Welcome to my first instructable...

I wanted to make a wired remote for my Canon EOS 400D, and the Canon-Wired-Remote wasn't exactly what I had in mind:
- It had 2 buttons (one for focus, one for taking the shot) and not the 2 step (half press) buttons on digital cameras.
- It was just too bulky (sorry videokid842).

I proudly present the marker-pen wired remote for Canon cameras.
The top button is a two step button (pressing it focuses the lens, and pressing harder takes the picture).
The side switch is for bulb mode, keeping the shutter open for as long as it takes (to create those long to make light drawings).

Step 1: Ingredients

Now, for the stuff you'll need to cook the cake:
- Marker pen (the case for the remote) - should be yellow and shiny :-)
- Empty pen (actually you only need the spring, which you can find in any press-to-open ball point pen).
- Board for doing some soldering.
- Two small (as small as you can find) click buttons.
- Small switch (for bulb mode).
- 3/32" stereo jack (connects to camera).
- Stereo audio cable (in my case, I couldn't find any simple stereo cable, so I dug up this USB cable - see pic).
- Two small metal strips (should be at least about 2-2.5cm long).

In addition you'll need:
- Some tools (screw driver, pliers for bending the strips, sharp cutting knife/xacto knife, etc.)
- Soldering iron and solder.
- Hot glue gun.
- Crazy hot-glue skillz (which I lack -- see further steps, not the cleanest job I've done).
- Patience (ohhh, you'll need it...)

Step 2: Dissection

First things first... we must dissect our ~~alien~~ marker.

1) Take a large screwdriver and use it to pry the top cap off of the pen (using a smaller screwdriver might not cause enough pressure and it may only dent the plastic.
Also, don't put too much force between cap and pen, that might also dent/scratch the plastic cap.

2) Take the bottom cap off and remove the tip of the pen.
I found that hitting the tip on the floor only moves the tip a bit inside, you'll need to hit it with a small screwdriver and it falls down easily.

Step 3: Prepare the Cable

As I've mentioned before, I couldn't find an audio cable, so I tortured this poor USB cable for my needs.

Cut both ends of your cable, strip the wires.
Solder one end of the cable to the stereo jack. Colors are important here, so to ensure no future mix-up, please follow the color coding I've written here:
- Black goes to lowest solder point.
- Red goes to solder point strait ahead.
- White goes to solder point on right.

Test the cable. connect it to your camera and short the white and black cables. This should focus the lens. Now connect the black and red cables and your camera should take a picture.
If everything works, we can continue.

Step 4: Violate Pen With Cable

By now you have a casing and a cable. In my case, the pen opening wasn't large enough to fit the wire and the bottom cap had to be cut as well.

Fortunately by some mysterious design, my cap was built to have a hole punched through it (see pic).
so I had to push the circle it and it just came off.

I Had to use a knife to cut the tip of the pen, so the cable would fit.
IMPORTANT: DO NOT throw the tip you just cut off away, I've used it in a later step.

Step 5: Prepare the Board

Now that we've finished the cable management, we can get ready to do some real work.

Solder the two buttons to the board (in the last row).
Keep at least two holes empty between the two buttons (I used 3), otherwise you might press both buttons together and you won't have a 2 stage button (focus then shoot).
Cut the remainder of the button legs, but do not throw them away, they'll be used soon.

Now you have to bend your piece of metal strip so that it has a flat part, a raised edge (a little higher than the height of the press buttons, buttons included).
Give the metal strip a little downwards bend towards the middle of the remaining straight part.
The first button should be just before the bend, and the second button should be near the end of the strip.
It doesn't have to be perfect, because you'll be tinkering with the shape quite a lot later.

(Optional)
Remember those button legs I told you not to throw away?
You'll have to solder two (or four for extra strength) of them to the flat part of the metal strip. I had to scratch my strip so I could solder to it.
In the end I soldered the strip AND hot glued it to place, so I guess you could just hot-glue it (or use epoxy), but...

(Not optional)
Something must be used to hold the strip in place.

Break the board to the width of buttons. This should also be the width of your case.
I filed the board from both sides, so It'll fit in the marker (not shown in pictures).

Step 6: Connect Cable to Board

By now, your board should look like the first image: you have 4 solder points for the button legs.
You also have a cable with three wires: black, white and red.

What you need to do is connect the black to 2 points on the same side, then connect the red and white cables (red to the button near the end = closer, and white to the button in the middle = farther).
Be careful stripping the wires because the red and black wires should be used also for the switch.
What I did is strip the black cable in 3 parts (near first solder point, near second one and in the end), red in 2 parts (near first solder point and in the end) and white only in 1 part (end, near second solder point),

Solder the wires (black to both buttons on same side, red to closer button, white to farther button).

