This week we learned how ambient light sources affect our image when using studio lighting.

For the first section of the exercise I tested the lens at its widest aperture and simply adjusted the shutter speed to see at what exposures I was seeing any ambient light. I had all of the overhead lights on and you can see that even at 1/1000 of a second there is still some ambient light affecting our image.

Now I left the lighting the same but kept the shutter speed constant and changed the aperture for each frame. As you can see that f/22 we can cancel out all of the ambient light. If I could not turn off or had to control to eliminate the ambient light f/22 would be my choice.

With the overhead lights still on I added a strobe and set it to its lowest power and while keeping the aperture constant I adjusted the shutter speed. Now that I am using the flash strobe, the direction and temperature of light has changed compared to the first set of images and the light is more direct. Also, note how as shutter speed is increased the light gets darker but the ambient light stays constant.

Now with the ambient light turned off and I am only using the strobe, the light is more uniform and some of the lights that had been visible and gave unsightly reflections have been eliminated. In addition, I now have total control over the light, which doesn’t change because the burst of light is constant. Once I push the camera past it’s fastest sync speed we will lose that light and end up with what the last frame is.

Here I set the shutter speed to 1/125 and adjusted only the aperture with the strobe on the lowest setting.

As I adjusted the aperture you can see the data represented on the histogram shifts further and further to the left, signalling that I am starting to underexpose my image more each time I stop down.

I set the strobe to maximum power and followed the same method as before. It seems that f/11 looks like the best exposure. I noticed any surfaces nearby that could reflect anything were more prominent using such a high power.

Now here I am practicing maintaining consistent exposure through the power range of the power pack that the strobe is attached to.

Here I have adjusted the power of the light while using a constant setting of f/2.8 @ 1/125.

For the final set of images, I adjusted the power of the light while using the narrowest aperture f/22 and a shutter speed of 1/125.