Bokeh Lesson from a patient Bee . . .

[RussHeath]

My recent thread in the macro section, titled Bokeh Bee, has prompted a little discussion. On a recent hike to Lost Lake near Vail, Colorado, I encountered a very patient bee and learned quite a bit about what makes good bokeh.

So what is bokeh? There are many definitions, but the one that I like is this: Bokeh is the quality of the out of focus portion of a picture. If this makes complete sense to you feel free to quit reading now. If you're still a little fuzzy, read on.

While walking along the trail I encountered a very still bee on a yellow flower. I had my D80 over my shoulder with my trusty 18-55mm f/3.5 - 5.6 kit lens mounted. I doubted that he would hold still for long so I quickly crouched down and shot this:



55mm, 1/60 sec, f/5.6. Not my favorite picture, but maybe if you crop in close and sharpen quite a bit you'll get a nice photo of a bee. Notice that the out of focus portion of this picture is not very out of focus. In other words, you can easily discern what is behind my subject. The thoughtful little guy actually held still, so I tried again and got this:



55mm, 1/60 sec, f/5.6. Same settings, but a better picture. Why? I got closer to the subject.

Lesson #1) Getting closer to your sujbect improves bokeh.

You can see that the out of focus portion is more blurry, allowing the main subject to stand out better. I know the framing is different, but even if you cropped the first picture (feel free to do this) and compared at similar framings, the bokeh is better in the second photo.

For some reason, he still hasn't moved. So let's try again:



55mm, 1/30 sec, f/9. In an effort to get more of the bee (and flower) in focus I "stopped down" or decreased my aperture which, in my program mode setting, also increased the shutter speed to let about the same total amount of light in. What effect does this have? More of the subject is in focus, but the bokeh is worse!

Lesson #2) Larger apertures (smaller f/numbers) make better bokeh.

Maybe it's time for me to talk a little more about what bokeh is and is not. Bokeh IS subjective. Bokeh IS NOT something you can test on a test-chart. That's why great sites like SLRGEAR don't include it in their ratings.

So who cares about bokeh? Portrait and macro photographers primarily. Anytime where you want to have a simple subject (which should be most photos in my humble opinion) there is need to isolate a subject from it's background. There is no such thing as "right" or "wrong" bokeh. It's subjective.

So what do most macro and portrait photographers strive for? Neutral bokeh. In my simple mind that means the smoothest and most featureless out of focus area of a photo as is possible with the given scene. My ideal bokeh (yours may be different) is a completely smooth blur of color behind a clear, sharp subject.

So what goes into making bokeh? Well, I've already mentioned two things. Read on for more of my not-so-insightful insight regarding this topic!

(Apologies to all for needing to reply to my own post, but I can't do this in the 4 pic constraint so I'll split it into 3 and 3.)

[RussHeath]

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.

[Palachandra]

I heard about the word "Bokeh", but never tried to figure out what does that means!!!

newbie, thanks for the demo and explanation!

[RussHeath]

Palachandra -- You're very welcome.

[ELAY]

Outstanding.

I have to say that the whole longer focal length=better bokeh thing has always puzzled me. For me, I think of bokeh quality improving as the ratio of camera distance to subject/subject distance to background decreases (ie. if I am one foot from the subject, a and the subject is ten feet from the background, I get better bokeh than the reverse). I sort of get that a longer focal length will have a foreshortening effect, but if it entails backing off at all for framing it seems to me that you are going to be upsetting the ratio. Not such an issue for macro photography where you typically aren't going to be backing out, but it is an issue for portrait photography where you wander around a bit. Hmmm.

The only thing I would add to the above is a small point re points of light bokeh. If you shoot with your lens wide open (smallest f/stop), you lose the geometric shapes on points of light created by your aperture blades, and get a circle (because your blades are out of the way).

EL

[Isilwen]

Thank you for that tutorial! I had figured out through reading what Bokeh was but had no idea about the specifics. I found myself wondering about the bee by the end (thought he may be dead too) so thanks for the update!

[wulf]

Two more thoughts about bokeh:

1. Characteristics vary from lens to lens and from setting to setting on a given model. Working with advice like that above to get you started, there is no substitute for exploring how it works with your own equipment.

2. Another big factor is light and colour in the background. Here it is a fairly dark and neutral setting, which looks like a photographers backdrop; often there is more light and colour which can either add further magic or detract from the main subject.

Wulf

[RussHeath]

Originally Posted by ELAY

Outstanding.

I have to say that the whole longer focal length=better bokeh thing has always puzzled me. For me, I think of bokeh quality improving as the ratio of camera distance to subject/subject distance to background decreases (ie. if I am one foot from the subject, a and the subject is ten feet from the background, I get better bokeh than the reverse). I sort of get that a longer focal length will have a foreshortening effect, but if it entails backing off at all for framing it seems to me that you are going to be upsetting the ratio. Not such an issue for macro photography where you typically aren't going to be backing out, but it is an issue for portrait photography where you wander around a bit. Hmmm.

The only thing I would add to the above is a small point re points of light bokeh. If you shoot with your lens wide open (smallest f/stop), you lose the geometric shapes on points of light created by your aperture blades, and get a circle (because your blades are out of the way).

EL

Elay -- I'm glad you liked it. Your observations are important ones, too. This is definitely a limited tutorial which applies most directly to macro. Portrait photography has it's own unique set of issues.

The whole focal length thing may not hold up in all situations, but if I'm 1 foot from a subject which is 10 feet from it's background and I shoot from that same spot with a 55m vs a 105mm, I think I will usually get better bokeh with the 105mm. It may not be a fair comparison, however, because if you had the 55mm you may just move closer.

Thanks for the addition about points of light becoming more pleasing circles at wider apertures. I had not realized that, and it would be important when shooting portraits.

[RussHeath]

Highbrassduo -- You're welcome! As you can see from the rest of the conversation here, my "lesson" is certainly not a complete overview of bokeh, but it will provide some basic guidelines for shooting macro.

Originally Posted by wulf

Two more thoughts about bokeh:

1. Characteristics vary from lens to lens and from setting to setting on a given model. Working with advice like that above to get you started, there is no substitute for exploring how it works with your own equipment.

2. Another big factor is light and colour in the background. Here it is a fairly dark and neutral setting, which looks like a photographers backdrop; often there is more light and colour which can either add further magic or detract from the main subject.

Wulf

Wulf -- I couldn't agree more. My favorite thing about this exercise is that I didn't plan it. This was just a natural progression that occured while I was out shooting and experimenting with my own gear. Experience will always be the best teacher!

[phlyersphan]

Thank you very much - your explanation and examples have been very helpful!! *bookmarking now*