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FF35mm / 5DII / Vista Vision / Scarlet / Epic DOF nightmares...

Tom Lowe

Tom Lowe

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I was messing around with some DOF calculators, trying to figure out how the hell I am going to keep anything in focus on the new 5D Mark II, or Scarlet/DSMC or Epic if they do end up with full-frame 35mm sensors. The 5DII's format is similar in size to Vista Vision.

So, if I have the 24mm 1.4 L lens on the 5DII, trying to shoot in low light, wide open, here is what the DOF calculator tells me will be in focus:

Subject distance 10 ft

Depth of field
Near limit 8.18 ft
Far limit 12.9 ft
Total 4.69 ft
In front of subject 1.82 ft (39%)
Behind subject 2.87 ft (61%)
Hyperfocal distance 44.6 ft
Circle of confusion 0.03 mm

Hyperfocal:

Subject distance 44.6 ft

Depth of field
Near limit 22.3 ft
Far limit Infinity
Total Infinite
In front of subject 22.3 ft
Behind subject Infinite
Hyperfocal distance 44.6 ft
Circle of confusion 0.03 mm

So if I'm shooting low-light landscapes, everything closer than 22.3 feet away is going to be out of focus or very soft? :umm:

Compare that to Red One with a 15mm T2 (a fairly realistic setup)...

Subject distance 10 ft

Depth of field
Near limit 6.61 ft
Far limit 20.5 ft
Total 13.9 ft
In front of subject 3.4 ft (24%)
Behind subject 10.5 ft (76%)
Hyperfocal distance 19.5 ft
Circle of confusion 0.019 mm

Hyperfocal:

Subject distance 19.5 ft

Depth of field
Near limit 9.74 ft
Far limit Infinity
Total Infinite
In front of subject 9.8 ft
Behind subject Infinite
Hyperfocal distance 19.5 ft
Circle of confusion 0.019 mm

Big, big difference. This is kind of scary to me in terms of trying to keep much of the frame in focus. :help:
 
I'm not sure why one would expect much depth of field at T/1.4 anyway -- but if you do, the main thing is that something is noticeably sharp in the frame.

It's the same problem of shooting in 35mm anamorphic, you have to think about where to place the focus, you can't expect everything to just hold unless you are in sunlight at a decent f-stop.

Sometimes a shallow-focus effect in wide landscape shots can be attractive because it's unexpected and you get the sensation of more three-dimensional depth, oddly enough, because of the soft foreground elements and sharper background (or vice-versa) in a 2D image. You look at some of the shallower-focus landscape shots in 70mm movies like "2001" or "Lawrence of Arabia" and it can be quite pretty on the big screen to have soft elements surrounding a sharp area of interest.

But certainly focus-pulling of closer objects that are moving (like actors) is very hard with large-format cameras when shooting at T/1.4 - it's hard enough in 35mm doing that. Sometimes you just have to do what people shooting anamorphic often do -- bite the bullet and try to get to a higher f-stop. Most of "The New World" was shot on faster film stocks in order to shoot at deeper stops outdoors in 35mm anamorphic (and a little 65mm).
 
David, how fast are the fastest anamorphics? I don't know much about them.
 
Same as the fastest sphericals, basically the same optics converted into anamorphic.

For example, Panavision High Speed anamorphics are around T/1.4, with a 50mm T/1.1 listed, probably built from elements from a 50mm T/1.1.

I recall JDC also adapting some Zeiss Super-Speeds into anamorphics.

I didn't say they were particularly sharp however...

