You often hear that a particular lens produces "funky bokeh". In fact, it just came up on the thread "Torn 24-70L or 24-105Lis" https://www.fredmiranda.com/forum/topic/948508, where I mentioned that I've seen it on my 70-200/4L IS + EF 1.4x Extender. Of course, this doesn't always happen, but it's kind of wierd when it does. Here's an example.
In my experience, you usually get this kind of bokeh when you have busy backgrounds such as the one shown in the photo you posted with the bush's pattern.
Yeah, I get that with my 100-400L when there are bushes. I always figured it's the pattern of the background, not the properties of the lens, but I don't know much about optics.
Some lenses are more prone to "funky" or unpleasant bokeh than others. Some of us are more sensitive to bokeh than others too. I personally sold both my 50 f/1.4 and my 85 f1.8 because I often found the bokeh unpleasant (under certain circumstances). Here is a shot I took with my Rokinon 85mm at f/4 that I think looks funky, bordering on unpleasant. It supports rogie's comment regarding busy back grounds. The Rokinon bokeh is typically very nice.
rogie wrote:
In my experience, you usually get this kind of bokeh when you have busy backgrounds such as the one shown in the photo you posted with the bush's pattern.
Agreed. Sunlit sticks and stems are also a challenge. OTOH, my 70-200/2.8L IS II and 300/4L IS with the same EF 1.4x Extender do not show funky bokeh in the same conditions.
How hot was it that day? May also be a multiplied effect with heat waves and the bushes could easily be holding more heat in this instance. I experienced the same thing on a 100-400 with extender on a very hot humid day shooting across some shallow water to a damp shoreline with foilage.
Karl Witt wrote:
How hot was it that day? May also be a multiplied effect with heat waves and the bushes could easily be holding more heat in this instance.
Nope. It's not atmospheric effects, it's simply the combination of lens optical properties and the geometry of the scene. The photo was taken on a moderately cool and sunny day, on the Big Sur coast road, on 1 Jan 2010. In this situation, the DOF is very shallow. The bushes are close but well beyond the DOF. The 1.4x TC serves to expand, emphasize and perhaps slightly modify the lens' rendering of the small details. It would not have been so funky if the bushes were a meter or so further back.
All of fancy explanations here but frankly I typically also find some of the "mirror lens bokeh effect" with a lot of lenses where I was shooting a static object with a reasonably low shutter speed and there is just a slight breeze pushing on the plants. Obviously DOF plays into it, doesn't really take that much.
My example was taken on a calm day at 1/800 sec, wide open (f/5.6) and ISO 400.
The two most-funky bokeh styles I know of are (i) donut rings from catadioptric (i.e. mirror) lenses, and (ii) ninja star highlights from some AE Contax Carl Zeiss lenses, like the 28/2.8 Distagon and 85/1.4 Planar.
