Cinematography Mailing List - CML

Focus Pulling

You've probably already heard this advice vis a vis focusing, focus marks ...

* The only focus reference that is worth anything is one that doesn't move.

* Ninety percent of the time when your focus goes soft it's because you are focused too close. In other words if the operator says you are soft, best bet is to ease the focus back.

* If you get "surprised" by an actor leaning in, such as when a person leans forward to get up from a seated position, the focus adjustment is invariable one and a half feet.

* There are definitely times now-a-days when you can pull focus off a monitor, especially long lenses wide open. Useful for tight inserts (following a pen across a page), swing/shift lens shots, snorkel/borescope shots. It doesn't work if the camera zooms and you are on a dolly or jib arm/remote head, because you will not be able to interpret the video size change as being a push in (focus change) or a zoom in (no focus change).

* Focus as seen on video (video dailies!) might look O.K. but might not be good enough for the big screen. On the other hand, a shot that looks slightly soft with projected dailies might be perfectly adequate for video.

* There are times when the operator must pull his own focus. A human's 3D vision peters out after about 300 yards. With extremely long lenses (1,000mm) past 300 yards you cannot reliable distinguish where your target is in relationship to possible focus marks. You might if you have a very uncluttered vista. But if you have say a horsemen riding towards you among a bunch of brush it's almost impossible. btw. you have about 70' depth of field with a 1,000mm at 5.6 focused at 900'.

* You should know the distance between your out stretched finger tips, and half of that, etc. Finger tip distance is close to your heights.

* Always guess the distance before measuring it.

* I like to use a retractable metal tape measure for close in work and to have handy for measuring distance references in the set, ie. tables, linoleum squares, rugs, etc. I use a small 3/4" by 12 or 16' metal tape measure. People with larger hands don't mind using a 1" by 25."

* For very close up work, know the distance from the film plane to the end of the lens or matte box. Judge distance from the front of the lens/matte box to the subject and add the known distance back to the film plane.

* Don't clutter your lens with too many marks. You'll just confuse yourself.

* If you are doing a lot of long lens work in a set area (sports arena) draw a little diagram with distances indicated.

* Keep in mind that your focus distance is an arc around the camera, not a line perpendicular to the camera.

* Don't make too much of an issue about focus so that everyone starts to become hyper aware of it. They that count will start becoming paranoid and it becomes a big deal. But if you need time for marks, speak up. And speak up if you need another take. Cheaper to do it now then having to reshoot. Don't bug the operator by constantly asking him if focus was O.K. You'll have to learn to know whether you can trust him/her focus eyes.

* Always watch dailies from as far away as you can. Everything looks sharper from back there. :-)

* Always look at rushes and study your work when you have the opportunity.

* If you are putting marks on a studio follow focus marking wheel, put a reference mark on the lens barrel that corresponds to your closest focus mark. You'll need that to realign your follow focus with the lens focus barrel if they come adrift just before you roll.

* The length of your camera + mattebox/shade is a good traveling distance reference when working off of a remote head/crane arm.

* A laser pointer aimed at your track focus marks is definitely a worthwhile aid for doing critical dolly shots (and jib arm shots). Also use it to project a traveling focus point at the talents feet when doing tight dolly shots. Cinemaelectronics makes lasers that are synchronized to the camera shutter. You can have the laser dot in the shot and the camera will not record it. Great for shooting on featureless cycs and table top work. It tends to make a lot of people nervous at first because with persistence of vision the dot always looks like it's on.

* Go see the (recently released in the US) movie "Without Limits" about runner Prefontaine. Amazing 800 mm high speed running shots done with the Preston Light Ranger focusing aid. That device uses an operator (usually the 1st AC) controlled/aimed infrared laser to place focus. Note the laser aimer can't see what the long lens operator sees. They have to talk each other through the shot if there are moves to other subject matter. (The device needs a heads up video display for the laser aimer!) As a focus puller you will dream.

About having a Light Ranger.

* Before each shot, think FAST - Focus, Aperture, Shutter, Tachometer (fps).

Concentrate ... but good luck anyway ....

Mako Koiwai

Mako writes:

>You've probably already heard this advice vis a vis focusing, focus marks ...