The modern, sharp T/1.4 Zeiss Master Primes are some of the biggest spherical cine primes on the market and would become gigantic if ever adapted into anamorphic, but they would be sharp. Look at the Primo anamorphics -- they are T/2.0 like their spherical Primo counterparts, but much bigger and heavier. You have to figure that for front anamorphic elements to cover the front of a spherical lens, it probably ends up being twice as large. Hence why Joe Dunton's anamorphics mostly were built from older but smaller Cooke S2's and S3's. Converting a set of Cooke S4's into anamorphic would have resulted in huge lenses.
 
i hope you are resting easier, tom. selective depth of field can be one of the most powerful elements in visual storytelling, and something that people in the HD/video world have been starving for (hence all the 35mm DOF adapters)...just to get that "cinematic" look. sensor size could easily be considered one of Red One's many supreme advantages over current HD cinema solutions.

reserve your dream-filled moments for better use: like how you can take some of the epic visuals from malick's work and apply them to your own storytelling.

leave the nightmares to your skilled AC.

cheers, and happy shooting!
 
a further word on shooting wide open...this should make you, your AC, and anyone associated feel lucky to be shooting at T/1.4, and to have a more sensitive stock (or sensor) than 100 ASA.

Taken from a website devoted to the late John Alcott (who shot some of Kubrick's masterworks):

on 'Barry Lyndon': 'There was a great deal of testing of possible photographic approaches and effects - the candlelight thing, for example. Actually, we had talked about shooting solely by candlelight as far back as '2001', when Stanley Kubrick was planning to film 'Napoleon' but the requisite fast lenses were not available at the time. […] The objective was to shoot these scenes exclusively by candlelight - that is, without a boost from any artificial light whatsoever. Stanley finally discovered three 50mm f/0.7 Zeiss still-camera lenses which were left over from a batch made for use by NASA in their Apollo moon-landing program. We had a non-reflexed Mitchell BNC which was sent over to Ed Di Giulio to be reconstructed to accept this ultra-fast lens. He had to mill out the existing lens mounts, because the rear element of this f/0.7 lens was virtually something like 4mm from the film plane. It took quite a while, and when we got the camera back we made quite extensive tests on it. This Zeiss lens was like no other lens in a way, because when you look through any normal type of lens you are looking through the optical system and by just altering the focus you can tell whether it's in or out of focus. But when you looked through this lens it appeared to have a fantastic range of focus, quite unbelievable. However, when you did a photographic test you discovered that it had no depth of field at all - which one expected anyway. So we literally had to scale this lens by doing hand tests from about 200 feet down to about 4 feet, marking every distance that would lead up to the 10-foot range. We had to literally get it down to inches on the actual scaling. […] The point of focus was so critical and there was hardly any depth of field with that f/0.7 lens. My focus operator, Doug Milsome, used a closed-circuit video camera as the only way to keep track of the distances with any degree of accuracy. The video camera was placed at a 90-degree angle to the film camera position and was monitored by means of a TV screen mounted above the camera lens scale. A grid was placed over the TV screen and by taping the various artists' positions, the distances could be transferred to the TV grid to allow the artists a certain flexibility of movement, while keeping them in focus. [...] There was also the problem of finding a side viewfinder that would transmit enough light to show us where we were framed. The conventional viewfinder would not do at all, because it involves prisms which cause such a high degree of light loss that very little image is visible at such low light levels. Instead, we had to adapt to the BNC a viewfinder from one of the old Technicolor three-strip cameras. It works on a principle of mirrors and simply reflects what it 'sees', resulting in a much brighter image. There is very little parallax with that viewfinder, since it mounts so close to the lens. […] In the sequence where Lord Ludd and Barry are in the gaming room and he loses a large amount of money, the set was lit entirely by the candles, but I had metal reflectors made to mount above the two chandeliers, the main purpose being to keep the heat of the candles from damaging the ceiling. However, it also acted as a light reflector to provide an overall illumination of top light. […] Roughly, three foot-candles was the key. We were forcing the whole picture one stop in development. Incidentally, I found a great advantage in using the Gossen Panalux electronic meter for these sequences, because it goes down to half foot-candle measurements. It's a very good meter for those extreme low-light situations. We were using 70-candle chandeliers, and most of the time I could also use either five-candle or three-candle table candelabra, as well.' [From article in 'American Cinematographer', December 1975.]

talk about razor-thin focus pulls!

