What’s inside?

I banged my knee a few weeks ago and it just didn’t get back to normal so my wife took me to the doctor to figure out what to do.  As part of the exam they made X-rays of the joint to find out if something was loose.  It got me to thinking about how we create photographs.

As much as we talk about using light to create our images the process is actually indirect.  We capture the reflection of light off our subjects, not the light directly.  It’s only on rare occasions like fireworks, sunsets or nighttime shots of city lights that we rely on the direct capture of light as a subject.  A direct photograph of light usually is just a blob of white with no detail – what’s the interest in that?

But X-rays by their nature make images by the direct capture of light.  Sure, it’s the dark areas that are of interest to us, but these are shadows blocking the light from hitting the film (or sensor mostly now) so in a sense the image is truly created by direct capture of light.

This is useful because the energy of X-rays (a form of light we can’t see) allow them to penetrate objects we have a hard time seeing the inside of and that helps doctors, engineers and scientists view elements without taking the subject apart.  The light we use for photography isn’t energetic enough to penetrate most of our subjects; as a result we usually don’t wonder what’s inside of them.  Still, even though the frequency of visible light isn’t energetic enough to penetrate that doesn’t mean we can’t use it to display the inside of subjects.  Crank up the intensity of the light and shine it through a thin enough subject, and it will reveal what’s inside.

For fun I set up my most powerful flash, put my macro lens on the camera and set up a rig where I could shine the flash’s light through some subjects.  None of these revealed elements are invisible to us; it’s just most people don’t hold them up to a bright enough light to see some of their internal elements.  My subjects were just household items but now I’m keeping my eye open for other, more novel subjects for visible “X-rays.”  Got any ideas of where to look?

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On camera flash is good for something

Don’t you just hate the look of images made using that on-camera flash?  The flat look of people’s faces or the harsh shadows on the wall behind subjects?  You start wondering why the manufacturers even put that thing on their cameras.  So much more control when  you can get the flash off the camera and put the light where you want it.

But, sometimes it’s all you’ve got and it does work in certain situations.

Take this image for example:

It’s just a redbud tree starting to bloom in the woods.  I composed it to give the color contrast of the red against the last of winter’s grey as well as the curve of the limb across the image.  The thin spiderwebs were a plus – didn’t really notice them until looking at the image on my computer!

Even though I used a large aperture size to reduce the depth of field so the sharp-focused buds would stand out against the blurred background, the difference isn’t as dramatic as I wanted.  What would really be nice is for the background to be blurred and darker while the limb and buds are brighter.  But how to do that out in the woods?

Wait, what did I learn in school?  Flash for subject, aperture for ambient light?  Gosh, if I only had a flash….   You get the idea.

That blinding insight on the obvious resulted in this image.

I closed the aperture down a stop or two to reduce the amount of ambient light, and thus darken the background, while opening the shutter speed a stop and firing the on-camera flash (set to -0.3EV).  The limb is so far in front of the background there’s no shadow cast by the flash and the background is so far away the flash has little reach to illuminate it much.  The limb is just slightly darker than in the previous image so a little more time in the field adjusting flash ratios would have helped (hard to see that detail on the back of the camera).

Now the image has more of the drama I wanted.  The red buds hold your attention by being in focus and the brightest objects in the image, the curve stands out more to show off its gracefulness and the background provides a sense of place without distracting from the subject.

All as a result of my on-camera flash.  Guess those manufacturers are a pretty smart bunch after all.

 

[Editor’s note:  I do actually know what I’m talking about, just can’t write it down correctly.  You set the aperture for depth of field and amount of flash on the subject, then the shutter speed for the amount of ambient light.  Faster shutter means less ambient light, slower shutter means more.  Total flash amount is controlled by dialing up or down on the flash power.]

Light show

I finally got around to some tabletop photography today, trying to improve my eye for what I call “item” photography.  Doing this helps me visualize what I want from a subject and then create some drama around that.  It’s not something I feel I’m very good at yet; right now takes far too much time to get organized and the results still aren’t satisfactory.  But, practice is how you get to the big leagues, right?

