Ambient Light-the existing light that you cannot control

Stop-measurement of exposure by a factor of 2. One stop more doubles the light. One stop less reduces the light by half.

Exposure Triangle-the interchangeable association of ISO, Aperture and Shutter Speed

Strobe Basics

Strobe Lights or Flash-The exposure triangle does not hold because the shutter speed is effectively replaced by the flash duration. We adjust the exposure primarily with the aperture or the ISO.

Sync Speed-is the fastest shutter speed for which the shutter curtains are completely open at the time of exposure (or when the flash fires). For shutter speeds above sync speed, the shutter curtains are no longer fully open.-Dpreview.com

Flash duration-a measurement of the length of time of the burst of light that makes the exposure. This is how long the light is actually on. With our Dynalight strobes this is about 1/450th of a second at full power. Canon speed lites are about 1/313 at full power but 1/4,950 at 1/8th power

The sync speed of the class cameras is 1/200. To get around this, use: 

High speed sync-allows the camera to be set at shutter speeds higher than the camera sync speed 

DO NOT fire the flash in huge bursts when using high speed sync! If the flash becomes hot, let it cool down before using again.


ETTL (Evaluative-Through The Lens) is a Canon EOS flash exposure system that uses a brief pre-flash before the main flash in order to obtain thlo 7 `e exposure.

M-Manual-Set the power of the flash to full power, 1/2 power, 1/4 down to  1/128 power. The difference between each setting is one stop.

Zoom-you can spread the light over the scene or focus it by setting the zoom. A number that corresponds to a wide focal length like 28 mm will spread the light. A number corresponding to a telephoto focal length like 200mm will create a narrower beam of light.

Exposure-For consistent results use M shooting mode.
1. Figure out the exposure without the flash. If you want shallow depth of field use the widest aperture then figure out what shutter speed you need. On a bright sunny day, you should be able to shoot at 100 ISO. 

2. Stop down one or two stops depending on the look you want. 

Off-camera Flash

Put your flash on the channel that matches the trigger and receiver.

SAAF-Shutter Ambient, Aperture Flash

Shutter speed will control the illumination of the background.

Aperture will control the illumination of what is being lit by the flash.

Make the shutter speed faster to make the background darker when shooting with flash.



Main Light

Make a minimum of 10 portrait photos using off-camera flash as the main light.

Fill Light

Make a minimum of 10 photos with flash as the fill light.

Post your 20 best to Flickr and send the best of each one to the class group.


May 17th. 4 pts. Topics include portrait photography, flash-on and off camera.


Final project

Shoot 2 is due May 17th.

All the World Photo contest

Due on May 17th

The contest submission consists of three portrait photos, a short bio of 100 words of each subject and a photo release form for each one.

Put a small jpg with your 100 word bio for each subject on Google Drive and share the document with me: robinmichals@gmail.com before noon on May 17th.

Due on May 24th

Your final submission including the three photo releases and proof of submission.