Basic Tips for Photographing Aerogels Accurately

In documenting aerogels, borrowing a few basic photographic techniques will serve you far better than the standard “point and shoot” method.  Because of its nebulous and often transparent appearance, silica aerogel will often confuse the default settings on consumer and professional grade cameras.  Following a few basic guidelines will result in sharper images, with greater surface detail and texture imaged clearly – much better for communicating the quality of the samples you have to others.

Some of the most common problems I have encountered while photographing samples are outlined in the following sections:

• Focusing
• Establishing Scale
• Stability and lighting
• Capturing blueness

Focus on This

The greatest difficulty often experienced when photographing silica or other transparent aerogels will be obtaining correct focus on your sample.   This is caused by a lack of sharp lines around and within monolith.  With no contrast, your camera has nothing to focus on, which often results in the “wild focusing back and forth” that often frustrates our efforts to capture quickly moving objects like pets or children.

In most instances, with your sample placed under strong lighting, this can be overcome simply by depressing the shutter release halfway while aiming the camera at another “reference” object (not pets or children) at approximately the same distance as the camera.

With the shutter release halfway depressed (thus locking the focal distance), re-aim the camera at your sample and push it in entirely.  This will release your shutter without the focus resetting and record your image in correct focus.

A handy technique I often use is to place a sheet of graph paper underneath my sample and focus immediately to the left or  right of the monolith.  This solves both the focus issue and problem of establishing scale mentioned next.

How Big Is It?: Establishing Scale

Often, small samples are photographed without a point of reference, leaving the viewer confused as to the size of the features they are following.  All-white backgrounds may work well for product shots  and Apple advertising, but will make it difficult to accurately communicate the qualities of your samples.

The easiest method for establishing a sense of scale is to add a ruler in the picture, or graph paper as outlined above.  I would recommend against placing printed words around or behind your monolith as type size is easily manipulated and therefore hard to verify after the fact.  Shots in-hand are beautiful but reduce your ability to slow your shutter speed and may to add to blurriness indoors.

Tripods vs. Light

In indoor settings, most cameras will defer to a slow shutter speed setting, meaning the shutter will stay open for an extended period to let enough light in to properly expose the sensor.  The downfall of this is that indoor shots or shots in dark settings (often times a basement or garage laboratory) will result in blurry “drunk-effect” images.  A general rule of thumb is that 1/30 of a second tends to be the longest a handheld shot will remain in focus – anything longer like 1/15 of a second or more is very hard to keep in focus.

Tripods are a good way to deal with your camera’s natural tendency  to slow down in response to dimmer light without blurring out the picture – This is often essential when photographing in a controlled lighting situation (a room without widows or a situation where moving delicate gels is not a good idea).  Adding more light is helpful, but generally avoid overly spotlights nearby as this creates dark shadows and blown out (white) highlights.  The ideal is to raise the light level evenly across the whole scene you are photographing – rather than placing your sample in a moody spotlight – unless you’re trying to make a dramatic effect.

Getting Deep Blue

One of the most difficult tricky things to achieve (and most desirable) when photographing silica aerogel is to photograph the blue of rayleigh scattering through the material.  This subtle effect can be enhanced through a few easy steps.

First, place your monolith against a black background.  Much like the sky (which is backdropped by the inky awesomeness of SPACE), the blue is most evident when there is little or no backlighting to promote Mie scattering (the orange that this produces tends to wash out the blue.

Second, disable any flash your camera has – against a black background, the flash will blow out the color of the monolith, most often returning an image of a white, indistinct blob.

Finally, try to light your sample from the direction the camera is shooting from – this will cause the maximum amount of light to bounce and scatter blue to your camera.  You be getting the “frozen smoke” appearance in no time!