Bad Bokeh?

Can anyone show me the difference between a photo with a good bokeh and one with a bad bokeh. I'm not sure that I know the difference. I guess I'm still trying to get the subject to look good and haven't paid much attention to the background. I apologize if this is a dumb question.

I don't have any samples to show the difference but you have to keep in mind the fact that the quality of bokeh is subjective. One person's bad bokeh is another's perfect bokeh.

Bokeh is very subjective, but here goes:

Here's my opinion of good bokeh (85 f/1.2L MKII on a 5D):

Mark_Cohran wrote in post #4022409
Bokeh is very subjective, but here goes:

Here's my opinion of good bokeh (85 f/1.2L MKII on a 5D):

Note the smooth background and the circular uniform hightlights.


Mark

I must say, I don't think this the best example of "good" bokeh. Leafless trees seldom result in good bokeh, as can be seen in this example taken with a camera/lens combo reknowned for its great bokeh.

My example of bad bokeh.
You can see those nasty pentagon shaped bokeh.

Dannydoo wrote in post #4022555
My example of bad bokeh.
You can see those nasty pentagon shaped bokeh.

Nifty-fifty. I know all about that. That's about my only complaint about that lens. You can end up with some UGLY backgrounds.

tmonatr wrote in post #4022486
I must say, I don't think this the best example of "good" bokeh. Leafless trees seldom result in good bokeh, as can be seen in this example taken with a camera/lens combo reknowned for its great bokeh.

I think it's more of an example of good subject, mediocre bokeh.

If you want to see an example of bad bokeh, look no further than the bottom of this Wikipediaentry on the donut bokeh produced by most mirror lenses.

Hmmm. I'd say that donut bokeh could be pretty distracting, lol.

A note on Bokeh.

Does the blurred background add to the overall quality of the shot, is it pleasing to the eye if so it is GOOD bokeh

Does the blurred background subtract from the overall quality of the shot, is it distracting to the eye causing you to move away from the intended subject matter or artistic look you are going for; then it is BAD bokeh.

Period.

Some lenses tend to have good or bad bokeh, which is part of their design quality, but even the best lens (the 85/1.2 in my opinion) can have bad bokeh in some situations (as exampled above)

I would provide examples, but I am on the road and all on-line examples are unfortunately not appropriate for this site.

My avatar would be a good example shot, but a little bit too small to see the difference.

heres a couple of example of an 85 1.2 wide open and some decent bokeh in my opinion don't you think?

folville wrote in post #4022620
I think it's more of an example of good subject, mediocre bokeh.

If you want to see an example of bad bokeh, look no further than the bottom of this Wikipediaentry on the donut bokeh produced by most mirror lenses.

YIKES! Reminds me of that movie "The Ring".

tmonatr wrote in post #4022486
I must say, I don't think this the best example of "good" bokeh. Leafless trees seldom result in good bokeh, as can be seen in this example taken with a camera/lens combo reknowned for its great bokeh.

Bokeh is the quality of the background blur (and those are not leafless trees, but rather a very tall railroad trestle). As I said it's subjective, your opinion of good bokeh is your opinion and not necessarily mine. As I noted, if you look at the quality of the blur it's very smooth and specular highlights are uniformly round and have no distinct graduaton from center to edge. That's what I look for in bokeh. You're right that it would be more pronounced with a different background, but that wouldn't change the quality of the bokeh.

Mark

steve547 wrote in post #4022271
Can anyone show me the difference between a photo with a good bokeh and one with a bad bokeh. I'm not sure that I know the difference. I guess I'm still trying to get the subject to look good and haven't paid much attention to the background. I apologize if this is a dumb question.

http://www.kenrockwell​.com/tech/bokeh.htm

Very different articles on the topic:

http://www.rickdenney.​com/bokeh_test.htm

http://www.luminous-landscape.com/essays/b​okeh.shtml

http://www.vanwalree.c​om/optics/bokeh.html

This last one is interesting?

http://www.diyphotogra​phy.net/diy_create_you​r_own_bokeh

To me, good bokeh is one that is smooth and without distinct edges, unless it's soft round circle of out of focus lights. Harsher shapes with more distinct edges are usually bad in my opinion.
Here is what I consider a good bokeh. I like a smooth gradation of colors without distinct patterns in the background from a 135mm f2L.