This is some of the best information I have ever heard regarding following focus. I would add the following information learned from my mentor, Tommy Morris:

• Learn your depth of field. Know what the lenses can do. They can be your friends.

• All you really need to do your job is a ball point pen, a slate marker, a tape measure, a set of small hand tools, a Swiss army knife, some camera oil, Q-tips, a camel hair brush, a clean cotton handkerchief and a Kelly wheel. Everything else is part of your act.

• You can fit exactly one case of beer and five pounds of ice in a Mitchell 1000' mag case.

• On tricky dolly shots, keep the slate close to you. If you think you are blowing the focus, discreetly kick the slate of the dolly and let the sound man cut the shot. It only works once per show.;-))


Ed Colman

Mako your advice was superb ... there are just two tiny things I would like to add

There will come a moment when the shot "can't" be done. Deciding when this is is hard you have to take lots of factors into account. For instance I did a job (a Super16 commercial) shot in someone's living room. The camera was hand held the stop was T1.3 on a 50mm prime. The actor was working without marks and the operator was moving around as well. The room was only about 12' square and was very crowded Distances were 4'6" to 6' and the director wanted it constantly in focus. What I should have done was to (politely) put my foot down and try to get the DP to either raise the light level, stand still (just let the actor do the moving) or move a lot of people around so I could see both the camera and the actor at the same time. As it happened we spent an hour and a lot of film trying to get it right. This makes me a dickhead. Yes you are the focus puller, under normal circumstances there is no reason for you to even question the setup but sometimes it has to happen. The usual response (not from the operator from the director or production) is but so and so did it on such and such a production. I have been exceedingly lucky to have always worked with wonderful DP's when the going gets tough like this. Remember there is no such thing as "Impossible" just logistically impossible. This job would have been easily possible in a studio with removable walls and lots of space were I could see everything .

When I first started focus pulling I used to practice with radio controlled cars on a tabletop. I had a friend who wanted to operate a geared head and we would both practice with his girlfriend operating the radio controlled car (which I had pasted siemens stars on). Start with a 50mm lens at T1.3 then later move to a 100mm. Practice like this gives you a certain fluidity of action and concentration. Also it inspires confidence in your own abilities. How much better to have an operator shout SOFT at you in your own home when you know he is your friend and that nothing is lost than on a film set with 50 people watching what you are doing and cursing every time you get it wrong ?

ALWAYS be nice to your loader :) (be nice to everyone in fact)

Justin Pentecost

A few minor additions to Mako's Detailed list

I always put the mark to sync up the follow focus and the lens at the infinity mark.

At frequent intervals check your cloth measure against a steel tape measure, sometimes the cloth ones can stretch.

Never measure distance to a person's face with a steel tape measure. This makes the many thousand dollar a day models, and the D.P. very Nervous.

Steven ( I cut an actors hand accidentally with a steel tape measure once, the make up person got all the credit though) Gladstone

• Remember that focus carries 2/3 back from the point of focus and 1/3 in front. If you are in doubt, cheat an inch or two forward. (Of course remembering Mako's caveat about close focus).

• Pulling focus on moving shots has as much to do with music and rhythm as anything. The rehearsals are very important (when available) to find the rhythm of the shot, and once you and the operator and the actor are locked in, making the shot is much easier. When you are told to 'shoot the rehearsal' it's not a rehearsal any more.

• A good dolly grip is worth his weight in gold. (Not always an insignificant amount). He can tell you if he is an inch or two off his mark, and you can sometimes compensate. You should have your own dolly marks anyway so you should already know if he has missed. He can also totally bone you.

• Treat everyone nicely. The loader, the operator, the PA's, everyone. You never know if the guy/gal filling the coolers one day won't be producing your next project.

• We are all only flesh and blood. There are some shots that are 'logistically impossible'. We can only do our best. No one can be perfect 100% of the time.

• It helps if your DP supports you. I was doing a shot many years ago on a table top toy shoot. We were following these one inch long cars blown around by streams of air. Long end of the zoom, plus 2 diopter, the whole thing. I was having a tough time keeping it all sharp. The crew and AD started complaining. The Cameraman, God bless him, stopped the show, looked at everyone and asked if any one else thought they could do my job any better. Everybody shut up and we got the shot.

