Cinema5D has some dam good forum posts that are worth dropping in on. Take this one a USB DSLR Follow Focus post on Cinema5D from Slippers. The Follow Focus unit is battery powered and does not require connection to a PC, nor does it use the Canon SDK. Well it sounds so crazy it may just work.
Sure makes for interesting reading and viewing of the test video this development of the USB FF and word is a mid December roll out could be on the cards.

USB follow focus – focus point test with 5D Mark II from Slippers on Vimeo.

Test was filmed with a 5D Mark II and EF 50mm f/1.4 micro USM lens. AGC was disabled in the camera menu, and an external Azden shotgun microphone was plugged into the camera’s mic-in port. The microphone was approximately 3 inches above the lens.

On the controller the focus change command send rate was set to 14 commands per second, and the focus step size was set to medium. The combination of adjustable command send rate and step size allows the user to customize the smoothness and rate at which the focus will change. Lenses with true USM (not micro USM) also tend to be quieter and smoother.

Close Up of Slippers HDSLR Controller

DSLR Controller: USB Follow Focus

tested compatibility list:

1Dmk4, 5Dmk2, 7D, 60D, T2i, T1i.

All features work except on the 7D, which has a peculiarity. If you have video mode enabled, you cannot toggle live view on and off using the controller. The camera ignores the command. EOS utility and EDSDK also have the same problem. This isn’t a huge issue considering the camera automatically turns live view on when you flip the switch to video mode on the back of the body.

Canon USB follow focus test from Slippers on Vimeo.

DSLR USB Follow Focus Controller

Just a functionality update. Unfortunately, Canon’s USB implementation does not allow the camera to accept settings changes while recording, such as aperture, iso, or shutter speed. This means a “run and gun” profile is largely useless. However, it is still a good thing to be able to adjust the settings while not recording, so I have redone the profiles, and the way they work:

1. 4 focus points (2 stops, 2 points)
2. Settings – aperture, iso, shutter, exp compensation
3. Focus rectangle control (Pablo’s idea! Up, down, left, right, for use with zoom and autofocus)

You can cycle through the three profiles very quickly. Settings are adjusted by holding the appropriate button, and turning the knob. Knob sensitivity is reduced while doing this so it’s easy to select the value you want.

Also, since you can’t adjust the focus rectangle or change any settings whenever you’re recording, the 4 right buttons are automatically used for focus points as soon as recording starts. Then, when you stop recording, the profile goes back to whichever one was previously selected.

The LED indicator is used to show the profile you’re currently using.

Yellow: no camera detected (camera is either turned off or disconnected from the USB cable)
Green: focus point profile
Blue: settings profile
Purple: focus rectangle profile
Red: recording (from any profile), 4 focus points active (if you set any before you started recording)

This method makes it so you can set focus points, then switch profiles to something else, start recording, and still use the focus points. They aren’t lost simply because you changed profiles.

I am intending to ship with 8 white + 1 red installed in the controller, and then 1 each of white, black, red, green, and blue buttons in the box. This will let you have some extras and designate certain functions, if you want. Additional 10 packs of buttons will also be available for just a couple bucks if you want to change them all out.

It’s not hard to change them, either. You just have to disassemble the controller. The knob comes off with one set screw, the back plate has two phillips head screws, and there are two board mounting screws inside. Allen wrenches will be included with each controller for the knob and board screws.

Leave a Comment Here