A very promising title header – if you hate to read a “why” and “what happened” section, just skip to the middle of the article. Barbaric, though, from an ethical standpoint – like skipping over the innocent introduction in an erotic motion picture, you miss what makes the payoff actual satisfaction!

Controlling a Canon DSLR with an Android Tablet - it's possible, thanks to chainfire's Android App "DSLR Controller".
Stumble – Mumble – Fumble (with)
A few months ago, I was getting hooked on Android, and looked for cool apps for my new HTC Evo Design smartphone. By the way, if you don’t have a smartphone, get one – you will not believe how you could live without one.
Anyway, so by accident I stumbled across this App called “DSLR Controller” which promised the ability to control a Canon DSLR with an Android device. I was stoked, mumbled something like “this is it!”, bought and downloaded it – cost $8 for the DSLR Controller application by chainfire -, and tried it out. I needed to buy a USB OTG (USB On-The-Go) cable, a USB Host cable that you plug into the data/power port of your android device and it converts into a female USB plug. So, bought that on Amazon; the USB OTG cable costs $3. Quick research showed that there isn’t really an easy solution for the iPad, which made it even more exciting.
(If that makes you sad, there is a workaround for the iPad/iPhone that involves a computer)
I connected my HTC Evo phone and had to realize that it would not work – HTC Smartphone don’t support the USB Host Feature. Still, my conviction was strong, so I thought “how can I test this out with the least investment?” – the answer came after days of research about Android tablets, and I went for a dirt-cheap $100 Idolian IdolPad Plus. I unboxed it like a boss, plugged in the cable and installed the app – et voila, it works. I fumbled around with it, discovered its functions – I was blown away. So blown away that I lost the freaking Idolpad on a documentary film project in Canada, somewhere between the chainsaws and felled trees of the loggers we were documenting in “The Lives and Livelihood of Loggers“. Back via Chicago to LA, after days of research in Chicago and my girlfriend complaining about my poor attention to the outside world while researching costs, I bought the Google Nexus 7 for $250. This seemed to have been the right decision, as it was the most future-ready pad in the price range I could find. (you can also buy the $200 version, which is cheaper but has only 8GB of space).

The Interface of the "DSLR Controller" App developed by chainfire - here you see the peaking function in action.
What DSLR Controller Does
You know Canon’s EOS Utility? It’s that, but on a tablet. A genious developer and hacker reverse-engineered the USB port of the Canon DSLRs, and built an Android application that does exactly the same, with additional functionality. Basically, you can do:
- LiveView of the Camera in your Tablet/Smartphone’s resolution: On my Nexus7, that’s 1280×800, about as much as 720p – a MASSIVE difference to the SD onboard monitors out there, or the microscoping display on the back of my camera.
- Recording/Stop button and photo trigger, so you can record and stop on the tablet, and let your hands completely off the camera.
- Aperture, Shutter Speed, ISO, Color Temperature and Picture Style – just as you would do it on the camera.
- FPS and Resolution adjustments – the app recognizes each model’s capability, and will give you all options of resolution, compression (5D MkIII) and framerate.
- 2:35/16:9/Grid overlay: Super practical, it adds a bright white line, and then a dark, transparent letterboxing. Phenomenal, no more taping over the display.
- Peaking/Contrast/Exposure Display: You can show peaking in 4 different colors (red, green, yellow and white), you can show contrast (like an “Edge” Filter in Photoshop), and you can show Exposure (white/black/%grey areas)
- Live Histogram: You can display a luminance as well as an RGB histogram during recording.
- WiFi Passthrough Mode: I haven’t been able to make this work, but you can send the entire display and control wirelessly to other Android devices via WiFi.

Two 25-inch velcro straps lead through the back of the tablet's casing, allowing secure and tight points of further attachment.
Now, where is the catch? There’s a slight delay in the display (very little, but noticable), and the tablet can’t do everything, like playback or formatting cards – but apart from that, no real catch. Why do so few people know about the app? Because it’s used by a lot of geeks/developers, and doesn’t really have a track record of real life application. I did extensive betatesting with plugging and unplugging the tablet, and seeing jhow the application reacted – once I got a hang for it, I felt ready to test it in field. So, I brought it on board of two real life projects – a commercial and a music video.
The possibly Best Way to rig a tablet to a Camera, BlackMagic style.
- Cut 2 strips of velcro (one rough, one hairy side) with about 25 inches in length each.
- Insert both strips horizontally in the casing that the nexus 7 comes with – one at the top, one at the bottom. The Velcro is hereby pushed between the backside of the tablet and the inside of the casing. Through the extremely tight space in there, the strips are being held tightly, while no sewing or other modifications to the casing have to be done.
- Put the tablet flat against the back of the camera, with the display facing you.
- Criss-cross the velcro straps on the fron of the camera, leading them around the lens

