Autofocus

[damonbots]

Yeah, I know... "real cinema cameras don't have autofocus and they never will".

Can you imagine if Jim said "an inexpensive 4K camera doesn't exist and it never will"?

I just hate the word "never" and I especially dislike close-mindedness.
I'm just wondering if the RED team would ever be receptive to the idea of implementing some sort of autofocus on the RED ONE in the future. The RED camera is based on revolutionary ideas. Why stop now? I bet Graeme could design one hell of a focus tracking algorithm.

[Michael Mann]

The RED camera is based on revolutionary ideas. Why stop now? I bet Graeme could design one hell of a focus tracking algorithm.
I absolutely agree! There is no reason at all why an (optional!) intelligent AF should not be part of a professional camera.

[Stuart English]

O.K I'm game to continue this discussion - focus on what?

[PaulClements]

Ok Stuart for a bit of fun, here goes. Mind you I don't have a clue about this stuff so take it with a pinch of salt if you will (Before you tear it apart) :)

What you would need:


Motorized follow focus or lens that can be controlled by the camera
Device for accurately obtaining the distance of objects away from the camera (If not available through an intelligent lens or via the sensor).
Software to detect the sharpness of and around objects and distinguish patterns in colour and shapes (Magic Focus?)
Database of lens settings

Step 1: Sync the lens/ff for the scene
Step 2: Choose an object or person to maintain focus with (Physically point using a cross hair perhaps)
Step 3: Set the auto refocus time (If an object moves in front of the object you are focusing on how long before the camera should refocus, if at all).

AND BEGIN SHOOTING

As the object, person or camera moves, the center of the sharpness of and around that object maintains the area on the sensor that requires focusing, it captures the distance that object is away from the camera. As the object moves toward or away from the camera it takes the distance and recalculates the focus according to the lens settings and distance for the person or object.

N.B. If an object should move infront of the lens and then move away and the object previously being focussed on has moved to a different focal point the software detecting sharpness would have to be intelligent enough to guess the most likely source for refocussing on by using the colour, shapes, relative distance and sharpness to make an informed guess.

[damonbots]

O.K I'm game to continue this discussion - focus on what?

Well, I'm hoping to focus on an icy cold Newcastle when I get off work, but
in regards to my original comment, I guess I'm thinking about something similar to the AI servo AF mode on my DSLR. I imagine this would complicate things significantly, but I'm sure quite a few folks could justify the added expense, especially if the feature was as revolutionary as the camera is now.

Edit: Paul, that's exactly what I was thinking. Nice!

[Martin Drew]

Okay. I can see a place for auto focus, firstly as an off shot tool for helping to mark focus positions. In theory this could be more accurate than a tape measure because focusing would be part of a feedback loop, especially valid if using stills lenses for example. Secondly for very tricky tracking shots eg keeping focus on someone as they run towards the camera, while maintaining minimal DOF.

You would require a means to input the focus target, this could be a separate device operated by a focus puller, maybe a touch sensitive screen or a position sensing controller that could be moved about.

I never have a problem positioning my stills camera in order to define a focus target so maybe there could be a target definition interface which works in a similar way for the camera operator to use, for example a collar on the viewfinder which can be moved by your left hand. Your hand would rest against your cheek, in the same way it might if you were holding a telescope. small positional movements of that hand would move the collar and there would be a positional relationship between the collar and an onscreen focus target. To define the target you would press a button on the collar with your thumb. The camera would only autofocus while the thumb button was pressed. Don't know how practical this would be ergonomically, just thinking out loud.

M

[Clayton Harper]

If the camera assistant could paint the target/subject with a "pointer" and have that info fed into the red focus motor, that would be insanely great.

OR, in the VF there could be focus areas like the ones you see in your digital SLR auto focus and you could somehow use those to target the focus. Martin is onto something there.

[miskamagic]

If such a thing does not already exist, what I always thought would be cool would be to have a 'key' that you attach to talent or an object, like a small clip that contains a tranceiver. Wherever that key went, the autofocus system would keep focus on it. It would have to be radio activated, not line of sight like lasers or IR, and I have no idea how the math/geometry would work since of course its not a simple thing of perpendicular distance to the lens. If the keyed object is off to one side of the lens, its now at a diagonal from the sensing device and its absolute distance from the lens is different from distance to its plane of focus.

Of course this wouldn't be useful in all focus pulling situations, but it would make certain shots much easier if not possible in the first place. Also you could do a lot of cool special shots, like imagine putting the key in a soccer ball and then kicking it around, everywhere it goes it stays in focus, yet swimming in a blurred environment around it.

You could also expand the system to use multiple keys and have some facility to tell the system to 'rack focus from key A to key B using X amount of speed doing it', use exponentinal vs linear fades from one focus point to another, etc.

-miska

[LighthouseMEdia]

Okay interesting point guys but a few questions.
1. so you want a laser on your subject?
2. what about when their torso where the transmitter or laser is hitting
is in one place and they lean in 6 inches on DOF shot of just inches and you want only their eyes sharp?

Don't get me wrong, I think it is a great idea just not sure on the practicality of it.