After playing around with some flowers I started experimenting on some glass objects that have internal elements – paperweights and such.  I wanted to see if I could illuminate the interior elements without getting glare off the outside of the glass, always a challenge with curved glass objects.  We practiced this in photo school but I never really felt I understood how to achieve it accurately.  And I wasn’t sure I could do it with the lighting equipment I have on hand.  Still, the flowers didn’t seem to be working for me and I knew the glass would be dramatic if done right.

I started with something pretty basic – clear glass around an interior design.  To eliminate the glare I found all I needed was a narrow slit of light off the flash, which I got by blocking the flash with a piece of black foamboard.

My first lesson from this is make sure the glass surface is perfect – little scratches or dings will show up as the light shines from inside out.  I can take most of these out in Photoshop but it’s better to start with clean materials.

This is direct side lighting – the heart is lying on a piece of black velvet and the flash is right at tabletop level with the black foamboard blocking all but a 1/2″ slit pointing at the heart.

I really liked the look of this.  The next piece sits up more vertical so I wanted to get the light coming from the bottom instead of the side.  Using a large round bowl that is tall enough to put my flash into and point upward I put a piece of black foamboard I’d cut a hole in on top and put the subject over the hole.  I hung another piece of black foamboard up to serve as a backdrop since I would be shooting sideways instead of downward.  All I wanted to show in the final image was the glass piece so I set my aperture where all the black background would have little or no detail.

I have no idea how glassblowers get these little elements inside the glass but they really work out well when lit up.  In addition to the flash under the subject I placed another flash to the right and turned it down to a low power just to give some definition to the edges of the larger fish.  It spilled over a little onto the backdrop (that brighter area up and to the left of the subject) but I found that helped give some dimension to the composition.

The up-from-below lighting was so dramatic I decided to photograph a subject directly from above, looking right down into the light.  I have a glass paperweight that is almost full of internal elements so I put it over the hole in the foamboard and set my camera directly above.  For this I turned the flash in the bowl up almost to 100% in order to get the brightness I wanted in the paperweight.

Not quite the Eye of Sauron but pretty haunting.  Looks like a red whirlpool or an image from one of those scopes they put down your arteries.

Well, with an image like this you can’t pass up some Photoshop opportunities.  So, a la Warhol, I made this.

Even though the dramatic flower photography didn’t turn out they way I wanted I’ve at least learned a little more about photographing glass subjects.  Light and glass always go together well!

Fishing by strobe

I’ve wanted to continue experimenting with using strobes for outdoor photographs, especially of people in some activity.  One of my photography colleagues volunteered to go out with me as long as the photography was about fishing.  Since he habits a lake near me we met there last week for some tests.

Of course the day we picked was the rainy one out of all the nice weather that week but he says fishing in the rain is not an issue and my camera and lens is pretty weathersealed so it was just a matter of keeping the strobe dry.  Too much wind for more than one strobe, though, and that one securely handheld so my lighting angles were limited by how far I could get from the camera using the remote shutter release.

With the generally dark mood of the day the challenge was to light my subject so that is looked somewhat “natural” and not like he was cut and pasted into the picture.  I found adjusting the aperture and the strobe power gave me the control I wanted of the scene.  A little Photoshop work to increase the contrast and I got this image.  Luckily for us, too, since that line of dark clouds in the background drenched us just as we’d packed up and started walking back to our cars.

19mm, ISO100, 1/100 sec., f/4


And since I had these images that didn’t look all that “natural” because of the lighting I thought it would be fun to play with the high-contrast HDR look I’ve seen several photographers use.  Using a single image in Photomatix Pro tonemapping application I was able to use the extreme contrast between the dark background and lighted subject to my advantage.  Increasing the saturation in the grass and adjusting the lighting on that feature seemed to balance the brightly lit subject, especially as the image background faded into darker tones.

14mm, ISO100, 1/200 sec., f/11