The Nexus 7 with DSLR controller strapped to the back of the Canon EOS 7D, connected by a USB cable. The velcro straps cross in front of the camera, around the lens - effectively locking tablet and camera to each other, allowing the user to only hold the tablet in order to safely control the camera.
Real Life Applications – A Commercial shot on the 5D MkII with shoulder rig, and a music video shot on the 5DMkIII with Steadicam
Now it was 2AM, I was tired as hell, but knew we had at least 5000W of lighting power on set; a great chance for glare on the hard glass of the tablet. So, I found a piece of kindergarten foam sheet ($1-2) – which I bought a while back for exactly that purpose. I cut it to length, made four sections (wrapping it around the tablet to get measurements) reinforced the edges and corners with Gaff tape, and used thin, small strips of Velcro (one side glue, one side rough or soft) on the tablet’s casing and the foam sheet. Now I could wrap the sheet around the tablet case, the velcro would hold it in place, and I had a great sunshade. Not just that – if I pressed my face hard enough into the foam sheet rectangle, it would mold to my face’s shape and I had a way to eliminate any outside light – i.e. for pulling focus by visual judgement on a really bright day where every pixel recognized counts.
Now it was 2:30AM, I went to bed and got back up at 5:15AM to rush to set.
.
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The Commercial – 5D MkII & Shoulder Rig

The Nexus 7 strapped to a 5D MkII on set of a commercial in Los Angeles, California, rigged on a shoulder mount. In the picture, Tobias Deml (Cinematographer) with Ace Salvador and Izzy Traub (Directors).
This shoot was done on a 5D MkII, shot in Los Angeles and directed by Ace Salvador and Izzy Traub, some great guys who I could involve in my betatesting. I had not tested the application with the 5D but knew from the developer’s website that it should work; from my 7D I knew that it worked well in general. And it did. The tablet gave the two directors a great joy in that they could see the camera image well although we were doing such quick setups with such a small crew that made a directors monitor setup impossible. I used tape to tighten the end of my sunshade, so less glare from bright walls behind me would fall onto the tablet. I had some great rack focusing by eye judgement, since I didn’t have to guess about focus any more, like usual DSLR ultra-low-budget shoots – I could actually see where the focus was at. The histogram on camera helps a lot, but I am not 100% sure of its accuracy. A major problem was the frequent turn-on and turn-off of the camera; so after some testing on set I found this way to be the easiest, to cycle through turn-on-and-offs in order to save power on both camera and tablet:
- Exit DSLR controller with the Android exit button
- Turn off the android tablet
- Turn off the camera
- Unplug the USB cord from the tablet
- Turn on the android tablet
- Turn on the camera
- Plug the USB cord back into the Android tablet – DSLR Controller will start automatically
If any of these steps were done differently (especially the turn-on sequence, there was either no picture on the tablet, the application would freeze or it wouldn’t recognize the camera. It needed a reset (turn of and unplugging of all devices) to make it work again. As long as I followed the above sequence though, a connection was established 100% of the time. I used the peaking mode all the time, but wished I had an ability to control how sensitive the peaking function would be, or to control the size of the peaking dots – something to make them more visible. I also used the “contrast” function quite often, but wished I had similar abilities – to adjust the intensity of the line drawings. Other than that, the shoot went fucking great, and in a situation where we suspended the 5D MkII from a C-Stand on top of a C-Stand rig for a crane shot and I could not see or reach the camera properly, I just used a long USB cord to monitor the camera at the C-Stand base, set the focus as well as control the recording – a really, really helpful thing that I couldn’t have done without the DSLR controller app.
Something unexplainable happened as well, namely that in a series take I rolled the camera for 17 minutes straight, and got a recording. Somehow, the tablet must have circumvented the camera’s internal 12 minute limitation; proof below. People were murmuring on set about that being not possible, so I played back the clip at beginning and end of the clip, and it worked. Unfortunately, once we transferred all the files, the clip was only a few KB large, it must have self-destructed on the way from the camera to the transfer. I tried replicating the experiment with a 7D, but it stopped recording at the 12-minute mark. No idea how I got the 17 minute recording, but I took a photo of it.