• Regarding TC's story: I think that is the exception rather than the rule. You can't really do anything about ignorance except try to educate people. Anyone who has spent more than five minutes behind a camera knows what a difficult, nerve racking, unsung job the Focus Puller has. If the DP doesn't respect this, there is nothing to do but try to work with him/her as long as you are able, but sometimes, we do have to stand up for ourselves. Try not to burn the bridge though. (Well, you may have to burn it, try not to dynamite it.) Remember, it is a very small community.

• Most importantly, try to have fun with it. When it is all going smoothly, you know if you nailed the shot or not, and you don't have to ask the operator if it was sharp. When he starts asking you if it was sharp, you have arrived.

-- -- Ed Colman

For instance I did a job (a Super16 commercial) shot in someone's living room. The camera was hand held the stop was T1.3 on a 50mm prime. The actor was working without marks and the operator was moving around as well. The room was only about 12' square and was very crowded Distances were 4'6" to 6' and the director wanted it constantly in focus.

Interesting problem. One solution would have been to use a thin carbon fishing rod stuck on top of the camera with its tip at 4 feet or even 5 feet if possible. This is assuming that the operator is standing and the rod doesn't "interfere" with the lighting. With this rod giving a 4 feet reading and putting a bright mark at 3 feet, one can "see" a lot more easily the finer distinctions between let's say 4'3 and 4'9. A 2nd assistant with a fine eye for distances can also help in these situations by giving you some cues over talkies with headsets

Over the years I have collected different kinds of fishing rods (Mitchell are my favorite) and rubber sticks and find them a lot more handy than lasers because when stuck to the camera they give me a constant reference in space and are usually a lot closer to my field of vision which is generally the actor's face. I use them when markings are not possible or because I know I will not have the time to read them. Generally these are shoulder shots or fast tracking shots with the talent moving close in to the camera at one point. Finally these rods, if properly positioned, can prevent the actors from moving in too close to the camera.

On some occasions however, these rods can upset either the actors or the director, so I use them care and take them off the camera between takes.

Leo Mac Dougall

A focus-pulling mantra that I think holds true:

"You're only as good as your operator"

And it goes the other way as well: the operator is only as good as the focus puller.

Lil' Focus tricks to humbly add to Mako's:

"Finger marks": When the subject approaches quickly, put your thumb on the wheel so that it stops in the 12 o'clock position when the lens gets to what you expect to be the closest mark, say 3 feet. That way you can keep sighting the fast approaching object but can feel where 3 feet is via thumb and finger position. I would also have a finger at 4 or 5 feet. You still have to look at the lens to fine-tune, but it can really help "feel" the distances.

Depth-of-Field charts on big primes: This works great on Panavision primes since they're nice and big. Put tiny little depth-of field marks on the lens (above and below the focus index mark). Use colored tape to color-code them. Just 2-3 stops worth, and different for each lens depending on focal length. On a 200mm you might only have 5.6, 8 and 11 at the most. On a 17mm you might have 2.8, 4 and 5.6 (anything more wraps around the other side of the barrel where you can no longer see it). Great for really quick judgments on focus splits...when doing hand-held with method actors or other ridiculously blocked and unrehearsed scenes. A thankless skill. Keep in mind that it's not THAT accurate on all primes, since they are engraved to match any mechanical discrepancies that throw the focus scale out of perfect, geometric progression. In my experience they're usually really close.

Put something soft on the end of your steel-tape measure (such as a tiny boxing-glove that normally sells as a keychain). It puts the actor at ease when it zips out within inches of their faces. Sometimes, you really should not use it, but it is a great tool 99% of the time.

Enjoy the time that you would rather pull focus without marks. Set goals for yourself such as: I will not use a tape on lenses shorter than 50mm (unless the subject is really close). Checking your work in dailies is 50% of the job. You will no doubt be a good focus puller when you enjoy this aspect, but don't get too cocky either.

Don't forget about the speed & timing of the pull. It's not just about getting to the right marks and achieving sharpness, it's how one arrives there. Fast, jerky focus pulls can look really terrible. Go to dailies and see how timing your focus-pull with a head turn or a camera movement can completely disguise it. Your work should be sharp, but invisible in it's means.

