrove helped me out on Twitter.
Stu
Those of you asking about a mobile app version of the SYCM Simulator, be sure to check out this follow up post.
Reader Comments (22)
Awesome. Perfect. Thanks.
I think this is a great idea. Can you do us all a favor and add in the look of the likely scarlet with its 2/3" sensor and its fixed lens? Would be greatly appreciated to see what sort of looks it will offer in this example.
Great article thanks for posting,
How did you scale the after effects scene in relation to real world scales? It would be interesting to know how the ae camera settings/scene scale relate to the real world...
Stu, this is awesome, thanks for these informative posts. Speaking for myself, your straightforward perspective on technical aspects of filmmaking have taken me a very long way in understanding all of this.
I can't find the AE project. Or is it no download?
Hi Floris, the AE project is not particularly user-friendly, so it's not my intention to make it available just now.
I don't think the math is so difficult: just divide by the crop factor
if you want an image with the same FoV and DoF of a full-frame 50 mm lens at f/2.8 aperture, and your camera uses a 1.6x crop factor, you need a 32 mm lens (50/1.6), set at f/1.75 (2.8/1.6)
if your reference is 35mm film and you're using a GH2, just use the relative crop factor, in this case 1.2x (1.9/1.6); so if you want an image with the FoV and DoF of a 30mm f/2.0, you need a 25mm (30/1.2) set at f/1.7 (2.0/1.2)
super nice tool, though!
so far i have no troubles with low light with my af100
its clean at 1250 iso and i can use my nikon lenses even g lenses easily.
I think weve come to a point in filmmaking where DOF is no longer a must have but how much do we need it because were already at the large sensor age of digital cinema and achieving SDOF is easy.
great article and a pretty cool tool!
the good thing for all the 5d users is, that you can achieve a cinematic look with a slower (less expensive) lens. so the 70-200 f.4 lens is a workable lens for movie-production.
So when is this app going to be available ;-)
I know there's no iphone app, but it's usefulness should be obvious: a handy learning tool; it would keep people from talking numbers; it could settle pub disputes; simulations make abstraction unnecessary.
I learned this from building houses: don't measure a plank unless it's impossible to hold it up and mark it precisely. Why go through the abstraction layer of tape measures? (It's imprecise. Every translation introduces noise.)
iPhones remove the abstraction layer of keyboards and mice from computers. A two year old can be expected to work 1 key on a keyboard and have zero mouse skills - but she could use an iPhone without any problem.
I think it's a genius tool. Look at the chart. Look at the picture. It's a simple matter of information design. Data about images really ought to be presented as simulated images. That's where all the value is. I'm very excited by the implications of this tool.
I'd vote to see some Scarlet 3K both fixed (f/2.4) and interchangeable mini primes (f/1.8?) shots. Also some bare EX1 1/2", something that we can get our hands on today for a comparable amount of money.
Some anamorphic shots would be cool (although maybe harder for you?), to compare DOF and FOV with spherical options.
How do you get the sensor size, f stop, precisely simulated? most of these lens blur plugins don't have reality-based parameters, or am I wrong?
This is awesome. Truly the best way of gauging all the different stats. Certainly if you could turn this into an iPhone app somehow, you'd make some serious money.
And I also vote for adding the Scarlet fixed lens to the list as well. And the AF100 or the new Sony too.
Too cool. Thanks for always making things clearer.
This is amazingly valuable. Fantastic work, Stu! As you know, to eliminate the guesswork on which the rest of the measurements are based, you could always ask a friend to assume the same gun-toting pose while standing in front of a nighttime skyline.
I too am curious about the SYCM with a 2/3" sensor and the proposed RED mini primes. What were they, T1.6?
Stu, great comparisons. Always good to see the results than read off numbers from a chart. My vote is also for Scarlet comparisons, more specifically the new line of Red cameras that will be released, all wide open, to get a sense of the mix DOF across the diff models. So: Scarlet fixed (T2.8), Scarlet cinema (T1.8), and Epic S35.
Mr Maschwitz, as always invaluable analysis posted with true knowledege and insight. Please keep the blog flowing. SYCM is going to be genius for simple PreViz analogies. Please if you have the time put all new RED combinations UP. As well as a canon5D/ nikonAIS marrriage. Keep it coming. K.
Put me down for the iPhone version. I bought the David pretty good Pcam app, paid £18 for it - which I guess is expensive for an app, but I use it a lot on jobs and so it seems pretty reasonable. However, it doesn't do this...
There's a whole bunch of applications and charts that tell you what the FoV is for pretty much any camera and lens combo under the sun, and a whole host of others that help a focus puller calculate their splits, but mostly I just want to see if a shot is going to LOOK GOOD.
With the current vast array of sensor sizes and lens options it's almost impossible for any DP or director to have a good idea of what all those combos will yeild, particularly at the margins of the available rigs. I think a well priced, commercial version of SYCM would get a lot of interest.
I guess more complex development for someone would be to have it leverage one of the iPhones 3D games engines (Unity / Unreal etc) so that a low poly figures could be used to sim lens / sensor combos in a bit more detail, which might help with 2 shots and conversations... Alright, now i'm just dreaming.
Hell, I know a lot of people (me included) that would buy the baseball card, gun toting wrestler version, and use it tomorrow....
Stu, you said the GH2 has a crop factor of 1.2. That would indicate a bigger chip than the 1DMKIV. I think you meant a 2.0 crop, unless I'm reading that wrong.
I didn't write that. If you're referring to Samuel's comment, it looks like he's referencing 35mm motion picture film. The MFT crop factor in relation to full-frame stills cameras such as the 5D is 2.0.
I do not use the Panasonic kit lens for DOF shots, that's why I have other lenses. Seems everyone loves to bash the little GH1, but it still produces really nice video, especially with the hack. The Zacuto shootout almost seemed like Canon was sponsoring it. Even when there was a great GH1 result, no one said a thing.
I would love to get the 5dmk2 against my GH1 and see. Anyone near Nw Indiana want to put it all on the line?
Hi Stu and thanks for your help before. I would like to see the lens you mentioned in your GH2 post used over on Mr Bloom's blog included in the roundup...you know that amazing little voigtlander f0.95?
I'll add my voice to others. An app like this that can run on iOS and perhaps other mobile platforms would be truly brilliant. A picture is worth a thousand words but you could easily have a little flip button in the corner of each example which could flip over to reveal charts and graphs for all those sciency types who like to overcomplicate the world.
There is a Photoshop (R) plugin, Alien Skin's Bokeh (TM), that offers a similar depth of file post affect for stills and knows all kinds of still lenses from Canon and Nikon. It can turn an F22 shot into F1, bokeh out the background and can even do heart shaped highlights. Maybe Alien Skin can work with you to make the iPhone app. See www.alienskin.com for a 30 fully functional trial.
hey Stu,
it would be really nice if you could release the afx project data for "the shot you can make". Or even better release a tutorial on how to set it up. I'm sure it would help so many people in planning their shoots with some nice animatics/pre-viz videos..
Regards