Kamloops professional photography tips by Kelly Funk: Lesson 2-Shutter speed

After a fantastic weekend of workshops and a brilliant bunch of participants that did incredibly well; oh ya, and that terrific Canuck’s win over the Blackhawks 😮 it’s time for another blog entry.  As promised this will encompass perfecting exposures and how shutter speeds work in correlation with apertures.  Last week we discussed the basis for choosing a certain aperture.   In manual mode (this is how I teach and with static subjects always use this mode myself to have total control) there is what’s called an ‘exposure indicator’ at the bottom of your viewfinder, or the back of the camera’s LCD, whichever method you’re using.  Adjust your shutter control dial until the movable cursor is right in the middle of the exposure indicator line.  This is the camera’s metering system telling you that this is a ‘perfect exposure’.  Problems arise however when the camera’s metering is tricked by hightlights, shadows or generally contrasty exposures.  Make no mistake, today’s cameras do a wonderful job overall of giving you the correct exposure but they can still be tricked.   After making the shutter speed adjustment, take a picture.  NOW, check your histogram. 

See the histogram on the right of this raw file.  This is a very good histogram.  The histogram is how we determine a proper exposure, not by looking on the back of the LCD !!  You want to get as close to the right hand side of that graph as possible to negate brightening up images in your software program.  Why? Because that induces noise, or grain and degrades the quality of your images.  So, after you take your initial shot you may need to make shutter speed adjustments.  If you click on this image you can see my final shutter speed was 1/100 sec.  I know from the shoot that the camera’s metering was close but I had to overexpose slightly ( or slow down the shutter speed ) from the camera’s initial suggestion to reach my final shutter exposure.  Sometimes I may take 5 or 6 preliminary shots before beginning a shoot to reach that optimal exposure.  So, to recap:  Choose an aperture based on your creative intent, ie. how much depth of field do we need etc. Adjust your shutter speed using the exposure indicator at the bottom of your viewfinder.  Take a shot.  Check your histogram.  Make shutter speed adjustments if needed, keeping the graph as close to right side as possible but not butting up against it (this will result in blown highlights and information loss.)  You now have a perfect exposure!

Examples of purposefully under and overexposed histograms from the above raw image:  Top (underexposed) Bottom (overexposed).

To correct for underexposure: Slow down your shutter speed. ie. if you start at 1/125 sec, try 1/60 then check your histogram again.

To correct for overexposure: Speed up your shutter speed, then check your histogram.

Of note: Students often ask about the shape of the histogram’s graph.  Never worry about the shape, you have no control over that, only that you’re as close to the right (highlights) as possible without butting up.

Addendum:  A couple of people have asked how the girl is exposed so nicely with all the contrast between the background and the foreground.  Well done!  The girl is actually lit by 2 speedlights (to my left) but at this stage I don’t want to get into this, I only want you to be concerned with that all important histogram 😮

Join me next week for another installment of professional photography tips.  If you have any questions or would like to see more of my work go to my site here

Cheers, Kelly

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~ by Kelly Funk Photography on April 18, 2011.

2 Responses to “Kamloops professional photography tips by Kelly Funk: Lesson 2-Shutter speed”

  1. Hi Kelly,
    Great explanation on how to use the histogram to get a correct exposure. Very easy to understand how it relates to shutter and aperature. Thanks to you, I will not be leaving my Manual mode:)Look forward to seeing more of your lesson tips:)

  2. I did believe you when you explained that the LCD monitor couldn’t be trusted for exposure. I just didn’t think it would make a big difference.
    I took two wide-angled shots of the stream from the workshop. One was exposed according to the camera’s suggestion. On the LCD screen, it looked good. I exposed the next shot according to the histogram. In the LCD screen, it looked too dark.
    Then I printed both images and compared them. The second image is ten times better! The difference is amazing. This was an tremendously useful tip! Thanks!

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