Statement of the obvious: Work quietly whenever possible. Being a camera assistant affords you a position very close to the camera, which is also where the DP, Director hang out and need to converse. Do your job as surreptitiously as possible and eavesdrop on what's happening. If a backlight is being put in, go ahead and put on an eyebrow now and re-balance the camera before the light flares the lens...that sort of thing.

Mark Doering-Powell

Great to see all of the other focusing advice and tips!

* The best thing is just getting lucky, which after awhile does happen. <g> I got to spend most of today sitting under a perfect warm autumn sun next to the San Francisco bay, turning a locked off Platinum with a 10mm lens on remotely. While the director and the agency pondered the variables in our test, the DP and I got to watch a great air show (including the Navy Blue Angels) which just happened to be occurring right in front of us over a sail boat speckled bay.

Sorry - it was just one of those great pay back days ......

I forgot to mention, yes I do have the end of my steel tape measure covered with a soft white square with a red X on it. I always try to measure off to the side of the actors face and I do pay great attention to what I'm doing when I stick that tape measure out. I've noticed more actors will now actually take the end of the tape measure and bring it next to their eyes. I think we've actually started to train them ... <s>

Concerning Justin's focus horror story in the small room ...

I was working with a new (to me) D.P when he asked me to put the 135 on the camera that I had been asked to set-up hand-held. I knew we were going to be wide open, T2.1, and I was wondering how long I was going to last. I must have been radiating fear because he quickly said "Oh, don't worry, I do my own hand held follow focusing."


He showed me that he had a special way of setting up the shoulder rig for his BL4 that allowed him to support the cameras weight plus finger the follow focus whip. (He palmed the left hand support so that his fingers were free to twiddle the whip.) He was magnificent in following the action and keeping things in focus. Turns out that he came from a documentary background and had always done his own focusing. His "special" trick was that instead of trying to always follow focus with long lens he would move with the subject matter. It didn't bother me that I was essentially a highly paid loader that day! <g>

I think I've seen almost as many operators on movies get into trouble because of a high percentage of out of focus shots as focus pullers. The directors were incredulous that the operators either hadn't made it clear enough that there were focus problems or hadn't tried to help more with focus, ie. the shots started out of focus meaning that the operator hadn't handed off the focus to the AC with a "it's sharp - here!"

I know that in Hollywood more and more focus pullers are using remote follow focus systems that allow them to situate themselves where ever it's advantages (and not just for handheld or jib arm work). Some people find they can be more accurate judging distance by being more at right angles to the camera and subject matter. Band Pro (and soon Preston) offer simpler, lighter single channel wireless follow focus options.

I recently had to do an unrehersable sequence with little kids and a mom sitting and playing and running around a picnic setting on a beach at twilight wide open, 1.3 with a 65mm. The camera was on a remote head on a telescoping arm. The Dp/operator talked the crane grips through the shots via headsets. We were all over the place, continuously moving, and including inserts of toes wiggling in the sand, etc. No time, no way to ask for focus marks. I'd say at least 95% of the footage was usable focus-wise. The fact that we were wide open made focusing pretty easy! The director was very happy.

For the ultimate on everything about focusing, see Fritz Hershey's book "Optics and Focus" (Focal Press) for camera assistants. 280+ pages, from basics to very technical to Zen. (Even) I haven't been able to work my way through it. <s>

The very best general book on assisting, that I think everyone could learn something from is Doug Hart's The Camera Assistant, also Focal Press. Doug was Gordon Willis AC for ten years, besides working with other top Dp's.

I remember some test scores from when I was a kid. I was only average, but I scored very high in knowing where and how to find information! But honestly, I have managed to absorb some of what I've read .... :-)

... Mako - CML is all about sharing .... anybody want to "share" my ..., oh oh, almost forgot the rental houses are listening ..Koiwai.

RE: more Focusing ...

Especially in light of the recent discussion concerning the many soft shots in "What Dreams My Come," I want to let everyone know what we did on our recent Disney World commercial in Orlando.

We had some night exterior shots over water at the Epcot Center using a 300mm Nikkor F/2.0. (Note that every 300mm Nikkor that I've ever seen adapted for motion picture use has been a T2.3, 2.4, as measured on the light transmission devices at various rental houses. If you look through that lens and open up the aperture, you will see that at some point the iris disappears behind a restriction. If you check the aperture ring you'll find that that happens around t2.3, 2.4. Opening the aperture any further has no effect.)

