The Pitfalls of Anamorphic

Written by Art Adams on July 26th, 2013

Anamorphic lenses seem to be making a comeback. I’m both thrilled and terrified by this. I love the look, but I’ve worked with anamorphic lenses before, and I know what goes on behind the scenes. Read on and you will too…

I only worked on a couple of anamorphic shows and that was almost 20 years ago. Some of what I’m going to describe may not be an issue anymore, but at least you’ll know what to look for on your first anamorphic job. When I was a camera assistant, many many years ago, one of my regular DP’s called me up about a possible doc-style shoot for Lockheed. We were going to shoot a test pilot as he suited up and prepped for flight, and then follow him out to the plane and show him taking off. The entire project was to be shot handheld… and anamorphic.

I should have run away screaming. Instead I said, “Okay, sure!” I had no experience with anamorphic. How hard could it be? Lenses are lenses, right?

Fortunately the job turned out to be someone’s pipe dream and it never happened. I later discovered that anamorphic lenses are strange beasts. The anamorphic look is wonderful but they don’t function the way other lenses do. There’s quite a lot to know before you take on an anamorphic job as a DP, operator or assistant.

From the DP’s perspective, anamorphic means more light and bigger sets. Most spherical lenses aren’t terribly sharp wider than T2, and they often turn to mush at T1.4. Anamorphic lenses rarely look sharp until T3.5 or T4. They may open up to T2.8 or T2, but if you try to use them that wide open you’ll often get a rude surprise when the image is projected. Some lenses are better at this than others, but not by much.

I heard one story where a feature film production went through several first assistants due to focus issues before one assistant pointed out that most of the movie was being shot at T2, and the lenses used didn’t actually focus at all at that stop!

Focus is a huge issue in anamorphic, and everyone on the camera crew has to wrap their heads around which focal length lens does what. For example, in spherical cinematography a 50mm lens delivers a “normal” perspective, but in anamorphic the closest to this is the 80mm. The reason for this is that each anamorphic lens is really two lenses in one: it’s 80mm tall but 40mm wide, for a 2:1 squeeze. A spherical 40mm lens isn’t all that long and focus isn’t that big a deal in the horizontal axis, but the addition of an 80mm lens to the vertical axis cuts depth of field in half. A 40mm spherical lens has reasonable depth of field, but add an 80mm lens into that mix and suddenly you have to pay a LOT of attention just to make sure medium shots are in focus.

A 35mm anamorphic lens is almost a fisheye, and a 180mm prime becomes the goto lens for closeups. Imagine pulling focus on a 180mm lens 6′ from an actor’s face. Yikes!

Assistants had all sorts of tricks to keep actors in focus, up to and including tying the actors to the dolly or the operator with a piece of rope. One assistant told me that depth of field falls primarily behind the point of focus in most anamorphic lenses so when in doubt it helps to pull focus forward a little. Depth of field distribution varies based on the lens design so this sounds reasonable: while we’re taught in film school that 1/3 of the depth of field falls in front of the point of focus and 2/3 falls behind, Zeiss spherical lenses distribute it closer to 50/50–so it seems reasonable that some lens designs would skew that the other way.

In general, though, it helps most to light sets to at least T4, and brighter for closeups when at all possible.

In the days of film it was always a toss-up as to who got fired first for soft focus: the assistant for not hitting the right mark, or the operator for not seeing that the shot was out of focus. The first time I found myself on an anamorphic film as an operator I looked through the viewfinder and cringed: the widescreen image in the viewfinder was really wide but not very tall, and so small that I couldn’t see focus at all! At the first break I called a business agent at Local 600 who was a former operator with a lot of anamorphic experience.

“How the hell do I see focus?” I asked him.

“Look at the image squeezed,” he said.

I went back to the camera and flipped off the “de-anamorphoser,” which is an optical element that un-squeezes the image in the viewfinder and makes it widescreen. Suddenly I had a big crystal clear image to look at, and I could see focus quite easily. Everyone in the frame was tall and skinny as the widescreen image became a square frame, but over time I learned to compensate for that in my head. I got so used to it, in fact, that occasionally I forgot to flip the de-anamorphoser back on when I walked away from the camera. The director grew quite worried when he looked through the lens and saw what I was really looking at, and it took some explaining to calm him down.

(One of the early anamorphic lenses had two focus adjustments that had to be operated by two separate assistants during the shot. This led to a lot of finger pointing when a shot was buzzed as it was always the other guy’s fault.)

These days the operator is off the hook: there’s simply no way to see focus in an HD viewfinder with a spherical lens, let alone an anamorphic lens. It’s all on whoever is watching the largest monitor on set–and that’s usually not anyone on the camera crew, which is slightly terrifying.

