OCA Photography Learning Log: Exercise 1

Project - Getting to know your camera

Exercise - Focal length and angle of view

This is the first exercise of the first project in the course which focuses on getting to know your camera. I like to think that I know my camera pretty well, but some of this exercise really surprised me.

The first step is to find out what your camera's standard focal length is. This is achieved by looking through the viewfinder with the right eye whilst keeping the left eye open. By doing this you can get the real image and lens image to match up. I was surprised to find that on my 17-50mm lens, 50mm was the "standard" focal length (figure 1). However, my camera is not full frame (it's a Canon 7D), so I was expecting it to be about 30-35mm. I checked this with my 50mm lens and it too was "standard". I'm a bit confused by this so I'm going to put a post up on the OCA Forum and see if anyone else has found the same result.

I don't have anything higher than 50mm, so I opened up the lens to it's widest focal length (figure 2), and then put on my 10-20mm and took a shot at it's widest (figure 3).h

The next step was to print each shot (however, I decided to put the photos onto a tablet device which is roughly A4 size), and then return to the same location. I then held the photo up in front of me and matched it up with the real world image.

For figure 1, I held the tablet at roughly the same distance as I would usually hold the device. For figure 2 it was just a few cm and I couldn't get the tablet close enough to my eyes (whilst still being able to see the image), for figure 3. Obviously if I had a telephoto lens I would have had to have held it further than arms length in order to get it to match up.

Observations & Learnings

In addition to the surprise that my camera has a 50mm standard focal length. I also experienced a bit of embarrassment at standing in my street taking photos of nothing and then later standing with a table in my hand. I'm not pointing this out as humour, but rather as a note to myself that I need to get over this if I'm going to be able to progress as a photographer.

It was also interesting to start to think of the lens as simply moving a frame back and forth through the space in front of the eye in order to determine what to capture. This exercise may make it easier to start seeing the world through a virtual lens in order to visualise what will make a good photo.