The camera was on the shore; we were shooting a family at the back of a boat that was moving away from us. I simply follow focused while looking through the eyepiece while our DP operated off of a monitor. Another DP that I work with also "allows" me to do this since he actually prefers to operate off of a monitor. I'm finding that at least in commercials more and more of the operating, especially jib arm and low angle hand held work (of course remote head work) is being done off of monitors. For one thing, the CEI 4 & 5 taps (Arri and Panavision) and the 435/535(new) IVS taps are good enough to allow that.

I did a Japanese Honda spot a few months ago where the Japanese DP probably looked through the camera eyepiece twice in three days of exterior work. He loved using my 5" TransVideo on-board monitor. (I thought the on-board monitor was suppose to be for my benefit :-)

Although I understand the position that the focus pullers were in on "What Dreams May Come" (see my message after talking with them from a couple of weeks ago) I can't help but think that at least on some of those stationary close-ups, focus could have been improved by looking at a monitor.

I remember doing a shot where we followed the feet of a rodeo cowboy all around the field with a 600mm wide open. We got great shots that I seriously doubt I could have done without focusing off of a monitor. I find it especially easy with long lenses and no depth of field (obviously!). And we were able to do it "right now" with no waiting to get focus marks or set-up/calibrate/rent a Preston Light Ranger, or restricting the talents actions.

Monitor focusing can also work great when shooting inserts, following a pen across the page, etc.

Another way of using a monitor to do focus is to note size on the monitor with a focus distance/mark. Full head is one distance, half a head another distance, etc.

These techniques are not a way out of being able to do follow focusing the old fashion way but are often a tool to use if pressed for time/losing the light or for unusual conditions like shooting across water, (PanaTape is only good to about 18/19 feet). It sure beats the 3,000 feet of almost entirely unusable footage that I once saw from our "B" camera on a boat to boat sequence on a feature. Btw. it was the operator that caught hell in that incident. He didn't report the problems and he never seemed to grab the focus, at least at the beginning of the shot to give the focus puller a starting point.

Another excellent but slightly time and manpower consuming technique to guarantee usable long lens focus is the side sighting method.

A sighting mechanism is situated 90 degrees to the line of action (say a car coming towards the camera). Inexpensive rifle scopes can be purchased for $30, but you can also use a "C" stand arm arrangement. One needs to fashion a marking disk and a pointer. I used wire for a pointer and paper plates for a disk through which my tripod/"C" stand penetrated.

Usually utilizing a walkie talkie for communicating, the sighting device is aimed at a point where the object will be (stand-in, PA or actual object) while the focus puller eye focuses on the same object, and a mark is made on the disk opposite the pointer and on the lens/follow focus. You do this until you have all of the marks you think you need.

During the shot, one person must follow the subject matter with the sighting device, another reads off the numbered marks on the sighting marking disk and relays them to the focus puller who just matches the numbers. Of course some form of anticipation must be built in.

The good thing about this method is that you don't have to have actual physical marks along/next to the pathway that the subject matter is following. This means this method can be used for shooting over water or through the air. Sometimes the sighting mechanism can't be 90 degrees to the subject but it will still work. Keep the pointer fairly long so that the marks aren't too close together.

Some AC's have made very professional looking rigs with Delron or nylon marking disks, etc. If anyone is interested I can get you in touch with someone who has made up a very nice rig.

I personally don't use this method since it's usually too time and manpower consuming. I made it up for a shoot where I was warned that we would have a lot of long lens at the camera work. It turned out that every shot was in a hallway or tunnel where there was not room off to the side! <S>

I did have my rig with me for a specific job where we were going to be following a car coming right at us with the Clairmont 1,000mm T4.5 lens on a dry lake bed. I explained the rig to the out of town/new DP that I was working with. He had never shot a car commercial. He said no we won't need to use that. I don't want to take the time; I can do the focus myself.

_Part way_ through the second take he let go of the focus knob and told me that I better do the focus myself!!! We had a poor video tap (not one from Clairmont! :-) and poor monitors. We ended up taking the time to set up some cones for focusing marks ...

Enough to make one buy a camera and call oneself a DP!

... Mako Koiwai

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