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Old 09-07-2007, 04:14 AM
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RussHeath RussHeath is offline
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Join Date: Feb 2007
Location: Colorado
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Lightbulb Bokeh Lesson Continued

At this point I'm starting to think the bee is dead. So what do I do? Change lenses of course! I switched to my 105mm f/2.8 Macro VR lens (with all those letters it better be good). Here's the first shot off the camera with my favorite lens:



105mm, 1/50 sec, f/5. In my very humble opinion, this is bokeh perfection. Pure, smooth, blurred color behind a sharp subject. If you'll notice, f/5 is very close to the f/5.6 shot with my 55mm close up. So why is this wonderful bokeh and that shot was so-so?

Lesson #3) Longer focal lengths create better bokeh.

Why? Because they exaggerate the difference between near and far subjects. This is exactly what you're after when trying to make a lone subject stand out of a background. It does, however, make it very hard to shoot landscapes with this lens! (For the same reason).

So we're done, right? Not quite. If you zoom in to 100% on this shot you'll notice a dirty little secret when it comes to bokeh: long focal lengths and wide apertures (small f/numbers) that make for great bokeh can result in extremely shallow depth of field (especially in macro shots). Even though the bee's eye is in sharp focus, the hair and pollen on the far side of his body are a little out of focus. Maybe this could be patched up in photoshop, but lets try once more to do it the old-fashioned way:



105mm, 1/15 sec, f/13. Better bokeh? No -- while it's still a lot better (in my opinion) than all the shots with the 18-55 at 55mm, there is the vague suggestion of shape behind the bee. So, not quite as good. Then why do I like this picture better? It's the best compromise of the whole set. Bokeh is very good (not excellent like the previous shot) but what I gain is that the entire subject is in sharp focus.

Lesson #4) Nothing in life is free. Everything is about tradeoffs.

So this final shot, which is an edit of the last one above, is my public offering on flickr and in my recent macro thread.



All I did was crop to put his eye in a pleasing "rule of thirds" intersection, increase the saturation of yellow, and run a high pass filter at 30% -- Did you think I had something against photoshop?

A word about diaphragm blades:

Many camera store salesmen and internet heroes will prattle on about the benefit of having more diaphragm blades in your lens and what an amazing effect it will have on the bokeh. The only time this comes into play is when you can see geometric shapes rendered as points of light in the out of focus portions of your shots. When used for portraits, this may play a bigger role, but as I've hopefully shown here this has little bearing on bokeh for macro photography. If you can clearly see the geometric shapes caused by the shape of a camera's diphragm then A) you might notice a more rounded shape if you have more blades (My 105 has 9 compared to my 18-55 with 7) and B) you need to increase the quality of your bokeh another way if possible. See lessons 1-3.

That's it! Lots of text to explain a simple idea. Please remember the above are only my humble opinions and work well with my style of photography. Feel free not to agree. That's what it's all about.

For those of you still reading who might be wondering the fate of the bee -- he climbed up on top of the flower just as I was finishing. How thoughtful of him not to move earlier! I think he was just damp and was so still because he was drying out.
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Nikon D80, 18-200, 105 macro VR, 18-55, 50 f/1.8; Tokina 11-16 f/2.8
SB600 x 2; Canon A570 IS; Bonica XP Neon Underwater Strobe
Film Cameras: Lomo LC-A+, Diana+, Canon AE-1

OK to edit and repost pics for DPS forums!
flickr; ihardlyknowher; My most interesting pics on flickriver

Last edited by RussHeath; 09-07-2007 at 04:54 AM.
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