Bokeh Backgrounds for Macro Images?

[Kevin Childress]

Despite that I am primarily discussing bokeh here, I would appreciate any tips you have for creating more interesting backgrounds for macro images.

For me creating interesting backgrounds for macro is definitely the most difficult aspect of the entire process. As such my backgrounds are typically black, white, or a few other solid colors from using construction paper as a backdrop. Yesterday I was wondering how I might create bokeh for a background so I punched small holes in the construction paper and placed a continuous light behind the paper.

I tried several holes in a group and then only one hole. This isn’t exactly what I was hoping for but there are definitely some interesting patterns that come out of this. I particularly like the pattern in the 3rd, 5th, and 6th images. Part of the trouble I'm having with my setup is that I have to bring the background in very close to the lens to get what I’d really like and that’s not leaving me much room to place a subject. With the backdrop placed too far away from the lens, the bokeh just appears as a solid color again. And judging by the last image, by the time I light the subject, the bokeh effect on the background may practically be erased.

The last image is using all continuous light however (front and back). I may get different results with a flash on the subject, say at 1/250s, and continuous light behind the paper for a couple of seconds. And I suppose I could change the bokeh color with a strip of gel taped to the back of the paper.

Any ideas on this?

https://lh3.googleusercontent.com/-qGsp ... 0bokeh.JPG

EDIT CR The inage was wider than our forum standard of 1024, so I've made the link so folk don't have to scroll the page sideways to read the text.

[Kevin Childress]

Yesterday I posted a question discussing how one might create a bokeh effect with macro backgrounds. Clearly I already had an idea of how I wanted to attempt that by punching holes in background paper and back-lighting the holes, so I refined the approach a bit and here's what I got. I mostly got what I was looking for in the the bokeh itself.

The bokeh appears larger than I hoped for and I found it very hard to control. I knew the holes should be as small as possible, and the holes here are very, very small made from the smallest straight pin I could find. But for my macro setup the secret in the bokeh was in how closely I placed the background paper to the subject. The working distance to the subject is 2cm from the front glass and the background paper is 1.5cm behind the subject. I didn't intentionally take the high-contrast approach with my lighting but the 3.5cm box I was working within made lighting options/angles very limited!

I'd say the most difficult part of this project was determining where exactly to punch the holes since the framing window is so tight behind the subject. The three holes that create the primary bokeh on the left are only ~1.5mm apart. In any case I stuck with it just to determine if macro bokeh was viable or not, and it appears to be.

Nikon D800 ~ NIKKOR Micro 85mm f/3.5 at f/5.0 ~ Reversed NIKKOR 50mm AFS f/1.8 stopped down to approximately f/8 ~ ISO100 ~ Focus stacked from 50 frames at 1/13 second.

[ChrisR]

It's certainly nice to be able to control it. Mine usually more or less just "happen"

It should be possible with a couple of simple lenses (Surplus Shed) and cardboard tube with a slot, to make a zoomable projected pattern. Could be good with a collection of targets or masks.

[bendecamp]

I had an idea years ago to make the Nike logo as the shape of my aperture, so that all of the specular highlights were Nike swooshes.
Happy I never went through with it.