At this point I tried t solder the black and red wires to the board, put the switch in the board holes and heat it from underneath so it'll stick -- it doesn't work!

What you need to do is to solder the red and black wires directly to the switch, and then glue the switch to the bottom board.

Test, test, test... connect the jack connector to your camera and start putting pressure on the metal strip. The first button should be pressed first, causing the auto-focus to work, then the second button will be pressed and the camera should take the shot.
Now test the switch. The moment you activate the switch the camera should take the picture, and wait in this state until you disable the switch.

Everything works? Good. Let's continue.

Step 7: Fit Board in Pen

Now that you glued the switch, it protrudes from the bottom part of the board, and does not allow the board to slide into the marker.
We have to cut a rectangle in the marker, the size of the switch, so it'll fit there snugly.
Be careful not to cut too much.

Now we have to cut the same width in the top cap, so it'll slide on both sides of the switch.

Fit everything together and admire your handiwork.

Step 8: Firing Mechanism

Currently we have a board and case and need another metal strip to push the first metal strip down, thus pushing the buttons down. Make a little 'bump' in the end of the second strip (belly downwards), so it'll press on the first strip more easily.

Take the spring from the click-to-open ball point pen and attach it to the bent part of the second metal strip. Hot glue them together.

Now glue the other side of the spring to the beginning of the first metal strip, so that the second strip is above the first one, and by pressing on it, the spring contracts and the metal strip slides towards the far end of the first strip.

I glued a piece of plastic I got from a laundry clip I broke, onto the flat part of the second strip. This was to give the strip more height and also to allow it to slide smoothly on the plastic inner side of the marker.

If you look closely at the last picture, you'll see I glued the first strip as well. This is because the solder did not hold very well.

(Optional) If you see there is too much clearance between the first wire and the 'ceiling' of the marker, then you may add some glue to the bottom of the board, near the cable. This will make the board a little higher from the bottom 'floor' in the marker and put the first strip closer to the 'ceiling'.

Step 9: Tinkering

This is the step where most of you will curse me and some of you might even scrap the entire project...

Now we have to start bending the first strip until pressing the second one has the desired effect of focus on half-press and taking the picture on a full press.

This is a tedious work and it took me 2 hours to complete (and I cursed as well).In the end I was about to scrap the project when suddenly I got the right formula and rejoiced.

Basically I bent the first strip, put everything together (in marker), pushed the button and saw if it worked, then took the board out, and reiterated the process.
In the beginning I connected a multimeter to the 3/32" jack, but found out connecting it to the camera was much easier and I could test the focus as well as the shot.
I filled an entire 1GB memory card with the same picture over and over again.

Step 10: Push the Button!

By now you have a board in the marker and by pressing the second strip down, the camera lens focuses and pressing further makes the camera take a picture.

The last thing on the list is to create a button protruding from the top cap.
Remember the little yellow part we cut from the marker and I told you not to throw away?
Well, this is gonna be our button.
First notice where the second strip meets the cap, this is where you need to make a hole.
The marker tip is probably smaller than the square hole you made, so try to trim the sides of the plastic to make it fit the cap.
Be sure not to trim too much in the lower part, because that will cause the tip to slide outside the cap. We want the lower part of the tip to be a little wider, so it will not pass the hole we made in the cap.

The most observant of you fellas will notice that there is a hole in the marker tip and that it feels uncomfortable pressing down on it.
I solved this by putting some hot glue inside the tip and then holding it upside-down, so that at the part where you press a little rounded tip is formed. This feels much better to the touch and also gives the button a nice finish (though it would be nicer were it black).

Assemble the whole thing. You have to make sure the button is not too loose, as it has to be pressed upwards by the spring on the second strip. If this does not happen, you'll need to make your button longer (maybe by adding some more glue on the bottom).

Test it. After the cap is assembled, try focusing and taking a picture using the button, make sure you don't have to push it inside too much, as it might get stuck there.
In addition, you should also check the switch again, make sure we did ruin something.

If all is good, time to glue everything together. Glue the top cap onto the top of the marker (with button inside of course), then glue the bottom cap to the bottom of the marker.

Step 11: Test and Pat Yourself on the Back

Everything is in place, so..... start taking pictures!

Use the top button to first focus then take a picture, use the switch for bulb mode, and take picture of the sky or just draw on the air using light.

You've done a terrific job, so pat yourself on the back and go have a refreshing drink.