Deep Focus Lens ala Citizen Kane

[Paul Sedillo]

I just finished reading an article in MovieMaker magazine which listed the 25 most influential directors of all time. At number 5 was Orson Wells. The brief talked about his use of a deep focus lens that was created specifically for this movie.

Now forgive my "newness" to the video world, but isn't it possible to pull this effect of with the current assortment of lens available? If so how do you do it?

Thanks!

[Clayton Farr]

<<<-- Originally posted by Paul Sedillo: ...isn't it possible to pull this effect of with the current assortment of lens available? If so how do you do it? -->>>

Hi Paul,

Actually you are in luck if you are referring to most consumer/prosumer DV cameras. If you take a look at some of the threads in this section (re: P+S Technik) or the "Toward a Film Look" you'll notice that most people are fighting against this native deep Depth of Field (or 'Deep Focus' as you put it) in DV.

Due to the way optics work, the smaller the format you are shooting with (ie - 16mm vs. 35mm film) the more inherent DOF you will get. When you consider that most consumer/prosumer DV cameras have 1/4 - 1/3" chips there is already *a lot* of DOF natively there.

You can further extend this by adjusting a couple of the other factors that affect DOF: aperture (smaller aperture / higher f-stop = more DOF); focal length (wider lens / wider end of zoom = more DOF); subject to camera distance (farther away from camera = more DOF).

Add these up and you probably have options that would make Gregg Toland jealous even with his f64 lenses and light banks that rivaled the power of the sun.

Now all you need to worry about is composition, lighting, and finding or making something interesting to put in front of the lens...

Enjoy,
Clayton

[Jeff Donald]

Depth of Field has been visited here many times. Most recently here *http://www.dvinfo.net/conf/showthread.php?s=&threadid=2452&perpage=15&highlight=DOF&pagenumber=4 * The last post should answer most questions concerning DoF.

Depth of Field does not change with the format. It only appears to change because a wider angle lens must be used on the smaller format to acheive the same angle of view. The use of a wider angle lens changes DoF.

Jeff

[Clayton Farr]

<<<-- Originally posted by Jeff Donald: Depth of Field does not change with the format. It only appears to change because a wider angle lens must be used on the smaller format to acheive the same angle of view. The use of a wider angle lens changes DoF. -->>>

Jeff,

I think this is a bit of semantics. Just to clarify what I meant:

Format = physical size of the exposable image area, whether it be silver halides, glass tubes, CCDs, or some magic stone tablet. That is in this case, format does not = medium.

And as you indicate, format certainly affects the 'relative' focal length, or maybe better said - the wide/tele nature - of a lens. (A 20mm 'wide' lens in 35mm format is not comparable on 8mm, 16mm, medium format, etc.) So yeah, technically I'm right with you.

But I think it unnecessarily confuses matters to say that format does not affect DOF since the range of focal lengths available is feasibly restricted within a given format. (Both by availability and useability.)

For example:

How commonly available, or for that matter used, is a 35mm lens wide enough to *readily* approximate the 'standard' DOF of something like a prosumer (smaller chips) DV camera - without using extreme f-stops and the light they would require? (I'm guessing that our 20mm wide lens would need to be around 3mm and then we get into extreme image distortion and everything...)

And conversely even if you could stick on a long enough lens onto said DV camera to cut down DOF to something in the range of 35mm how useable would this setup be with all of your action needing to be 50 yards away?

So maybe a better term is the 'workable DOF range' varies by format: smaller formats natively have a deeper/longer workable DOF, etc?

Sorry for the seeming rant, hopefully it makes some sense - I kind of forgot where I started... ;)

2 cents worth,
Clayton

[Jeff Donald]

Hi Clayton,

I'm not trying to make a big deal out of this, or (hopefully) be too *nal retentive about it either. However, Depth of Field is one of, if not the most talked about and least understood topics here. I strive merely to be very accurate in my definitions and explanations so that this may help other and not confuse them.

Changing the size of film, CCD, tube etc. does not change the Depth of Field. However, it is a common misconception that it does. The post that I referred to has the complete explanation of what affects DoF. As far as achieving a wide angle of view with smaller chips, the Canon 3x lens for the XL1 is 3.4mm F1.6 and is the equivalent to 24mm in 35mm film terms. It is not severely distorted as you suggest and can be even go wider with several WA adapters available.

I don't mean to dwell on this, but I felt it necessary, in the interest of accuracy to restate my original post. Thanks for your understanding.

Jeff

[Clayton Farr]

Thanks Jeff,

No offensive taken.

<<<-- As far as achieving a wide angle of view with smaller chips, the Canon 3x lens for the XL1 is 3.4mm F1.6 and is the equivalent to 24mm in 35mm film terms. It is not severely distorted as you suggest and can be even go wider with several WA adapters available. -->>>

Actually, what I meant was needing to use something like a 3mm lens on a 35mm camera to approximate the 'standard' depth of field one has with DV cameras. (This is per my rough memory of DV prosumer cams being around a 7x factor for focal length of 35mm lenses - at least that what I recall from using the EF adapter on the XL1...)

What I meant is that it would be pretty difficult to obtain the available DOF of DV cameras with 'standard' (non-distorting) 35mm lenses. [Given all other factors being the same - distance to subject, etc.]

