Remote Focusing

[Ross "James" Greenash]

Hello,
I recently bought an EX1 but quickly returned it when I realized that I'd need to have a separate adapter to remotely change the focus. I thought I had read that RED allowed electronic remote focusing, but, in reading more about the Scarlet, that doesn't seem to be the case - I'd still need an adapter, as I would have for the EX1. Is this true? What, if any, of the prosumer cameras similar to the EX1 and Scarlet, have this feature? It seems like this would be a basic requirement.
Thanks,
-Ross

 

[Craig Parkes]

Why would it be a basic requirement!? What exactly are you doing that requires remote focusing that isn't specialist in some way shape or form?

 

[Ross "James" Greenash]

For two reasons:
1) If you want to get a moving shot with a shallow DOF, then it would be a requirement, no? Otherwise, you have to stay the same distance from your subject to keep them in focus.
2) If you want to shift the focus from one person in the frame to another, you need some sort of focus control that doesn't involve manually turning the focus ring, otherwise you have the potential to nudge the camera and cause bumpiness in the shot.
Those are two kinds of shots that I consider critical for a higher-end camera use, namely for making film-quality films.
Am I missing something here or is this just not a common thing on prosumer cameras? Or do people just accept the fact that they'll need an adapter for focus control?
I see products like the Varizoom which can control Canon XH cameras' focus and I wonder where this functionality is in the other high end products like RED and the EX1.

 

[Ian B. Johnson]

http://reduser.net/forum/showpost.php?p=445538&postcount=8

 

[Ross "James" Greenash]

That's pretty cool but I'd love to see it documented somewhere besides the forums - is that functionality embedded in one of the other RED products? What about just an electronic focus control? I'm thinking more about having that so I can do the shooting and the focusing myself, without needing someone else dedicated to focusing.

 

[Ian B. Johnson]

I'd say Jarred's word is pretty official, though I agree- I'd love to see some more details about the feature.

 

[Dan Finlayson]

For two reasons:
1) If you want to get a moving shot with a shallow DOF, then it would be a requirement, no? Otherwise, you have to stay the same distance from your subject to keep them in focus.
2) If you want to shift the focus from one person in the frame to another, you need some sort of focus control that doesn't involve manually turning the focus ring, otherwise you have the potential to nudge the camera and cause bumpiness in the shot.
Those are two kinds of shots that I consider critical for a higher-end camera use, namely for making film-quality films.
Am I missing something here or is this just not a common thing on prosumer cameras? Or do people just accept the fact that they'll need an adapter for focus control?
I see products like the Varizoom which can control Canon XH cameras' focus and I wonder where this functionality is in the other high end products like RED and the EX1.

This is not a basic feature -- I dont know any camera that has it built in (because most people forgo remote focus for 90% of shots). If you dont want the camera to move, lock the tripod or rely on the weight of the camera to smooth the motion (with a Red One, for example, the rig will be sufficiently heavy to prevent small vibrations in most cases)

 

[Scott C.]

I see products like the Varizoom which can control Canon XH cameras' focus and I wonder where this functionality is in the other high end products like RED and the EX1.

You returned a prosumer camera because it didn't include remote follow focus in the box? While there are products which allow you to add follow focus to most cams prosumer and above, I don't know of any that come with it as a part of the basic package... so yeah, I think you are missing something. Remote functionality on many prosumer cameras comes via the LANC port. If your camera has one, then you can likely find a remote focus control.

Where is the Varizoom remote focus for the EX-!? It is here:



Perhaps you should have posed your question to the Varizoom people before you returned your camera.

1) If you want to get a moving shot with a shallow DOF, then it would be a requirement, no? Otherwise, you have to stay the same distance from your subject to keep them in focus.

For the vast majority of the time I utilize limited DoF in close up shots, so it is relatively minor to impose a limit on movement in that type of situation. The rationale is that we are using DoF to focus the viewer's attention on smaller details, and those tend to subtle expressions, small gestures or complex objects. In those situations large movements are usually more of a distraction from what is important in the shot, and limiting that movement has the dual benefit of helping to focus attention, as well as making your job easier... it's a win win.

If you make certain that your background is no brighter than your subject, then the AF is likely to do a fine job with fewer takes and headaches than manual focus when shooting shallow.

