# Turn a TI Graphing Calculator into an Intervalometer and Create Time Lapse Videos

I've always wanted to make time lapse videos, but I don't have a camera with an intervalometer feature built in. In fact, I don't think very many cameras come with such a feature (especially not SLR cameras).

So what do you want to do if you want to make time-lapse videos? You can buy a commercial intervalometer (yeah, right). You can check out some instructables like this one and make one yourself out of electronic components.

But what if you don't have the time/skills necessary to build one? You just want something quick and cheap.

Well, you can actually use a common TI graphing calculator (I don't know of any high school student without one of these) and hook it up to any camera with a remote shutter release socket. It's quite easy, and depending on your camera can require no electronic work at all.

## Step 1: Parts Needed

Here's a list of parts you need:

A TI graphing calculator - I'm using the TI-83+. I haven't tested my code on any other model, so I can't guarantee it will work.

Camera with remote shutter release socket - I'm using the Canon EOS Rebel. This has a 2.5mm socket that you can use to connect to the calculator. If your camera does not have a 2.5mm shutter release socket, you will need to create some sort of link cable that can connect the two together.

## Step 2: Program The Calculator

Depending on your calculator, this process might be a little different. The following directions are for the Ti-83+. I will try to get instructions for different models, but I will also have to convert the program to work with them also.

1) Turn on your graphing calculator (duh)
2) Press the PRGM key
3) Press the Right arrow twice to highlight the tab at the top titled "New"
4) Press ENTER
5) Enter in a name (I used "Camera")
6) You are now ready to insert the following program. The functions prompt, while, for, and end can be found by pressing the PRGM key again. The function Send has to be selected by press 2nd -> 0 (catalog).

Here is the program:

: Prompt A
: While 1
: For (H,1,A,1)
: End
: Send(A)
: End

This is a very simple program. I wrote one once that kept track of how many images were taken, displayed the estimated time remaining, etc, but it seems that it drains too much battery life and for some reason the calculator actually slowed down after a certain number of images. It might work better if you write the program on a PC in assembler, then send it to the calculator, but you need a special link cable, and that kind of defeats the point of this instructable.

Update:

The above code is claimed to work on both TI-83 and Ti-84 models.

Thanks LightShadow756 for sending me the following code for the Ti-89:
(Program)

camera(pics,delay)
Prgm
0->x
While x < pics
For y,0,delay,1
EndFor
Try
x+1->x
SendChat a
Else
ClrErr
EndTry
EndWhile
EndPrgm

(End Program)

## Step 3: Making the Connection!

This step should be pretty easy depending on what kind of camera you have. Most TI calculators have a 2.5mm audio jack used for linking two calculators together. It turns out my EOS rebel uses the same type of jack, and there is no conversion required.

However, if your camera uses a different size audio cable, you might need to use a adapter. Even worse, if it uses a different shape connector, you might have to buy or make an adapter (I know cameras like the canon 10D have shutter release plugs that are specially made for them, it's very hard to find these types of connectors).

## Step 4: Set up your shot.

This is where the fun starts. Don't plug in your calculator yet.

First, decide what you want to photograph. If outdoors, try to do this at a time where lighting conditions remain fairly constant. Also, try to shoot away from the sun.

Set up your shot - Use a sturdy tripod and don't zoom in too tight. Don't forget that things can change over a long period of time.

Focus - After focusing, switch your camera to manual focus, or use a lock focus feature if your camera has one. This step is very important because your camera might decide to focus on something else in the picture if your subject moves. It won't look very good if the focus is rapidly changing in a video. Also, if you're photographing the sky and there are no clouds in the frame, the camera won't be able to focus on anything at it might not take a picture at all.

Set the exposure - This step might be even more crucial than the focus step. If your camera has a manual exposure mode, or a lock exposure mode, it is very important that you use it. Like with the focus, exposure can change over time and it doesn't look good at all when your video is getting brighter and darker very quickly.

Set Quality - Depending on your camera and how much resolution you want, you will need to adjust your picture quality. My canon rebel can take pictures up to 6.3 megapixels, but this is very unnecessary if I'm going to make a small video to put on youtube.
Also, depending on your computer, it will take a LONG time to open up 200+ photos taken in the highest quality.
So, I usually turn my quality down to the lowest setting.

Some optional steps
Turning picture review off - If you want to save battery life by not having the LCD turn on every time you take a picture, remember to turn the image review off.

Turn camera sleep off - If you're going to be taking pictures with very large delays in between, you'll need to turn your camera sleep mode off. (This will drain battery faster though. If you're really worried about this you can actually modify the program to "wake up" the calculator before attempting to take a shot, this way you can keep the calculator in sleep mode. However, I think this is unnecessary).

