Scarlet Electronic Rack Focus Request...

[Rick Burnett]

So today we were out doing some test shooting with a 7D and got into a discussion on rack focus with the Scarlet and the fact the follow focus can be run electronically (from what I have read). We did a little brainstorming, and I thought I'd at least provide back to the community what we though would be good ideas and see what anyone else thought.

Other than standard, turn to focus like most follow focus work now, we came up with two ways to control it and one setting. I am sure this could be elaborated on further with additional ability, but I wanted to keep this simple. Also, the fact the redmote can be run separate makes this even more exciting.

For simplicity, you have a scene with two people, different distances. You focus to the first person, you press a button (or combination), you focus to the second person, you press a button. You have now set your multiple focus points (If you need more than 2, I am sure you can elaborate further on this design).

The first issue is that you'd want to select a follow focus response curve. Like and S, or exponential, etc. This way, you can control how fast the focus goes from A->B or B->A and how the speed changes over time.

The second issue is the method in which is switch back and forth.

Method 1: You have one button. You push it once, goes to A, push it again, goes to B, a toggle if you will.

Method 2: You have two or more buttons. Button 1 goes to A, 2 to B, etc.

Method 3: You turn and encoder (like the wheel on the red mote or whichever other encoders available on your setup that you assign). The wheel does not track 1:1 with the focus, but rather, 1:1 from A->B. This way, it always takes the same distance of moving the wheel to go from A->B (which can be programmable), but better than that, once you have hit A or B, accidentally going past is ignored.

Theoretically, it makes racking focus much simpler for one person if need be. I am not sure what Red has planned for their automatic control of the Scarlet Fixed, but we wanted to at least give one of our interpretations of something (or at least a start in the thinking process) that could be VERY useful. We certainly wish we had it when shooting today!

Rick

 

[Kenneth Elkington]

I asked this question a while ago, and Jarred said that programmable rack focus will be available in some capacity. I'm hoping that some of the ways you mention will be implemented.

 

[Gavin Greenwalt]

I thought about A-B before and what I thought woudl be better than A-B is Log A-B

Have a linear focus shift from

A |----------Here to Here------------| B

But have 10% on each side for overshoot and as you are just about to hit A/B apply a bell curve to the effect so that it dampens into A B.

|--A--| _____ | -- B --|

That way you could hit fine focus a little overshoot to really dial it in while still offering a little cushion.

 

[Carey Lee Coffey]

I requested this function in 2004 over on DVXuser. No one else seemed all that interested at the time.

 

[Rick Burnett]

I saw Jarred has mentioned that in one of the epic threads I had subscribed too, but more importantly, wanted to get some dialog going about this.

One of the pain issues will be how well the electronic follow focus tracks as to how useful I think a lot of people will feel about it. For another camera, the 5D, I have seen people asking the Magic Lantern people to add firmware code to do follow focus with the wheel on the back. Having used that wheel, this seems like a bad idea to me, as it will shake the camera probably even if on a tripod and is not very ergonomically feasible IMO.

When I first saw shots of the redmote pro, I was like, finally, someone is getting it!

Gavin, this is what I meant when I suggested curves. Not even just as you mention (which is like an S-curve) but having the ability to fine tune that curve. Imagine being able to have 6-10 different types of programmable curves, or changing the rate of that curve, you could get some amazing focus changes for all sorts of different types of applications.

Of course, it's GOT to be simple and easily accessible. If there are too many steps, people will just keep doing things the old way

 

[Eren Ozkural]

Having used that wheel, this seems like a bad idea to me, as it will shake the camera probably even if on a tripod and is not very ergonomically feasible IMO.

Jusst remove the non-pro redmote then, use the click wheel away from the body

 

[Rick Burnett]

Hehe, sorry, I might have been vague. What I was referring to was the 5D (and subsequently the 7D as well), as the wheel on the back clicks as it moves, not smooth at all, and takes a bit of push. When someone mentioned focus control through that, I didn't see the advantage.

Then I saw the redmotepro, as you've mentioned, and yes, absolutely. That is the thought I had. Pull it off and have someone controlling it right next to the camera. Means less people on the dolls too

Totally awesome in my opinion!