DIY Follow Focus for DSLRs

With HD video being all the rage, I thought I'd share how I made a simple follow focus for my DSLR. There are several different ways to do this, I know I've seen a couple of other DIYs for the same thing on youtube (e.g. using rubber bands, jar openers), but I made mine with the materials I had lying around or nearby, in true MacGyver style :)

Enjoy!

Step 1: Materials

First of all, what is a follow focus?: A follow focus is a focus control mechanism used by videographers to be more precise in focusing on a subject while its moving, or to smoothly change focus from one object to another while filming. No one wants to see the camera shake when using the manual focus ring on your lens. A follow focus is a way to operate your focus more efficiently.

For materials, you will need:

1. a dslr camera
2. a cheap magnifying glass ($1)
3. A knife or sharp object with which to cut
4. One "m-wave" reflective leg band, that can be tightened and loosened (a set of two costs $5)

Comments

[ryanjblajda]

i like the DIY but why no clothes? lol

[pudi.dk]

Heating a knife will undo the tempering, making the blade softer. Don't do that to a knife you like.

[pufferfish9108]

not nessecarily. if you only heat it for a short time (the time needded to make it go through plastic) it may even temper it more

[Jakob2803]

Put some clothes on!

[ZaneEricB]

Do i start this project with or without a shirt on, or is that a step you forgot to list?

I dig the simplicity thought...you got my vote!

[DoxxRoxx]

I was originally going to add this defensive comment:

"I'm guessing the 'topless' comments would have been much different if the author had been female."

Until I went to the <TWOWEEKSOFF> website and saw the 'sweet' still photography there, read the bio, and then became enlightened.
Yeah.
Why as a society are we so hung up on clothing, or the lack thereof?
And hair length. What's that all about?

To tenzijth,
Nice job on this! Years ago, I used a similar technique on a video camera that had a one-speed zoom that was way too fast. I really appreciate the 'instructables' spirit and simplicity of this project. This is a project accessible to someone like me who doesn't happen to have a laser cutter, 3d printer and/or CNC machinery just laying around the house. Or the newest DSLR equipment, for that matter.

Good luck in all your endeavors, and keep capturing the moment.

[John T. McF. Mood]

You've completely omitted the fact that many DSLRs that can do HD video, can do on-the-fly weighted auto-focus. For the type cameras being used by the inventor here, it's a good, and rather ingenious solution. I'm not being critical of it, but my camera obviates the need for such a device My camera was primarily designed for stills, professionally, and hasn't all the handles and such you describe either. And an experienced stills photographer can shift gears, brace his or her body, use a mono-pod or tripod and shift gears to film easily.. The 'lines' between still and motion picture are becoming smaller and soon will be non-existent. I've been photographing (still and film/video) for over 50 years, and I admire the inventiveness here. But sometimes there's no need to re-invent the wheel. AUTO-FOCUS....works quite well. And on the fly too.

[John T. McF. Mood]

Why bother when you can set the AUTO FOCUS and the ANTI VIBRATION controls so that you do a smoother and less geeky looking video anyhow.

[rusty0101]

Whether it's good or bad, some dslr's disable the auto-focus when you are in video capture mode. There may be many reasons, such as the videoagrapher wants the subject to be in one of the 1/3 corners, and the auto-focus will insist on trying to focus on the background, which may very well not have any contrast for the AF to work with. You'd end up with a video where the focus goes in and out through the entire focus range of the lens, and you end up with video that's not of any use. You may also be working to capture video of a person in a crowd, and then need to switch to someone else in the crowd without actually moving the camera.

[graydog111]

rusty0101, I may be mistaken, but I thought you could focus on the subject, hold the shutter button halfway down to hold that focal length, move the subject to "one of the 1/3 corners", and then push shutter button down.

[rusty0101]

For a Photo yes. Not for video. The Instructible is related to taking video where you would not be moving the camera around for focus. In this case you want to be able to adjust the focus on the fly, with as little movement of the camera in the process.

Most of the higher end prosumer rigs mount the camera on a shoulder rig that the videographer uses both hands to control for stability, and the follow-focus control is either a rotating handgrip (think motorcycle accelerator or bicycle gear shifter) or a thumbwheel on the rig. Either is going to control the focus for the lens through a cable system (like a bicycle's breaks.) Again this isn't all that helpful with single shot photography, but is not at all uncommon when it comes to video work. And DSLR's are very common these days in capturing videos.