## Step 5: Shoot the Photos!

This part is fairly easy:

Connect your Camera and Calculator - Use the link cable from part 3 to connect the two

Start the program - Turn on your calculator and press the PRGM button. Find the program you made on the list, and press enter.
On your screen, you should see the prompt "A=?". Enter in the amount of time you want in between the pictures. Note: this is not the amount of time in seconds. I think about 100 of these make a second, but this can change depending on battery life and your calculator model. If you don't want to think about this conversion every time, you can add a small piece of code in the program to do it for you.

Press Enter - Your camera should start snapping away! Now sit back and relax and make sure nothing explodes.

Turn the Program off - When you're done shooting, you can turn the program off by pressing or holding the ON button. You will see a prompt that says "ERR: BREAK". Just highlight Quit and press enter. The program will now be stopped and you can turn your calculator off.
If you want to restart the program, all you have to do is press ENTER again, you don't need to go to the program dialog again.

## Step 6: Compile the Video!

Now that you have all your pictures, all you need to do is put them together into a video. There are many ways you can do this.

Youtube has a guide to compiling a video using Windows Movie Maker here. What I don't like about this though is that you can't easily change the framerate of your video, so the final product will look slow and choppy.

Personally, I like to use QuickTime Pro from Apple (as much as I don't like Apple...)
First, copy all of you photos onto your computer hard drive and put them into a folder.

You will probably want to resize all of your photos beforehand. This will prevent your computer from freezing up if it tries to open up too many large photos with quicktime. I suggest using Windows XP PowerToys image resizer which you can download directly here. It's very easy to use and you can resize all your photos in a snap.

Next (if you're using Quicktime Pro), go to file > Open Image Sequence. Select the first image from your video, and press Okay. Your video should be automatically created!
Then, select File > Export. This is where you might have to play with the settings. If you want to upload your video to YouTube, I suggest looking at this page.
If you want your video to be streamlined for Youtube, select "Movie to MPEG-4" in the export dialog, then click the Options button to change more options around. I've included a picture with some settings, but I'm not very good with video stuff, so please experiment to find what suits your needs.

If you want a higher quality video, I'd suggest AVI or a Quicktime Movie format, but once again I'm not very good with this so please experiment.

If you don't want to "buy" Quicktime Pro though, there are many other options. It's really beyond the scope of this instructable though, so I'll leave that up to you. A quick google search for "Stop Motion software" should yield plenty of results.

I won't go much more into this as it will vary greatly depending on your setup.

## Step 7: Enjoy!

Here are a couple finished videos I've made using this method.

It would also be nice if anyone who knows how to program later model calculators (Ti-84, 86, and 89) could write some programs to do the same thing. I could probably write the programs but i wouldn't have any way of testing it.

Have Fun!
 1-40 of 266 Next »
kplathe says: 1 month ago
Does not work for Nikon D3100. I have all the pieces but in order for it to work I need to splice two cords together. The calculator cord and the shutter remote cord. So close though. The audio jack port on this camera is for a/v output.
softenersreviews says: 9 months ago
Loved it. The theme, the climactic and triumphant ending. Absolutely brilliant. I smell an Oscar!
Otterblue says: 1 year ago
Wow! This is great! Thank you so much!
kbaker18 says: 1 year ago
Can this be done using the Nikon D3100? Can the calculator be hooked to the Nikon D3100 and used as a intervalometer for a time lapse film?
abhinav777 in reply to kbaker181 year ago
As long as your camera has a 2.5mm or 3.5mm remote shutter trigger, this will work. I do believe the 3100 has the port, but I am not certain.
botunkus in reply to abhinav7771 year ago
Can't get this to work with a Canon 30D or 40D even though I have adapted the 2.5 mm plug to fit the canon trigger that goes into the camera. Will this only work with a Canon Rebel?
abhinav777 in reply to botunkus1 year ago
The N3 connector type is identical to the TRS connector in terms of wiring. Only the shape is different. It should work just the same. I'm not sure why it's not working on your 30 or 40.
Philosocrates says: 1 year ago
Does anyone reading this know how to program a Casio fx-9750Gii to do this? I have tried every variation in the posts but I get a syntax error every time.
My TI-84+ didn't come with one of these wires. Does anyone know of a website or store i can buy the right wire from if I want to do this? thanks :) I'm so excited to try this out
Snoopy101x says: 1 year ago
I know this is sort of an older instructable. I have a Nikon D3000 and a TI-89 Titanium, and I have yet to get this to work. If anyone has any advice I'm all ears.
TechDan says: 1 year ago
I used this method just a back in 2009 to make a time-lapse plane construction video over a weekend. http://www.youtube.com/watch?v=QjARFrVcRKM&feature=plcp&context=C39b2812UDOEgsToPDskLvuiKUi0c_6WJh8JoTfJs0