[zoltan77]

I was thinking of something incredibly small, like RFID sensors (no idea if the technology would actually allow you to do something like this though).

RFID is something like the size of a head of a pin. Imagine you peel off a disposaple sensor, type/scan its unique bar code into the autofocus system, conceal sensor under makeup on the other side of talent's nose, in an eyebrow, etc. wherever you desire exact plane of focus to be. When you're done with the shot, throw away the sensor, repeat for another shot.

-miska

[Greg Voevodsky]

i would simply take the autofocus from a still camera, combine it with a small x-box analog joystick mounted on the handle with a nice RED dot (positioned by the joystick - like a good sniper site in Halo) and then keep the red dot on the target or what ever you want to rack to.

Still photographers embraced auto focus, (even pros), and when things get very tough so does Hollywood use a laser system... You try rack focusing a dragster coming out you at 300mph with an 800mm lense...

You don't see the military playing games with targets, they have auto tracking, auto focus, etc... why Hollywood wants to hold out to soft focus that I see way too much in featured films than it should be - is amazing. But, I;d guess it may be job and union related rather than having a robot or computer replace it. What's going to happen to the poor 2nd AC film loaders and unloaders when we can film all day on 1 drive and download in 5 minutes. What about the PA to drive 40 minutes to drop off the film at Fotochem?!! Game over man.. Game over. :-)

It's probably why AVID was built by computer engineers rather than film editors.

[Martin Drew]

I think you are basically right Greg. The issue with motion cameras isn't the autofocus itself it is defining the target. I do believe it is do-able, and I can see real benefits. The biggest problem is probably the notion that motion autofocus is only for cheapo camcorders. I could imagine some kind of system which combines auto tracking with a direct target painting input

M

[Matthew Rogers]

I was thinking of something incredibly small, like RFID sensors (no idea if the technology would actually allow you to do something like this though).

RFID is something like the size of a head of a pin. Imagine you peel off a disposaple sensor, type/scan its unique bar code into the autofocus system, conceal sensor under makeup on the other side of talent's nose, in an eyebrow, etc. wherever you desire exact plane of focus to be. When you're done with the shot, throw away the sensor, repeat for another shot.


Hey, that was my idea!;) When I first started reading this thread I was thinking about some kinda transmitter that could tell the lens where it was for focus. To me an RFID would be ideal for size (I believe they have to be within 1ft of the scanner to be read though...) You could program the lens for upto say 10 RFID's and through a touch screen the focus puller could select which RFID was supposed to be in focus. If you needed to rack focus you could set in the computer how fast to rack and then when you selected the next RFID it would rack at the pre-selected speed.

Even a system with transmitters the size of wireless mic packs would be fine as far as I'm concerned. I can hide those on most actors fairly well (would still have to manually focus those bikini scenes!)

I know this would never work for ENG style shooting, but there are plenty of shoots with actors that this would be killer for (especially studio shoots that do not have a focus puller.)

I am amazed that with all the computer and wireless technology that we are still having to do some things manually. The technology is there. It's just convincing a company that such a product is needed (and hope they make it reasonably priced!)

Matthew

[Hrvoje Simic]

As far as defining the target goes, using hidden sensors on a subject to me seems like the best solution (although I have no technical knowledge in this department).

A person can carry the sensor hidden under the clothes, and in scenes with not so shallow DOF this might work. This could also be used with shooting vehicles.

Programmable offset option would be really useful.

For the shots with extremely shallow DOF sensor location could be a reference for additional manual focusing within the selective focus range. In this case focus knob turn/ratio would cover only the desired focus range (for example 5"+/- from the sensor).
This would be a kind of semi-automatic focus system.

The automation would take care of "rough" focus, while detailed focusing would be done manually.

[Matt Uhry]

...And all the operators could be replaced by robots running algorithms that kept subjects nicely framed with a carefully calculated amount of negative space.

Focus is creative. It's best done by a human. The style of auto focus in the best DSLRS might be usefull for a few kinds of shots, but for the majority of work it is far from being able to replace a gifted 1st AC. Besides, who is going to bring you coffee and snacks, your pet robot focus drone?

Innovation is very welcome, but I'd encourage newcomers to find out how all this film set stuff actually works before trying to reinvent it.

Matt Uhry
www.mattuhry.com

[Ace]

It would be cool if you say, point to the target and tap the focus button, and the focus would ease in at a specified speed and using ease in and ease out acceleration curves. Would bring a whole new methodology to motorised focus which wouldnt look as artificial as tradition autofocus methods.

[Milan Nikolic]

It is great idea to have auto focus on the RED pocket camera given the size of it (you can put it the pocket, lens in the other) and the gun and run way of shooting. I would like to have in this camera 12P photo camera - this way all my needs would be satisfied if this camera would do at least 2K video. This also ask for auto focus.

[Martin Drew]

Hey Matt, we are just kicking ideas around here, read the first few posts at the beginning of the thread. Besides... you hurt my coffee droids feelings.

