Category Archives: Photography

Bulb/Shutter Button for Canon T3i Cameras

After a few attempts at taking bracketed photos using a crappy tripod, I’ve decided that I either need a better tripod or a bulb. Since I can build a bulb for a lot less than a decent tripod, that’s the route that I am going to choose. It only takes a few parts, and can be put together in under an hour. My total cost was <$9.00 because I had the box and the wires, but you could probably make it for less than $20 if you had to buy the box and the wire. You could save a little by scrounging wire from old electronics or a dumpster. Honestly, save money on the box, too, and just use a mint tin.

Parts Needed

  • 275-1571 — 2 pack of SPST momentary switches
  • 274-244 — 3/32″ plug
  • Small project box (like a 270-1802 — 4″x2″x1″)
  • Three pieces (2-3 feet) of small, stranded wire (smaller than 20AWG)
  • Tools like strippers, soldering iron, solder, wire cutter, drill bits, hot glue…

Schematic

How To Assemble Shutter Bulb/Button

  1. Do a dry layout of the buttons in your box to make sure they fit.
  2. Drill two holes for your buttons.
  3. Drill one hole in the front of the box for your wires.
  4. Install your buttons in the box.
  5. Strip three pieces of wire for the length that you want your remote to be.
  6. You’re going to have to fit the wires inside the tiny plug body…
    Solder one end of each wire to a contact of the switch. One wire per contact.
    Attempt to close the body. If it closes, yay…if not, make it work. I did it with 20AWG. It barely closed.
  7. Once you have the body of the plug closed, slide the o-ring over the end.
  8. Now, I braided my three wires. You do it how it pleases you. I don’t want wires flopping everywhere.
  9. Insert the wires into your box.
  10. The wire that is soldered to the sleeve of the plug is connected to both switches.
    Solder that one wire to one contact on each switch. It doesn’t matter which tab. Just don’t solder it to both contacts of one switch.
  11. The wire that is soldered to the ring of the plug (the middle contact of the plug) is the AF. I soldered this one to the black button. Solder the end of this wire to the remaining contact of the black switch.
  12. The wire that is is soldered to the tip of the plug fires the shutter. I soldered this one to the red switch. Solder the end of this wire to the remaining contact of the red switch.
  13. Zip tie or hot glue the wires where they enter the box to keep them from being pulled out.
  14. Close the box if you think you did it right. If you want to test it first then go to 14.
  15. Test it on your camera to make sure it works. If it does, go to step 13. If you already did 13, go take pictures.



*notes that you probably needed to hear at the beginning:
Make sure you label your wires OR have a DMM around to check continuity before braiding your wires. This will make wiring your box easier.

ISO effects on image quality (using a Canon T3i)

Below shows the effects of varying the ISO on my Canon T3i. I should have had the camera on a tripod to do this, but it gives you a pretty good idea about the ISO settings on the camera. The higher the ISO, the lower quality the photos become. I like the quality up to about 400. I could probably live with ISO 800 in better lighting. The door shot shows a lower lighted area. The curtains are much brighter and look okay at higher ISOs.

ISO from the Canon T3i

 

Depth of field – quick memory cheat sheet

Image courtesy of http://www.dofmaster.com/dofjs.htmlDepth of field is something that is fun to play with. It can help you create stunning photos when you have control over your depth of field. Sometimes I have a hard time remembering how to narrow the depth of field, but there is a simple way that I try to remember. I had to write it down, and I think I have it now. While there are calculators out there for figuring this stuff out accurately, at this point I’ll happily live within the realm of “close enough.” In my electronics studies, I like to live in the “10% rule” as suggested by the book “The Art of Electronics” by Horowitz and Hill.

In photography, there is a lot to know, and I am not going to proclaim that I am an expert. There are those with educations in photography that can tell you much more about how things work. For me, just knowing what the results will be is good enough. If you want to know the math behind all of this, there are great and popular sites that can help with that.