I'm about to use it again for a new plane. Helps a lot with illustrating construction techniques for new students.
brodgers1 says: 2 years ago
Okay, looking at the code, I'm a little confused by this line:
For(H,1,A,1)
What is H? And if someone has previously set H to represent a number, would it mess up the program?
mpilchfamily in reply to brodgers11 year ago
The For() statement sets up a loop. The "H" in this case is the variable the For() statement uses to store the number of passes the loop has made. The next variable designates the number to start with. The "A" is the number of loop that have to be made before the program moves on again. The last variable is how much the counter progresses after each loop. So H is set and zeroed out each time the For() statement starts. Check your manual for more details about the For() statement.
silentfallen says: 3 years ago
After playing some with the program setup you gave .. i liked it but i didn't like the fact that i had no choices.. So i made my own.
If you are interested give it a try..
( the % are supposed to be arrows.. the STO key above on/off)

.................................................................................
Disp "START DELAY IN"
Disp" SECONDS"
Prompt A
A*333.3333 % W
Disp "HOW OFTEN IN"
Disp "SECONDS"
Prompt B
B*333.3333 % X
Disp "HOW MANY SHOTS"
Prompt Y
For(H,1,W,1)
End
Send(A)
Y-1 % Y
While Y>0
Y-1%Y
For(H,1,X,1)
End
Send(A)
End

...............................................................................
As you can see from what "solupine" showed.. you need to multiply your delay (seconds) by approx. 333.3333 to get the camera to fire at the right time...

The first delay , is how long till it takes the first shot.
The second delay, is how often between shots

This was done on a TI-83+ , if you try it on other models post it up if it works or not please..
karanbhvsr in reply to silentfallen1 year ago
You sir, are a genius! OP's program didn't work but yours worked flawlessly (so far). Thanks to instructables, I've built an intervalometer and a shutter release for less than \$20! (Calculator doesn't count :P)
walamoonbeam in reply to silentfallen2 years ago
I'm assuming the answer is no, but sometimes there are spaces between the % in your instructions and other times there are not, so were those spaces a typo? Or do you actually need to include them.
silentfallen in reply to walamoonbeam2 years ago
its been a while since i have played with this but i think you dont have ot have the spaces in there.
Frnc11 in reply to silentfallen3 years ago
Do you replace the items in quotes with the value you want or should I enter it as shown? As in Disp "HOW MANY SHOTS" or Disp 24?
silentfallen in reply to Frnc113 years ago
Enter the program how it is writen above with the % replaced with the STO key (above on/off) and run it .. the Disp lines are just text outputs so you know what to input .. for the how many shots one for example the Disp"HOW MANY SHOTS" is the text question for the line below .. Prompt Y ..

to understand it the best i suggest putting it in as i have it above and running it .. it will explain itself..
Frnc11 in reply to silentfallen3 years ago
The program seems to run fine. No hickups or syntax errors, however, my camera refuses to fire the shutter. I have checked and re-checked the code for any flaws, but have yet to find anything. Any suggestions on what might be causing this problem?
silentfallen in reply to Frnc113 years ago
what type of camera are you trying to fire??
Frnc11 in reply to silentfallen3 years ago
I've tried an XTi, Rebel 2000, and Rebel G. Same results.
Frnc11 in reply to Frnc113 years ago
The program WILL fire the shutter. As it turns out, the shutter button needs to be pressed halfway down to allow the camera to meter. Is there a fix for this? As in, a way to program the calculator to automatically meter prior to taking the shot?
silentfallen in reply to Frnc113 years ago
ah yes i should have added that i guess. you need to be in Manual Focus to make this work without pressing the shutter down half way. I am not sure if you get program the calculator to do both.

