Scott G Sanders

DIY Infrared (IR) Transmitter for the iPhone App DIY IR Transmitter | Finished ProductAbout a week ago I saw a post on the DIY Photography blog about an iPhone app that can trigger your DSLR called DSLR.Bot ($4.99).  After watching another DIY video on how to make the IR transmitter I felt like this was a great little project to tackle.  The app and the IR transmitter act like a wireless intervalometer.

I already have the Nikon ML-L3 Wireless Remote, but I enjoy creating HDR images and my Nikon D40 does not have a built in bracking function so all my shots are done manually which takes extra time and the clouds will not wait.  After doing some research on the website I found out that this has not been tested with the Nikon D40.  I contacted the developer and asked if there was a lite version to trial before dropping the $5.  Unfortunately there was not, but I was given a promo code to use to download the app for free.  (Please do not bother the developer with a similar requests if your camera model is shown as tested on the spec page.)  DISCLAIMER: I have not been asked or pressured by the developer to provide a review, I am doing this on my own.

My main goal was to develop an IR Transmitter that looked professional. My second goal was for the transmitter to fit on my iPhone 4 without removing the bumber or using a cable.

The first step was to track down all the pats.  I tried to use 2 IR LEDs from an old TV remote, but they required too much power and the output adequate to trigger the shutter in daylight.  After, picking up the High Output Infrared LEDs (Model: 276-143) at RadioShack for $1.99/ea I got to work.  I already had a headphone plug so I just needed to find something like a project box to house it all.  I could not really find anything I liked then I found an old drug rep paperweight made out of acrylic.  Now, I had everything I needed. DIY IR Transmitter | Acrylic Paperweight

Starting with the Acrylic paperweight I cut it in half then into a cube. DIY IR Transmitter | Acrylic Paperweight Cut Down DIY IR Transmitter | Acrylic Paperweight Squared

Next, I drilled a hole about 3/4th of the way into the block. Then i tapped the hole to allow the headphone plug to screw into the acrylic.
However, before screwing the headphone plug into the block I cut about 1/4″ off the cube. This will provide me with a cover for my DIY project box. DIY IR Transmitter | Drilled - Tapped - Sliced DIY IR Transmitter | Headphone Plug installed

Now it was time to drill 2 holes for the IR LEDs in the larger acrylic cube. DIY IR Transmitter | IR holes drilled

On the back side of the block I now had 3 holes. 2 for the IR LEDs and 1 from the original hole for the headphone plug. I used a Dremel to bore out a cavity for the electronics to live. DIY IR Transmitter | IR holes cavity

This next part was the trickiest part of the entire build. I had to dry fit the IR LEDs and determine the placement of the wiring before I could solder them together. DIY IR Transmitter | IR LED Dry Fit

After careflully bending the post I soldered the 2 IR LEDs together.
NOTE: It is important that you make sure you reverse the polarity so it they are connected from the cathode (-) to anode (+) to cathode (-) to anode (+) DIY IR Transmitter | IR LED Soldered

This is a look at all the parts used in this build. DIY IR Transmitter | Wiring

Just a little bit of wire is required to connect the IR LEDs to the headphone plug. I could have attached the IR LED post directly to the plug, but I wanted to use a bit of wire to give some wiggle room. DIY IR Transmitter | IR LED Soldered Complete

Now that the wiring was complete I felt it was time to test it out before going any further. DIY IR Transmitter | Test Fire

Now it was time for final assembly. I have this amazing glue made for welding plexiglass called Pro Weld from a company called Ambroid. This stuff is great for fusing acrylic and other plastics. I’ve used this stuff since I was a kid making plexiglass enclosures for models.

Using the Pro Weld I fused the 2 halves of acrylic. This stuff works in a about 30 seconds.

After the halves were set I started to shape the cube. Again it was time for the Dremel. I spend about an hour shaping the cube into the final shape.  An hour really, Yes, I did not want to mess it up and cut into the cavity. DIY IR Transmitter | Final Shape IR End

I even ground down part of the headphone plug and tapered the underside to allow the transmitter to fit into the iPhone without removing the Apple Bumper Case. DIY IR Transmitter | Final Shape Plug end
I did some additional polishing with the Dremel to give it a smooth and somewhat shinny appearance. I could go an extra step flame polish the acrylic for a glass like finish, but I am sure it will get scuffed up in my camera bag when not in use so that is not really important. Besides, I do not want to accidentally hit the IR LEDs with the torch as it would ruin all the work up to this point.

Now for the final test shot. DIY IR Transmitter | Finished Product

I did run the DSLR.Bot ($4.99) through the various functions: Single Shot, Long Exposure, Time Lapse and my favorite Bracketing. All functions passed with flying colors with my Nikon D40.

I used the Bracketing function to shoot a 5 shot HDR of an old vacation trinket.  It is not much, but I wanted to bracket something for this post.
Ye Olde Prospector

I  cannot wait to use this app for my HDR work.

UPDATE: Here is my first HDR using the app and the IR transmitter.
Cinderella's Castle






31 responses to “DIY Infrared (IR) Transmitter for the iPhone App”

  1. franco Avatar

    awesome! whats the voltage of those leds? ; )

    grretings from argentina!