2) If you want to shift the focus from one person in the frame to another, you need some sort of focus control that doesn't involve manually turning the focus ring, otherwise you have the potential to nudge the camera and cause bumpiness in the shot.

That is possible and even likely, but not necessarily true. It can be done.

Am I missing something here or is this just not a common thing on prosumer cameras? Or do people just accept the fact that they'll need an adapter for focus control?

Most prosumer cameras that I am aware of do have a LANC port, so you can add remote focus, as previously mentioned.

It isn't really typical of consumers to be making those kinds of shots. I think the goal in designing a consumer system is to make it easier for inexperienced shooters to achieve stable, focused shots on a budget with a small form factor. Deep focus is one way to accomplish that goal, so it would be counter productive to use large, expensive sensors in a consumer camera.

Folks who do wish to create those types of shots are generally more sophisticated than Uncle Bob and Soccer Mom. They understand that what they are attempting to do requires more specialized tools, so adding follow focus to the camera for them, isn't so big an obstacle.

 

[Aaron Newsome]

I'm still waiting for someone to post a pro or prosumer camera that comes with a built in remote follow focus as part of a basic package. I'm thinking such a thing does not exist.

 

[Michael Panfeld]

James: we can talk in class tomorrow, but let me say that if you are going to be using a 35mm adapter in front of the EX1 (or whatever you buy), then the cam's focus becomes the adapter's backfocus. Once it is set, it is locked (humidity, temperature changes aside). The focus (and the shallow DOF) then comes from the 35mm lens. An add-on follow focus can be manual, wired, or wireless. No adapter includes a FF in a basic package. The cheapest manual FF costs a few hundred and can go up to $2K. The Varizoom wired system noted above costs $700 for the electronic version plus a few hundred more for a rod support system. A wireless system starts at $2500 (The just now appearing units from Viewfactor) up to the $10,000+ for the Arri and other high end systems.

If you are going the 35mm adapter route, you not only will need a FF, but another person as well. The only way for you to avoid adding a focus puller to the shooting team is if the cam is locked down on a tripod or if the FF has some kind of mechanical stops that you can feel for while you are handholding the cam. Otherwise, the focus marks can't be seen by you if you are also watching the framing. You could try to do it by sight, but unless you are the Tiger Woods of focus pulling, the resulting focus rack will look amatuerish and, most likely, will not be in focus. The Varizoom allows 4 preprogrammed focus points, which is great for sets where you can block the movements. However, if you are doing steadycam work, you are still flying by wire.

If you are skipping the 35mm adapter, you can partially achieve a shallow DOF by "cheating" the lens on a small sensor cam. But that means you need to stand far away from the subject and zoom in. The longer focal length will yield more DOF and be controllable using cam's manual focus but it will be at the expense of aperture (i.e., you will need more light) and the limitations/quality of the cam's manual focus controls; which may not be placed in an ideal position. That said, you still might miss a rack focus since you will be "eyeballing" (i.e., user error). Bottom line is, until you get to 2/3" sensor size and up, you are not going to get a whole lot of the shallow DOF, and what you do get will be at a sacrifice.

There is no problem that can't be fixed by throwing a lot of money at it. Maintaining focus on continually moving cams and subjects while maintaining a shallow DOF is one of them.

I should be getting my wireless FF from Viewfactor this month (cough) and my rental business is starting this month as well, so you can try it out before you buy.

Cheers

 

[Michael Panfeld]

James: there are systems that would allow autofusing, but you are looking at $25K or more. There is a system made by C-Motion. There is also the Cine Tape that can by used with the ARRI follow focus system in either manual or automatic mode. I know that you don't want to hear about a $25 system, but to be honest, there is absolutely no reason why someone can't design a DIY system for under $5K (and that includes a Viewfactor wireless FF system at $2500). In fact, the guy behind Viewfactor posted about a theoretical system on this forum over two years ago: http://reduser.net/forum/showthread.php?t=1059

You're an electrical engineer. I will soon have my Viewfactor wireless FF, wanna collaborate?

 

[Ross "James" Greenash]

Mike,
I generally use filmmaking to do something other than electrical engineering (i.e. something creative), but let's talk about what would need to be done to make this cheaper than $25k in class