Monday, November 26, 2012

Controlling Blur In Camera, Not In Photoshop

So, what's the big deal.  If you have a shot where the background is too in focus and the image would look better with the background out of focus, no problem.  That's what Adobe Photoshop (CS6 or before) is for.  That's a hell of an excuse for not knowing what the camera will be doing before you press the shutter.  Today's image is pretty (really) straight for a shot by me.  Just a little touchup in Adobe Photoshop Lightroom 4 (LR4) and it never needed to go to CS6.  A friend and I were out shooting a vintage baseball game during this past summer.  He was using a 80 - 200 F2.8 lens and I was using some 70 - 300 F4.5 - 5.6 glass.  Before the game we did some informal portraits while the visiting team was warming up.  He took a couple shots and said "I can't throw the background far enough out of focus to make things interesting".  Duh!  He had the faster glass and he couldn't get some nice blur????  I turned around to see what he was shooting.  He was about twenty five feet from his subject.  I asked what F-stop he was on.  2.8  Again.  Duh!  What focal length?  200  Double duh!  I looked at his screen and just shook my head.  He had a little blur, but not enough to get that soft background you'd want for a informal portrait.  What was the difference between his shot and mine?  Hit the "Read More" to find out.


The big difference was that he was going for a full length portrait and I was doing a "head shot".  He was 25 - 30' away from he's subject.  I was less than 10'.  He was shooting at 200 mm, I was shooting at 270 mm.  He was at F 2.8, I was at F 5.6.  A full two stops closed down from what he was using.  This guy shoots weddings.  Again ??? 

Let's go to another friend.  She had just gotten her first DSLR.  She had been using a Canon G11.  If you're going to shoot with a "point & shoot", Canon's G series has been the high end since they came out their G series.  So, she had had a pretty darn good camera that she came up from.  She said she'd been working her way through shooting in manual and changing only shutter speeds to see the effect the shutter speeds had on her photography.  Her next step was going to be changing only the F-stops to get an idea what they did.  Interesting experiments.  Once she finishes her testing I hope she will translate that into using Aperture Priority and know what's going to happen with the F-stop she selects.  I told her she had bought a thousand dollar plus computer.  (She said she was still using her old computer and she'd bought a new camera.  I let her know that she had bought a single purpose computer that people referred to as a camera.)  I asked her not to use it as a glorified shoebox.  I recommended she make all the decisions and let the computer (camera) do all the math.  I'm a big believer in understanding what you want in an image, making the decisions necessary to make that image and letting the equipment do the heavy lifting.

Take a look at today's image.  What do you see as a background?  It's the side of a school building with the brick texture stood vertically.  Look again.  You might be able to get a faint idea of what's there.  Selecting the F-stop isn't the only factor in throwing the background out of focus.  Understanding what the camera will do is important.

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