I my self do not have the spare time anymore to reprogram it to see if i can get it to work. if anyone out there has any ideas on how to program it please feel free to post it.
silva_pedro says: 1 year ago
Somebody has some idea or recomms for the same project but using HP48GX+ and Nikon D100 ?
The Insomniac says: 1 year ago
Any chance this would work with a Nikon D40? It doesn't have a 2.5mm socket, but it does have a USB mini port that can be utilized, assuming I had the right cable. Thanks!
scoutx says: 2 years ago
Great work

Used my Ti-83 and Canon 1000d ( Rebel XS)
tylercard says: 2 years ago
Great work
Wally_Z says: 2 years ago
I have written a few programs for my TI-84+ Silver Edition. Most of the programming is the same for the TI-82, TI-83, TI-84. I haven't done anything other than write simple conversion programs. If anyone can find me a link or something to more advanced programming for the TI-80 series I will be eternally grateful. If you want a few programs I made, message me.
cgoldsmith3 in reply to Wally_Z2 years ago
Can i have the codes for the ti-84 silver edition????
zx3fred in reply to cgoldsmith32 years ago

Bumping from below------------------

From Luberack (Mar. 10, 2011)

I also used silentfallen's program below. Very nice! I did notice that the timing seemed to be a bit off, so I ran the program at various times in front of a stopwatch. I put the numbers in Excel and got the slope of the linear trendline that tightened up the timing tremendously. Here's the scale factors you should use for the TI-84 Plus (not sure about others):
[note: "%" should be replaced by pressing the "STO>" button.]
A*750.64 % W
B*750.64-704.12 % X
So here's what the whole program will look like:
.................................................................................
Disp "START DELAY IN"
Disp" SECONDS"
Prompt A
A*750.64 % W
Disp "HOW OFTEN IN"
Disp "SECONDS"
Prompt B
B*750.64-704.12 % X
Disp "HOW MANY SHOTS"
Prompt Y
For(H,1,W,1)
End
Send(A)
Y-1 % Y
While Y>0
Y-1%Y
For(H,1,X,1)
End
Send(A)
End
...............................................................................
hit "QUIT" to save and exit programming

Wally_Z in reply to cgoldsmith32 years ago
So you would like the coding for some programs I wrote?
In the TI-83+ I
1) Turn on your graphing calculator (duh)
2) Press the PRGM key
3) Press the Right arrow twice to highlight the tab at the top titled "New"
4) Press ENTER
5) Enter in a name (I used "Camera")
In the step 6) I Pressed program, but does not appear Prompt . Can anybody Help me.
Thanks,
R.Gil
Prompt is found by pressing PRGM -> tab over to " I/O " then scroll down to "2:Prompt" -> "Enter"
How do you put Send (A)?
H and A mean?
Thanks,
R. Gil
PRGM -> (tab over to "I/O") -> scroll down to "B:Send( " -> " A " -> " ) "
luberack says: 2 years ago
TI-84 Plus Silver Edition, and Canon EOS Rebel T1i:

I had modify the cable to make it a "cross over" cable. Assuming Tip is #1, Middle is #2 and Base is #3:

1 2 3
X |
1 2 3

So, Tip "crosses over " and connects to the Middle on either side. Base remains a direct connection.

Camera also has to be in Manual Focus mode (usually a switch on the lens).

Otherwise, when triggered the camera will only "half press" the shutter. So you'll hear it autofocusing, but not releasing the shutter. Using the Cross Over Cable and the Manual Focus fixed the problem.

I also used silentfallen's program below. Very nice! I did notice that the timing seemed to be a bit off, so I ran the program at various times in front of a stopwatch. I put the numbers in Excel and got the slope of the linear trendline that tightened up the timing tremendously. Here's the scale factors you should use for the TI-84 Plus (not sure about others):
[note: "%" should be replaced by pressing the "STO>" button.]

A*750.64 % W

B*750.64-704.12 % X

So here's what the whole program will look like:
.................................................................................
Disp "START DELAY IN"
Disp" SECONDS"
Prompt A
A*750.64 % W
Disp "HOW OFTEN IN"
Disp "SECONDS"
Prompt B
B*750.64-704.12 % X
Disp "HOW MANY SHOTS"
Prompt Y
For(H,1,W,1)
End
Send(A)
Y-1 % Y
While Y>0
Y-1%Y
For(H,1,X,1)
End
Send(A)
End
...............................................................................
hit "QUIT" to save and exit programming.
zx3fred in reply to luberack2 years ago
Works perfect! Thanks for the post. I use a 2.5mm (male to male) stereo cable for mine. Radio Shack has them, if not use a 3.5mm stereo cable and two adapters to get the 2.5mm ends.
luberack in reply to luberack2 years ago
ASCII diagram above didn't look so good, so here's a picture of the Cross Over Cable.
gobproperty in reply to luberack2 years ago
Do I need to buy a audio 2.5mm jack and then reverse the "tips"--like go to Radio Shack or Frys to do this? This will be a cosmic egg--an attempt at electronics way beyond my comfort level! Can't wait to try it.
for now my Sony A200 is almost nonresponsive--the menu screen activates, but does not trigger the shutter. should this "cure" this issue?
 1-40 of 266 Next »