    1. Scott Avatar

      Per radioshack’s website: Forward voltage (V): 1.28V, rated at 100mA

  2. een Avatar

    Did you use the app for long? i am not too happy with it as i tried to shoot overnight in time lapse. it didn’t last that long and i can’t get the screen off to save power.

    1. Scott Avatar

      I’ve only used the app for bracketing HDR as my D40 does not have built in bracketing. I am not happy with the times avaliable, but this is a limitation of the IR not the app. This is the last HDR shot I took with the app.

      Cinderella's Castle

  3. Jay Avatar

    I was wondering where you got that 3.5mm headphone jack with the wire pins. I was trying to do a similar build with existing headphones but it hasn’t worked yet. Think you could tell me so I could make something like this?

    1. Scott Avatar

      Radio shack. The black plastic unscrews from the plug.

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  6. Jason Avatar

    I came across your site looking for something else and realized that the voltage coming out of a headphone jack is AC at maybe .5V those IR LED’s are DC at 1.2V and barely work (2″ or less) at less than .75v DC. You would need a rectifier of some kind to change that voltage unless the IPhone has a DC output on its headphone jack.

    1. Scott Avatar

      Thanks for the technical information. I’ve not tested the distances at which this specific setup works, but it does indeed work.

    2. AllenH Avatar

      I was trying to figure this out myself- I’m also used to a few resistors to drop mostly voltage across the Led, not current- the only thing I can think of is that the led’s themselves are doing some rectifying? They’re set at opposite polarities- could each one take half the waveform?

  7. John Padgett Avatar
    John Padgett

    Will the Apple headphones that come with the the iPhone work?

    1. Scott Avatar

      John, I’m not really sure what you are asking.

      After seeing your other post on DIY Photography I realized what you were asking.

      You can use the Apple headphones, just make sure you use the correct wires as there is extra for the microphone. I cannot offer any additional information on the Apple headphones as I’ve never dissected them myself.

      I did find a set of pictures showing a teardown of the headphones by jeffb on Flickr.

  8. Enzo Avatar

    I didn’t understand why you have used two leds… Is it only to increase the power of the ir?
    Can I use only 1 or it ll not work?

    1. Enzo Avatar

      Really I want to built a controller for tv not for the camera but I think it is the same

      1. Scott Avatar

        You are probably correct. You would need to develop a sound file for each TV command. In theory you should be able to use this IR Transmitter to control any IR remote controlled device as long as you can develop the sound files to trigger tue LEDs.

    2. Scott Avatar

      I used 2 IR LEDs because that’s what the original wiring diagram showed.

  9. Utkarsh Avatar

    Can I use only one led?

    1. Scott Avatar

      I am not sure if it would operate with a single IR LED. The original design I followed had 2 so I’ve not tested the alternative single IR LED setup. I would suggest testing it out before finalizing the design. Let me know how it goes.

  10. Arvus Avatar

    You can’t just use a single LED. This is because of the way stereo sound works. 🙂

  11. USER120487 Avatar

    Is it okay to use a non high output ir led? if so, is there a way to hook it up to an external power source?

    1. Scott Sanders Avatar

      I am not sure as I just built the one based on spec. The parts are cheap enough to experiment.

  12. jan ger Avatar
    jan ger

    Thanks for the tutorial… everything worked allright. I even tested my Leds with my webcam but it wont work with my Canon 60D ?! Any Suggestions?

    1. Scott Sanders Avatar

      Did you check the settings within the app to make sure it was set to Canon?

  13. mark Avatar

    i dissected a nokia earphone and an earphone splitter (so that two persons can share the audio on iPhone for example) but the two won’t work. Anyone has an idea?

  14. gerry Avatar

    hello scott, i have just built one according to your directions, it does work on my canon and nikon but only if im real close 0-4 ft. i used led’s from an old cable box remote, is that why the distance problem, are the radio shack led’s stronger. our radio shack stores in my city in canada do not sell leds. i noticed in the previous posts that you said you had not tested yours at different distances, have you done so since then and how was the outcome.
    thanks gerry

    1. Scott Sanders Avatar

      I have not used mine in quite a while, but it did work beyond 4ft. I cannot say for sure, but the LEDs I used could very well be the difference. I did try to use LEDs from an old remote, but they did not work very well. Did you try to order the IR LEDs from

      1. gerry Avatar

        thank you for the reply scott, im from canada and our radio shack stores now called the source do not sell them. when i went to our electronic store all they had were colored ones and the kid could not tell me if that would make a difference or not. i would like to get them locally so as long as i ask for high intensity 940nm IR led i should be ok right ???

  15. snoop911 Avatar

    I’d like to use my android to control my tv directly via IR. Would this hardware work for that? (Assuming I create my own 38k carrier frequency wave file in Audacity that has the right pattern).

    If so, does this work in the same fashion as all those commercially available ir emitters? I’ve never opened one up, but they usually have a 3.5mm plug on one end that goes to a pc, with the other end having one or two ir blasters. The blasters are usually very small, so I wouldn’t think there’s 2 leds back-to-back.

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