09/21/14

Low cost laser barrier Photography

_MG_9916-2

After trying to capture an exploding water balloon with a very rudimentary method (see here), I dedided to try again but using a low cost laser barrier and a LDR (Light-dependent Resistor) to get more accurate results.

Materials:

  • 1 Laser diode (5v, a pack of 10 is very cheap on eBay).
  • 5v Power supply (or 4xAA batteries) for powering the laser.
  • 1 small LDR (Light-dependant Resistor)
  • 100K variable resistor
  • N3 camera connector (Canon 5D) or minijack depending on camera model.
  • Bag of water balloons
  • Also a flash is necessary to freeze the motion, and also using it at the minimum power possible.

Circuit:
 
Knowing that to shoot the camera with an external cable we need to short-circuit two wires (Shutter and Ground), I put a 100K variable resistor between the two wires and saw that the camera shoot when I set the resistance lower than 25K.
Once we know that resistance, we know that if the sum of the variable resistor + LDR is < 25K, the camera will shoot.
To build the circuit I just put the LDR and the variable resistor in serial and then connected them to the shutter and ground cables of the camera. The variable resistor serves to callibrate the initial status and set the camera to a point that almost shoots. Then, when we point the laser to the LDR, its resistance lowers and the overall resistance between the Shutter and Ground cables will be < 25k, so the camera will shoot. In normal conditions, when the water balloon is in front of the LDR, the camera won’t shoot because the LDR resistance is too high to trigger the camera. When the water balloon explodes, the laser beam will illuminate the LDR.

Camera and flash settings:

  •  Shutter: 1/125 (if there’s ambient light it should be faster).
  •  Lens focus set to manual.
  •  ISO 400
  • Apperture: f/8-f/12 to get enough DOF.
  • Flash power set to 1/64 and zoom at 105, about 60cm from the water balloon (on the left). Also, the flash is triggered from a remote emitter in the camera.

Once all is prepared, we just have to tie a water ballon to the rope so that it is placed between the laser and the LDR, and when we make the balloon explode with a needle the camera will automatically shoot.

Original idea:

20140921_191817

Setup and circuit:

20140921_154954 20140921_155034 20140921_155136 20140921_155223 20140921_174249 20140921_180640

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
Results:

_MG_9912_MG_9918

 

 

 

 

 

 

 

 

 

 

 

 

Notes:

  • I built the same circuit with a LDR of a greater size and it didn’t work so well, so I recommend using a LDR of the same size as the laser point if possible.
  • I noticed a significant delay between the balloon exploding and the camera shooting, which I didn’t find so slow in my old Canon 40D. To solve this I recommend setting the water balloon higher than the camera frame, so that the balloon doesn’t appear in the frame until the water balloon falls.
06/12/14

Making of “Ephemeral dreams”

To create this work, I mixed a 3D rendered labyrinth with some photos. The final photo is composed by these three kinds of images, created in this order:

Hands: I used a Canon 17-40L lens at 17mm, f/20 to get a lot of dof and flash on the right with a small softbox.

hands_setuphands

 Sand falling:

I needed to get some photos of sand falling and merge them together to create the parts where the labyrinth was melting. My photoshop skills are very limited so I had to get a good perspective and shoot at 17mm too in order to facilitate the edition. I did some tries using a shutter speed of 1/30, also f/20 and natural light to get a kind of “silk effect”, but when I joined the captures with the 3D labyrinth, the result looked like plastic. I repeated the sand captures using flash to get the opposite appearance (freeze the motion), and I stuck with that setup for the rest of the photos I needed (just 3 or 4).

sand_setup

sand

 

 

 

 

 

 

 

 

 

Labyrinth: Modeled with 3D Max 2014 with iray. First I created in Photoshop a 2D image in black and white with the labyrinth I wanted, until I got this:

plantilla_laberint2

I added some layers and used the gradient tool to darken the corners so that the labyrinth appeared that was melting when applying later the “displace” modifier in 3D Max (depending on the shade of gray, the height of each wall will differ).

Then in 3D Max, applying the modifier “displace” I used the displace map created to get the 3D appearance. With the modifiers melt, noise, wave and bend I added some imperfections, and also edited the mesh of the labyrinth to melt much drastically the middle part and the sides. Result:

laberint_high_low_mid_fused

Each part was processed with Lightroom to add some dramatism by using clarity and blacks, and changing the temperature of the captures, and also desaturating to have a similar appearance in all of them and facilitate the Photoshop part.

Final photo:

02/13/13

Light Painting Wireframing tool

The idea:

Create a tool that projects a laser net to combine with the Light Painting photography technique, so that when projecting this net over a scene, it “seems” to be a wireframing view of a 3D modeled scene.