17 Minute recording on the 5D MkII by using DSLR Controller - no explanation for how that was possible.
The Music Video – 5D MkIII & Steadicam/Tripod
The 5D MkIII has additional settings, like “All-I” for higher recording quality – which the tablet recognizes and offers as an option in its framerate settings. Strapping the tablet and sunshade to the camera and then mounting the combination to the Steadicam was fairly easy to do; it gave a decent counterbalance to the lens’ weight, which allowed me to balance the stabilizer of the Glidecam safely enough that I belly-dance with the vest and arm, without touching the camera.
The shoot was on a beach, and the sunshade with its moldable shape proved very helpful. I again ran into short trouble when I forgot my turn-on sequence, but that was fixed quickly. On this shoot, we shot much more and had to format cards throughout, which was a bit annoying, since I had to take off my velcro contraption to get access to the camera’s menu; definitely a weak point in my setup – but it’s compensated by the immense practicality of having a 7″ display right on the back of the camera, just like a Blackmagic does.
The director enjoyed the larger preview on the tablet; just playing back footage was not really feasible since the tablet cannot play back movie files. Going back and forth between tripod and Glidecam was as easy as it would be with the camera alone – the tablet and camera became a unit through the unique mounting technique.
Summary, The Bottom Line and Closing Statement
This new technique of monitoring what you film is a great new way to get better control of your pictures. With the app, you enter the world of peaking and 2.35:1 overlays on-screen; you get HD monitoring and a larger display. The delay in movement is there, but didn’t affect my two shoots in any way. The benefits outweigh the drawbacks by far, and I will keep using DSLR Controller by Chainfire as well as my Nexus 7 in future shoots. I was not able to get the WiFi passthrough ability to work on my network yet, but its capacities of sending the camera’s image wirelessly to another android device are very exciting, and the on-set possibilities are endless.
The color rendition is not 100% accurate on the tablet, so a bit of comparison to the camera’s display (both can be on at the same time) can help you judge lighting and color in the future.
The application possibilities on larger sets are very nice, as you can plug in an additional miniHDMI cable into the camera – so, a theoretical configuration for larger sets would be that the operator sees the camera’s own display, while the 1st AC monitors the camera with DSLR controller and judges focus appropriately, and the director views the camera’s image via HDMI.
Big props to chainfire, the developer who started this reverse engineering effort. Also, the Application offers attractive solutions for Photographers, like ramping and bulb exposure.
If you want to learn more about the technical side and development history of the DSLR Controller App, visit this 100-something page thread on XDA developers, moderated and responded to by chainfire himself.
The App’s website helps to get an overview of camera and android device compatibility – the application is still in “Beta” status.

Comparison in terms of color between the Canon 7D and the Nexus 7 with DSLR Controller - the camera has a slight purple tint, while the tablet has a less contrasty look, and a more yellow hue. The histograms are identical.

A Suggestion I built for enhancing the "Peaking" mode of DSLR controller - hopefully something the developer is interested in.
Related posts:
- Tutorial: Building a Shoulder Mount for DSLR Filming, $20-$30
- On-Set Audio Monitoring: How to make $30 DIY Passive Noise Canceling Headphones
- How to Build the Cheapest (15$) Camera Crane in the World – Tutorial
- FILM LTK – Filmmaking Links, Tutorials & Knowledge
- Making your Life more efficient than ever before: The Notebook / Battleplan






That’s brilliant Toby!
would be awesome to get the image recorded directly on the tablet if it was 1080p.
That ap looks great, and the idea of mounting flush with the back of the camera is pretty cool. Your 17 min. clip on the 5D was a corrupt file. The 12 min. shot limitation is not an arbitrary restriction, but a physical file size limitation caused by the formatting of the memory card. Canon uses FAT file formatting which has a 4GB file limitation (12 min. @ 1080p = a 4GB file on the 7D, and 5D).
Yeah, I figured eventually that that must have happened
Still it’s bizarre that I was able to play back both the beginning and end of the clip on the camera…!
While outputting to the monitor, does the 5d screen still work? Simultaneous output?
Yes, it does! As you can see here, the screen does stay on (that’s the 7D in this case, but should be the same for all):

That gives you the freedom of having a 1st AC use the large tablet for pulling focus with peaking functionality, while the camera operator can use the display on the back of the camera for framing – on a set big enough for a 1st AC. Or, alternatively, it can be a display that the director can look at while the operator is filming in the usual style of looking at the camera’s display.
Toby
They actually sell the nexus 7 bundled in a rig with a friction arm for mounting, you can see it here: https://dslrpros.com/Products/tabid/94/CategoryID/0/List/0/Level/a/ProductID/28/language/en-US/Default.aspx
I stumbled across it a couple of weeks ago and immediately got hooked on the idea, the fact that you’ve tested it is reassuring, I can see this developing further in the future. Thanks for posting!
Whoa, that’s pretty cool! I was actually looking for an articulating arm rig for this solution when I started my search, but eventually felt that any situation where I’ll have a shoulder mount and running/jumping involved will add so much inertia away from the camera’s center of gravity that I’d get way more wobble than if I had no tablet on there.
Still, that rig that you posted could theoretically just have the tablet swing back onto the camera and lock it towards the back, which would deal with the inertia problem.
I looked – but couldn’t find any real solution, maybe someone wants to prototype this – for a way to use the flash shoe of the camera to position a hinge on top, and attach small brackets on the bottom of the camera:
The tablet would mount to the top hinge, which could swing up and down, and the brackets on the bottom would allow the tablet to click in and lock it in position – basically, the same idea as the Velcro straps in terms of mounting position and zero freedom of movement for the tablet, just in a more mechanical form than the straps, which would speed up the moments of taking the tablet on and off.
Will it work with magic lantern installed on the camera?
I guess whether the app included support for that.
yes, it does – I haven’t tested it myself with ML yet (waiting for the Beta status on the 7D), but I read of multiple people on the XDA developer thread that ran it with ML. This thread on the ML forum confirms it:
Hi , what version of the DSLR beta allows focus peaking ? Is Sept 12 the most recent ?
I am using the one you can download as of today directly from Google Play