This is of course all based upon the assumption that I am remembering my somewhat repressed film school learnin' correctly... Or it could speak to the quality of that learnin... ;)

Thanks for the link to the other thread as well.

Best,
Clayton

[Paul Sedillo]

Thank you both for replying to this question.

Jeff,

That link was just what I was looking for!

[Justin Chin]

Jeff:
I guess we're all dancing around some semantics here. Let's see if I can elaborate.

35mm cine lenses inherently have a larger diaphragm BECAUSE of the larger format. The lenses are made to project to a larger image plane.

It is because of this fact that when you use an EF adapter on your XL1 with a 35mm still lens you do not get the full focal length the lens is designed for.

F1.4 on a 35mm cine lens does not collate to an F1.4 on a video lens. The diaphragm opening at F1.4 on the 35mm cine lens is larger than that of a video F1.4.

So I guess the only question now is, if people really wanted shallow DoF, than the lens manufactures should start making lenses with physically larger aperture sizes. But they are not going to want to do that. It would be way too expensive. CLA 35 and Pro35 are the answer for now.

[Jeff Donald]

Justin,

I agree, the diaphragm opening (effective aperture, NOT F number) is a factor in DoF. This is what I stated in my previous post.

http://www.dvinfo.net/conf/showthread.php?s=&threadid=2452&perpage=15&highlight=DOF&pagenumber=4

The size of the CCD, tube, film etc. is not a factor in DoF.

Jeff

[Barry Goyette]

Hey y'all

I'm going to steer clear of the Dof wars for a second, and get back in the neighborhood of Paul's question.

The deep focus lenses that were used in Citizen Kane and other Welles films were essentially wide angle lenses with small minimum apertures. While the lenses themselves were only marginally "cutting edge", the techniques and concepts Welles and Toland used in the making of these films were indeed very state of the art. The wide angle lenses required sets to have visible side walls and ceilings, and this combined with the greater amount of light necessary due to the smaller apertures let to some rather sticky (and creative) lighting situations.

Now if the whole purpose of their efforts was to get the wallpaper in focus, this would have been big waste of time. Instead they created extremely elaborate "still" compositions within which the actors performed a delicate ballet of constantly changing arrangements, with important action going on in the fore, middle and far ground. It's truly amazing to see how dense the frame gets in "Touch of Evil", with 6 or 7 heads and torso's doing battle for every millimeter of the filmstock. And the fact that it actually works to advance the story makes it even more amazing.

Yes, Paul, modern lenses are all capable of the results Welles achieved in his groungbreaking films. And as has been said, dv can essentially do it without even stopping down (although the sharpness of a 35mm bw negative is lightyears beyond what a 1/3 inch chip can do). The question is, are there any directors with the cojones to attempt these techniques?...(and I guess. are they even relevant today?). Our modern aesthetic uses editing to create the densities that Welles created through composition. He was essentially at the forefront of moving film away from the theatrical tradition that it came from, by giving the camera a true point of view. We've come along way from that. And while it might be fun (or just frustrating) to try some of their techniques, I'm not sure it's anything more than an exercise to go back.

Barry

[Paul Sedillo]

Barry,

As always you ROCK! Thank you for digging into the question that I asked. Bartender, please buy this man his beverage of choice!

I have watched Citizen Kane several times trying to understand what Orson achieved.

Something that I had not thought of but makes complete sense, is the use of a wide angle lens. This in conjunction with the use of angles really created a stunning visual.

[Barry Goyette]

Out here the beverage of choice is tequila. If you ever see any Porfidio floating around houston, let me know. I'll be on the first plane.

While I was writing that, I kept thinking about some of Woody Allen's late 70s "apartment" comedies, and a technique that he used that in many ways pokes a little harmless fun at welles deep focus. Like Welles, Allen is fond of a static camera, where the actors are allowed to move around in the frame. But if you watch some of his films closely, you'll see the camera often parked in some hallway, while the characters pace back and forth, spending most of their time OUT of the frame, rarely, if at all, delivering their lines on camera. It's a mesmerizing, and funny technique, that, I think, consciously refers back to Welles, yet perfectly captures the scene, and probably in a more modern and realistic way.

Cheers

Barry

[Clayton Farr]

<<<-- Barry, As always you ROCK! Thank you for digging into the question that I asked. Bartender, please buy this man his beverage of choice! -->>>

Sorry, I guess I took you a bit too literal in asking "how to pull this off" instead of why? - Which Barry's aesthetically articulate answers nail wonderfully.

<<<-- Something that I had not thought of but makes complete sense, is the use of a wide angle lens. This in conjunction with the use of angles really created a stunning visual. -->>>

Hey now, come on Paul - I think Jeff and I at least deserve a seat at the bar, we did mention that much... ;)

Best,
Clayton

[Paul Sedillo]

<<<-- Originally posted by ClaytonF : <<<-- Barry, As always you ROCK! Thank you for digging into the question that I asked. Bartender, please buy this man his beverage of choice! -->>>

Hey now, come on Paul - I think Jeff and I at least deserve a seat at the bar, we did mention that much... ;)

Best,
Clayton -->>>

Barkeep drinks are on me for Clayton, Jeff, and Barry!

[Barry Goyette]

I found an article this morning on the history, technical aspects, and aesthetic of deep focus, at least in how it relates to Greg Toland, cinematographer of citizen kane.

http://www.bfi.org.uk/sightandsound/archive/innovators/toland.html

Barry