http://www.cinematographers.nl/GreatDoPh/alcott.htm

i think this kind of ingenuity demonstrates that if there is a conceptual idea or approach that will support the storytelling, no matter how great a challenge it may pose, it is possible to accomplish it. to what lengths one must go to achieve it...well, that of course will vary. but as the germans say, impossible is nothing.
 
hehe.

not only would i be worried about a 1st AC being able to pull focus in low light on narrative film or music video or commercial projects, but even worse, i am worried about being able to pull focus MYSELF while i'm out shooting landscapes or cutaway-style shots. part of the beauty of the 5DII or Scarlet will be the ability to throw it into a backpack and hike it 5 miles up a trail into the mountains or into urban places you simply could not get away with dragging a full cinema camera into. i'm much more concerned about how ONE PERSON can possibly shoot with a fast lens, a huge sensor like FF35mm, and probably some really weird ergonomics.
 
Rudi Herbert said:
Autofocus :-)
Click to expand...

It does not work at night.

Accurate focus markings and laser distance meter is the way to go. Unfortunately only PL lenses offer accurate focusing scales and no still picture camera accepts PL lenses...:help:
 
Pawel Achtel said:
It does not work at night.

Accurate focus markings and laser distance meter is the way to go. Unfortunately only PL lenses offer accurate focusing scales and no still picture camera accepts PL lenses...:help:
Click to expand...

Hi,

PV Primos have good focusing marks, probably not so difficult to adapt to a still camera as well.

Stephen
 
Tom this seems something of a turnaround from your requests for Vistavision sized sensor on the Epic.

However - who says you have to shoot wide open (very few narrative films to this as a general rule) - Anamorphics generally have to be lit up to T4 to hit the point at which the lens becomes sharp - so not much stuff is shot wide open on anamorphics unless the Dp is struggling. You could always shoot at T4-5.6 (the lenses will be sharper here anyway).
 
Tom said:
Do you think the AF on the 5DII and Scarlet will be good? :unsure:
Click to expand...

On the 5D II, no. Even the owners manual warns against using it during a shot.

For getting initial focus, I'm guessing the autofocus will be fine -- just as good as using it like a stills camera. But Canon did not redesign the autofocus to be similar to video camcorders' autofocus -- it will apparently autofocus like a still camera even while recording video.
 
jtm said:
Tom this seems something of a turnaround from your requests for Vistavision sized sensor on the Epic.
Click to expand...

Hehe. Yeah, kind of like the dog who chases after the car and then doesn't know what to do with it once he catches it. :)

You're right. For most daylight situations you would be stopped down quite a bit. But I specifically have some ideas about shooting in extreme low light, and that's what worries me the most.
 
David Rasberry said:
PL lenses won't cover full frame 35mm anyway will they?
Click to expand...

No, but it would be a nice option to be able to use PL lenses on a crop sensor still camera.
 
Tom said:
Do you think the AF on the 5DII and Scarlet will be good? :unsure:
Click to expand...

Tom, I was halfway kidding of course :-) Having said that, I made my peace with AF for stills a long time ago and learn to harness the system to my needs so that I can select whatever part of the scene in want in action and freeze with the lock button...after a while, I've never seen a reason for going back to MF on stills, but then again, moving images would be a whole new world...Which is why, for me, the Canon or Nikon cameras would never function as a true replacement for cinema applications. Manually focusing with those lenses IS difficult, and ascertaining critical focus through those tiny viewfinders, well, good luck with that. A friend of mine who does a lot of location scouting in Europe just bought a D90 because he can both photograph the locations and get decent videos of them and then send it back to the producers, but that is as "filmic" as I would get with those cameras. A scarlet if it is still under 5K, or even an EX1 (which, don't let anybody tell you differently, makes BEAUTIFUL images) would be the way to go for filmic images on the "cheap". Then again, I'm certain the Scarlet will have a stills feature besides its 24p capabilities, making all these "gonna get me a 5D or a D90" rants needless anyway....
 
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