[antonomasia]

This has nothing to do with using auto focus - AF would be turned *off*. Please learn about video- or cinematography first and have a look at items like this US$15 device: http://www.b-hague.co.uk/hague_follow_focus_zoom_lever.htm or this one for $50: http://reviews.photographyreview.com/focus-shifter-affordable-follow-focus-digital-slr-video . The OP's solution isn't elegant, but it *would* work for the intended purpose.

[AnnetteS]

Awww! I think he's kind of cute w/o a shirt. But there aren't many other guys who can pull it off (so to speak), so I hope they don't try.

[John T. McF. Mood]

My DSLR has a continuous duty auto focus ON while using to film, you can choose weighting before shooting, and then go. It's Nikon, and I highly recommend them. The newer D3200 has 24 MP and I'm shooting for that one next as I will share lenses I have already with my D5100. A great reason to research what you are about to buy first so you don't get stuck with clumsy work arounds. (Not that this work around isn't ingenious, it's just not necessary for some DSLRs.)

[DavidM45]

Brilliant, I've got the 18-135mm looks like the grip area is about 73-75mm so a 2.5" or 2.75" would work. What size did you find? Dollar store or where? I'm surprised there isn't enough tension in the magnifier ring to use it as is, without the leg things.
thanks for the idea

[mretuck]

Weird how many people are snarky toward your build. I appreciate both your efforts and your diplomacy toward snarky folk.

[tenzijth]

Thanks, mretuck!

[danzo321]

Clever and cheap, but PRACTICE is your best strategy in follow-focusing.

[perrociego]

and your camera lens will scratched with the edge of the reflective leg band...

[graydog111]

Am I missing something? Why are the ends of your "reflective leg band" sticking out instead of "tightened it to hold the magnifying glass plastic securely".  Looks like those ends would catch on everything. 

[graydog111]

Am I missing something? You said, "and tightened it to hold the magnifying glass plastic securely". It looks loose to me with the ends sticking out and subject to catching on everything.

[AtlantaTerry]

You keep calling it a "magnifying glass" when it really is just the frame as you removed the plastic element.

Geez, I watch too much "Big Bang Theory"...

[aram.bv]

was that a sarcasm? :D

[tenzijth]

This is true (regarding magnifying glass, I can't comment on how much BBT you watch... :)

[totszwai]

dude... a real follow focus work like this:
http://en.wikipedia.org/wiki/Follow_focus

your "follow focus" does nothing, since you are just turning the focus adjuster EXACTLY like stock.

[tjesse]

Dude... With some practice this can be a suitable substitute. According to your own source, a follow focus "does not contribute to the basic functionality of a camera but instead allows the operator to be more efficient and precise". Extending the radius of the stock focus extends the length of travel, making it easier to do fine adjustments.

[tenzijth]

Hey totswai,
Yes, I admit, this won't compete with those in the least, but it has helped me in the sense that I don't bump the camera body with my hand when trying to just use the focus ring.

[elabz]

Add to the list of materials: T-shirt ($5)

[dnicke]

Nice one! I might try this one out sometime. Although the weight of the handle would cause your focus to drift if you ever took your hand off it.

[tenzijth]

Thanks, dnicke! The trick is to get a really cheap magnifying glass. The plastic is super light so it doesn't change the focus on its own.

[migaspepino]

How did u assemble it?

[amendez6]

why the no shirt picture?

lol

[crazyg]

otherwise known as a bicycle clip. nice documentation style.and the hot knife reminds me of a completely different activity !

[bobcat1947]

Like the idea of anything useful and home-made. I'm an old guy. Pardon any Q's that may sound stupid. My camera looks similar to yours; it is also a Cannon DSLR. It has a zoom feature (that I presume is operated by a tiny internal electric motor). Will a device like yours in any way harm that mechanism? (it would seem you'd be "forcing" the gearing that usually operates the zoom.

[tenzijth]

Hi bobcat,
Thanks for your comment. I only use this when focus is set to Manual. Using my follow focus device on Auto would, indeed, harm your camera, as would trying to force it with your hand.

[toborock]

why the f*ck are you naked dude?

[wiebevandomburg.hotmail.com]

Haha exactly my question :d

[tenzijth]

Um, I wasn't. Dude.

[c3ralki1l3r]

is it really hot where you live in winter time then?

[toborock]

Dude im sorry, nice instructable. I was just wondering why no shirt.