Wide anamorphic lenses tend to distort the sides of the image and they tend not to focus very close. That combination means that sets have to be built larger than they would for spherical shoots. The lighting budget then increases not only because of the size of the set but because you now have to light it to T4 or T5.6 instead of T2.8. The only time you’re not inconvenienced when shooting anamorphic is if you’re shooting day exteriors in a desert.

Using wide lenses on closeups is a particular problem. I heard one story where an assistant who prepped an anamorphic package for a feature rented an enormous number of white disks for the follow focus unit. He had three diopters that could end up in front of an anamorphic lens at any given time, so each lens had set of three focus disks pre-marked with focus distances based on diopter strength. If the DP called for a #2 diopter on top of an 80mm lens the assistant would pop the diopter onto the lens and then put up the “80mm #2 diopter” focus disk to give him accurate distance marks. Not only did he have three of these disks per lens but he had to have a duplicate set for the times when he had to work on the right side of the camera!

I worked on visual effects units on two features that shot anamorphic, and that’s where I learned that anamorphic lenses have two “nodal points.” The nodal point (which is how this point is usually referenced even though the correct term is “front entrance pupil”) is where the image “flips” in the lens such that the picture the sensor sees is reversed both vertically and horizontally. If the rotational axis of the camera+lens is centered on this point then everything in the frame will track in perfect perspective when the camera pans or tilts.

The reverse of this effect is really obvious when looking through a camera with a wide angle lens: as one pans left or right the foreground moves much faster than the background does, which is interesting when shooting live action but not so good for visual effects. Imagine a shot that shows a dozen horse riders galloping toward an enormous castle in the distance. In the old days this would have been done using a sheet of glass with a castle painted on it and a clear area left in the glass through which the riders would be seen. If the camera moved at all and it wasn’t centered on the “nodal point” the castle would move across the frame much too fast in relation to the horses and give away the trick. If the camera was centered on the nodal point then everything would track perfectly and the illusion was achieved.

Spherical lenses have one nodal point. Anamorphic lenses have two, one for vertical and one for horizontal–and they do not fall in the same place.

The nodal point is often centered over the aperture ring, but not always. I was taught to find it by putting two C-stands directly on the lens axis at different distances from the camera, and then moving the camera around on the head until the front C-stand perfectly blocked the rear one no matter how far the camera panned or tilted. It’s fairly easy to do this in the horizontal axis: just slide the camera forward or back (usually a LOT back) until the C-stands track. It was less easily done in the vertical axis because you have to raise or lower the camera, and most heads only allow you to raise it. In fact, every common fluid or gear head will put the camera and its “nodal point” way above the rotational axis of the head, because that axis is what the head rotates around. You have to use a specialized head like a Weaver-Steadman, Cartoni Lambda or Ronford in order to get both “nodal points” aligned when using spherical lenses.

I found this web page,, which gives a pretty good description of the alignment process.

As there are two “nodal points” in each anamorphic lens, and they aren’t in the same place, you can get perfect pans or tilts but not both at the same time. I did a number of shots on one visual effects project where I simply had to lock off the pan or tilt on the gear head to made sure I only ever moved the camera around one axis.

The last big headache about anamorphic lenses is that they tend to be very heavy. I haven’t worked with modern anamorphics, but I’ll remember for the rest of my life the one time I shot a closeup of an actor during a sword fight. The camera was a Panaflex G2–not the lightest film camera in the world–and our closeup lens was a 180mm prime that weighed more than the camera did. I’ve never worked so hard to keep a camera steady in my life.

“You’ll have to help me,” the assistant said. “We’re at T2.8 and about six feet away, and the odds that I’m going to nail focus are slim. You’ll have to help me by leaning in or out if I miss focus by an inch or two.”

“Sure, right.” I can barely hold the camera and you want me to finesse focus in 1-2″ increments by leaning in or out? I just nodded and rolled. I’m not sure anything was in focus but the actor was moving so fast I’m not sure it mattered.

Anamorphic is a great look and can be quite fun to shoot, but it’s not as simple as just throwing a slightly different lens onto the camera. Do your homework. You won’t regret it.

About the Author

Director of photography Art Adams knew he wanted to look through cameras for a living at the age of 12. After spending his teenage years shooting short films on 8mm film he ventured to Los Angeles where he earned a degree in film production and then worked on feature films, TV series, commercials and music videos as a camera assistant, operator, and DP.

Art now lives in his native San Francisco Bay Area where he shoots commercials, visual effects, virals, web banners, mobile, interactive and special venue projects. He is a regular consultant to, and trainer for, DSC Labs, and has periodically consulted for Sony, Arri, Element Labs, PRG, Aastro and Cineo Lighting. His writing has appeared in HD Video Pro, American Cinematographer, Australian Cinematographer, Camera Operator Magazine and ProVideo Coalition. He is a current member of SMPTE and the International Cinematographers Guild, and a past active member of the SOC.

Art Adams
Director of Photography
www.artadamsdp.com
Twitter: @artadams



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