[Hrvoje Simic]

Since people tend to jump to conclusions I'll point out that I don't think automatic focusing should totally replace manual control.
However.......it could really help in many situations, through a form of semi-automation suggested in my previous post.

I doubt people are throwing ideas here because they are lazy to focus manually, or they are trying to reinvent anything.

Constructive criticism is very welcome, but I'd encourage people to find out about the power of idea in general before trying to criticize it.

[P Andersson]

If it was available people could simply choose to use it or not.

It could function in multiple ways, one would be like regular autofocus does, a second could follow an object like a contact lens or other "key" with some kind of transmitter or specially painted color, another way would be with a laser pointer or such device. Of course you would always be able to manually override it even in the middle of a shot.

Optical image stabilization is another great tool that could be helpful sometimes.

[DSH]

Think all these ideas sound great in principle, but I think ignore the 35mm depth of field issue. When doing closeups, if you are wide open you can be having a discussion as to which eye you want sharp.

If you're MAC based have a play with this widget: http://www.fuerstentum.net/Widget/index.html

Being able to anticipate, the lean forward, a head turn, is something only a focus puller can do. I've rumbled on before about the depth of field issue, but it is something you need to think about in terms of lighting levels and shooting stop. My approach towards the RED camera is that if you are shooting 4k, its not a run and gun camera. Sure exterior, but night shoots, interiors you might need to think again.

[Hrvoje Simic]

Think all these ideas sound great in principle, but I think ignore the 35mm depth of field issue. When doing closeups, if you are wide open you can be having a discussion as to which eye you want sharp.

If you're MAC based have a play with this widget: http://www.fuerstentum.net/Widget/index.html

Being able to anticipate, the lean forward, a head turn, is something only a focus puller can do. I've rumbled on before about the depth of field issue, but it is something you need to think about in terms of lighting levels and shooting stop. My approach towards the RED camera is that if you are shooting 4k, its not a run and gun camera. Sure exterior, but night shoots, interiors you might need to think again.

I agree. That's why I suggested a semi-automated system.

[miskamagic]

Hey, that was my idea!;)

Matthew

If I wasn't busy with other work, I'd say lets get some money and engineers together and make it happen...:)

I completely agree that this would never be a replacement for top notch AC's. My thinking was that this would be more of a specialtly application for shots that would be extrememly difficult to impossible to pull off with a focus puller - FX shots, etc. Think of moco vs having an operator. Moco can't replace a creative and intuitive operator, but its opened up a whole new realm of possibilities in shot making combined with FX and compositing.

-m

[Alexander Black]

Sure, you just need some ir reflective makeup (or the weird blacklight stuff from mova, if I remember right), a little flasher and something which can measure distance for a small wavelength range in the EM spectrum. Easy.

So, now that you have that, you can have the makeup... engineered... to reflect only very specific wavelength ranges and use 4-5 emitters so you can have.. 5 buttons on the remote FF.

Focus on subject 1, 4, 2, 4, 2, 4, 1, 5.

I think the best thing is an ultrasonic cinetape and experience.

But the above would be cool if anyone does it - especially with invisible makeup.

And people are working on it: http://www.mova.com/pages/whitepaper.html

[Clint Johnson]

pattern recognition technology is advancing fast and while this is a bad thing for privacy and freedom, it will have applications in cinematography. Just at a cursory look, it seems that to re-purpose this technology would be an engineering task rather than a big R&D push.

So maybe the Red Two will recognize you cast and understand when you instruct it to keep Angelina Jolie's left eye in focus throughout the shot... or that you want it to rack focus to Morgan Freeman when he begins to speak... and then rack aperture to get them both when they begin to overlap dialogue.

Then there is eye tracking where you can override the Red Two's task list with a press of a button while you look at what you want in focus. Red Two will then keep that object in focus until told otherwise. You could override the decision list on the fly by looking at Angelina Jolie to capture her reaction to Morgan's dialogue... although this might piss off your director if he doesn't trust you enough to improvise.

I'm pretty sure that we are heading towards pattern recognition and tracking the camera operator's eye as the primary means of focusing cameras. The DoP and the camera operator are still in charge of the decisions about what is in focus and when, just we would be telling the camera rather than the AC.

[Steve Gibby]

Tons of S35mm use of RED will be at mid to deep DOF. Many EFP genres that RED will be used in require only occasional shallow DOF for creative b-roll. Autofocus would be especially useful in those EFP genres: sports, nature, documentaries, stock footage, run ‘n gun, business media, etc. Shallow DOF narrative cinema is but one of the many genres that RED One will be used for. Across the broad range of genre and sub-genre productions enabled by RED One there are times/genres where an all-manual workflow is necessary. There are also times/genres where accurate autofocus would enhance the field workflow: mid to deep DOF 35mm, 2k, 1080p, and 720p EFP production, etc.

Autofocus would make an already flexible camera system even more flexible in workflow - and no, autofocus isn't something just used by prosumers and beginners. It's used extensively by pros in non-hardlined EFP production when a genre and workflow call for it, in many single person field workflows where operators must control all camera functions themselves. Experienced shooters understand its limitations, when to use it, and when to stay in an all-manual configuration.