Solution:

Using only one laser pointer, create a set of horizontal and vertical lines that combined with the photo long exposure will result in a laser net. The laser pointer is moved by two RC servos controlled with a PWM signal generated by a 16F876A PIC microcontroller.
Once the circuit is done, the program can be configured to change laser speed, offset between lines and net size.

For the video I used a 7.4V LiPo battery, the voltage is regulated by a 7805, and the laser pointer uses one of the PIC 5V outputs with a 25 Ohms resistor.

Demonstration video with photo samples:

 

 

07/30/12

State of Your art: What makes an artist improve?

Paths to consciousnessHow many times can you overcome the same challenge feeling the satisfaction you had the first time? Some people only need one or two times, others can keep repeating the same thing for a long time and still enjoying it. This number will depend on our degree of demand and perfectionism, which in practice is the time that takes us to need a more complicated challenge, and see what we’re capable of. That’s why I think artists or professionals learn and get results at different rhythms.

From my experience, the learning curve is based on what I’ve just mentioned and two more factors that I’ll explain now, but in a different perspective than the typical “learn, practice, learn, practice”. What I find more interesting is what do we think about the results we’re getting. Are they good, bad? Are we proud of them? Which aspect would have a better result?

The first and more important factor is what I call State of Your art. If you were asked to position your work in a “quality ranking” among everything you know about that subject, where do you think it would be? You’ll probably think there’s a lot of people already better than you at that, and still more if you’re just beginning, but knowing the State of Your art will allow you to have an imprecise but also global reference, and wou’ll not be disappointed when you find out somebody else had the same idea as you and executed it in a much better way, or with a slight difference that you wouldn’t have thought of. Knowing the State of Your art won’t give you so much satisfaction when creating something new, but neither you’ll be disappointed if you discover that your idea was already done, because you already knew that this could happen.

How do you know your position in the ranking? Suppose there’s still a lot to see, that there’s somebody better than you, and that you still have a lot to learn. Thinking this way won’t give you an exact position, but I believe it’s an appropiate attitude to have. I find interesting and useful to read and talk with other professionals, to see how they work and also to learn and inspire myself, but I also think it’s important to develop a personal style that, while being influenced by some others’ works, are the product of our vision as an artists and professionals.

The second factor which I find necessary to improve is self-criticism. Just before creating something, many times comes the initial euphoria of “This is amazing!”. It’s fine to feel this way at first, but then it’s necessary to place your new work in the ranking of what you know and settle down.

I think the previous factors allow us not only create better art, but also better products and services, as long as exists a continuity and passion in what is being done, without thinking about getting huge results, just to improve, do someting meaningful and setting personal goals, the rest will follow.

08/21/11

Consuming art to create art

Since I started doing music, photography and other arts in which I’m interested, when I asked some people for advice at the start, the typical answer was “draw/listen/copy/play someting you like”. I think that trying to imitate a reference artist can be useful and motivating in the beginning to learn some technique, but what happens when all your education is based on learning that way?
Old music sheets
Learning classical piano for example, the common denominator of most schools is that they teach you how to read sheet music gradually, to be able to play more and more dificult songs, songs which most of them were composed two hundred years ago, isn’t there any good classical piano composers at present? Things are quite different in modern music styles like Jazz or Blues, where an significant part of the song isn’t in the paper but in the artist, this forces the interpreter to contribute with a personal expression to the song. Due to this “extra” effort we do have some brilliant Jazz musicians at present, Brad Mehldau for example. I don’t pretend to say that modern styles are for most talented musicians, I just think that some existing (and extended) teaching methods don’t maximize the creative abilities of the artist.

This has happened to me for example, when I try to create a new song, half of the time I have an idea I’ve thought “Cool! Wait a minute…”, and then I realise that that melody was from a soundtrack I listened a year ago. Is it really valuable having listened and learned to all that songs or technique when talking about creating something new? I think it happens the same with photography. In my opinion is like wanting to build a castle with those wooden pieces games, if you have the pieces in front of you, you will build only with that pieces, but if you start with no pieces but you still want to build the castle, you’ll find something to replace them, don’t be afraid of not having the proper education or knowledge about an art, because in my opinion all of that is less important than curiosity and attitude.

What is also interesting is that if you can play a Rachmaninoff concerto you’re a genius, but if you draw a copy of a Monet’s painting, this is not so amazing at the eyes of another artist, to be euphemistic, so innovation is more or less important depending on the art we’re talking about, and I’m not sure if this makes any sense.