Depth of field is controlled by three variables: focal length, f-stop, and subject distance. Two of these are proportional to depth of field: f-stop and subject distance. Focal length is inversely proportional to the depth of field. Finally, I’d like to note that an increasing f-stop number is equal to a decrease in the aperture.

an increase in focal length = a decrease in DOF
an increase in f-stop = an increase in DOF
or
a decrease in aperture size = an increase in DOF
an increase in subject distance = an increase in DOF

Now, it’s a great time for some examples…

Penguin poses for focal length experiment

Increasing focal length decreases DOF
Decreasing focal length increases DOF

Penguin poses for f-stop experiment

Increasing f-stop (wider aperture) increases DOF
Decreasing f-stop (narrower aperture) decreases DOF

Penguin poses for subject distance experiment

Increasing subject distance increases DOF
Decreasing subject distance decreases DOF


Mr. Penguin poses one last timeI’d like to add that you can create some extremely shallow depths of field by having a large focal length, small f-stop (large aperture), and be as close to your subject as the lens will allow a focus.

This image was taken inside with a flash with the subject being less than 3 feet from my desk. You can see that the depth of field is so shallow that even Mr. Penguin begins to blur as his body slopes away from the camera. The opposite holds true if you decrease the focal length, increase the f-stop, and increase the subject distance. Ignoring the focal length and subject distance (assume you have a prime lens and you can’t change the distance between you and the subject), the following phrase is for you: “f/8 and be there” – Arthur “Weegee” Fellig.

How to make time lapse videos with a digital camera

Nothing is more rewarding than watching something that took hours to unfold in a time frame of a minute. I once thought that making time lapse videos was impossible, but I’ve recently found a way to do it that is so easy you’ll want to time lapse everything.

You’ll need a few items to do time lapse:

  • A digital camera (a web cam would also work)
  • A tripod
  • A computer (I use Linux/Ubuntu and MENCODER. Windows and FFMPEG is also out there, but not referenced here. Sorry.)
  • Time (because this method requires you to push the shutter button a lot)

Gathering this equipment isn’t a big chore. Finding something to time lapse shouldn’t be either. For fun, start with clouds. Find a nice field or opening because it is better if you can have a deep depth of field.

The night before you should charge your batteries. If you can change batteries while the camera is on the tripod, you should be okay. Many cameras do not have this luxury, and without an AC adaptor, you’re stuck with playing until the camera batteries die. Starting out, you may only want to take a few pictures a minute if this is your case.

You’ll also want to make sure that you have enough room on your memory card. Back up your images and wipe the card clean. Formatting the card in your camera might also be a good idea. I’ve found that deleting the files from a computer doesn’t always clean the memory card up. While you have your card in the camera, make sure you use a sequential file name sequence.

On the day of your shoot, mount your camera on the tripod and position it where you want it. I usually use the “point and shoot” setting on my camera so I don’t have to worry about exposure time. As you get better, you’ll probably start to mess with those manual settings.

Pick a time frame to shoot. My first video was taken at 6 frames per minute. Every ten seconds I snapped the shutter. This is a good time to kick back in the lawn chair and prepare to spend some time outdoors. Wear sunscreen.

Once your images are captured you’re going to load all your images onto your computer. Most cameras should have named your files in sequential order starting at zero. If it didn’t, you have a lot of work ahead of you. You’re going to need to find someone with a script or program to rename them. Chances are good that your camera did a good job and named them correctly.

Now, all you have to do is open a movie editing program and load all ten thousand of your images one by one into….just kidding. There is a program called MENCODER that will do all the work. I open a terminal window and go to the directory where my images are located.

robbie@ubuntu:~$ cd /home/robbie/folder_name

Next, I issue this command:

robbie@ubuntu:~/folder_name$ mencoder mf://*JPG -mf fps=24:type=jpg -ovc lavc -lavcopts vcodec=mjpeg:vbitrate=2400 -vf scale=768:576 -oac copy -o video.avi

You should see your frames being created right before your eyes in the terminal. You can practice with just a few frames to see how it works. Just snap a few hundred pics quickly and give it a run. You’ll find it very enjoyable.