Have these images been "Photoshopped?"


Yes. It is important, however, to define the term.


I do not use Photoshop to surreptitiously deceive and trick the viewer into believing something is real which actually was not. Rather, just the opposite is true — I use the software primarily to more authentically convey what I experienced in the moment of capture. That being said, I strongly believe that no amount of post-capture "fixing" can be exchanged for excellence, both aesthetic and technical, before clicking the camera shutter. I strive to continually improve my photographic skills so I am spending more time behind the camera and less in front of the computer. Still, "digital darkroom" adjustments are consciously anticipated and intentionally made for a variety of reasons — for example, to correct  known deficiencies or inherent limitations and inaccuracies induced by camera detectors and lenses under various conditions, to combine and blend multiple frames, or to utilize and balance all available raw image file data. All images are routinely adjusted, sharpened, and optimized for digital output, as is the customary standard for most comtemporary professional photography. Also, I produce composite images for a variety of reasons, such as to illustrate a concept, to improve understanding, or to blend unavoidable extremes in exposure or depth of field values. That information is disclosed so the viewer is apprised of the multi-source or altered image provenance. I expect no less as a viewer myself.

It is of value to make a distinction between the camera and the human eye/brain as visual recorders, because both detectors are similar in some ways but very different in others. Thus I use the varied tools of digital photography — camera, lenses, lighting, scanned film, CCDs, computers, software — to document my perception of the moment. I view raw output from these photographic tools not as sacrosanct absolutes (because sometimes they are inaccurate) but rather as elements to be arbitrated, developed, and honed into the finished image. This approach is in part a function of my background in the arts. However, because I have lived and photographed in the world of astronomers for many years and produce images for use by the scientific community, I am acutely cognizant of the imperative for precision and accuracy when documenting scientific subjects. I try to blend my personal aesthetic vision with scientific integrity in the creation of my photographs.

Fortunately, newer cameras, CCDs, and optics are yielding sharper images with much less noise in low light and far greater dynamic range. With vastly improved raw image files, I'm spending considerably less time at the computer in post-production and more time imaging in the field.

A note about color:  Books are written about perception and reproduction of color and it is not my intent to address the subject in depth here. In many of my photographs color plays a dominant role, and in some it might be hard to believe the color is "real." However, unusual or distinctive coloring is one of the reasons I select such images (out of tens of thousands shot) for publication, as is the case for many photographers who seek the extraordinary moment so it can be documented, preserved, and shared. Being ready in the right place at the right time with the right equipment does involve some "good luck" but is equally a reflection of years of experience (including countless failures) in planning, reconnoitering, staying up all night, braving the elements, investing in gear, and learning from inevitable and repeated disappointments.

For a more detailed, in-depth discussion of photographic technique and digital ethics, with examples as well as identification of exceptions to the above, please continue reading:

LASER GUIDE STAR: Terrestrial Photography.

This web page discusses creation of two images that illustrate

author Robert Irion's article "Homing in on Black Holes",

featured in the 2008 April Smithsonian Magazine.


The following is an excerpt from the LASER GUIDE STAR document:




Photo Illustrations and Composites:


Anyone with reasonably good image processing skills can potentially “fake” an image by surreptitiously incorporating elements from other photographs shot at different times and / or places, then falsely representing it as “real” or “as it was in the moment”. Aside from fundamental ethical questions, I do not see any challenge in that, nor would I derive satisfaction from it. Of far greater intrinsic reward is mastering the skills to precisely calculate and execute a difficult and unusual photograph, or paying attention to the nuances of nature and being ready to snap the frame when an extraordinary moment presents itself. Sometimes this is spontaneous, but more often than not it requires tremendous investment in equipment, calculation, and execution. And there are so many failures! Even so, this is infinitely more satisfying for me as a photographer. It is also more meaningful to those viewers who appreciate the pictures and value photographic integrity.

In the years I have been producing documentary photographs for a scientific institution (University of California Observatories), it has been important to me and to my community that images be “real”, and not “faked” insofar as an image is accurately represented. Although images 906 and 991 were captured in single exposures, I occasionally produce composite images for a variety of reasons, such as to illustrate a concept, to improve understanding, or to blend unavoidable extremes in exposure values. However, that information is disclosed so the viewer is apprised of the multi-source or altered image provenance. I expect no less as a viewer myself.

An example is a photo-illustration composite of the iodine cell instrumentation used to discover extra-solar planets at Lick Observatory; see image 2162 below. The image Description text outlines the motivation for, and method of creating the photo-illustration.

2162 Iodine Cell Starlight

Astronomers don’t always take themselves seriously, as evidenced by this photo-illustration composite created jointly with UC master spectrograph designer Steven Vogt:

2140 APF Alter Ego


The camera doesn’t lie — or does it?


Sometimes limitations in image capture media and equipment — film, CCD, lens, etc. — distort accuracy of the image to a degree where I believe adjustment is both necessary and justified to return the image closer to “reality”. For example, some types of film render the laser color as green due to the emulsion’s inability to correctly register the sodium yellow laser color. I believe it would be irresponsible to perpetrate images in which the laser is green instead of sodium yellow, and I know my scientific constituency agrees as I have discussed it with leaders in the field. The CCD in my digital camera much more accurately captures the nuanced saffron shades of the laser, to my relief. (Both magazine images were digital capture.) As previously discussed, the laser usually appears more saturated in the digital image than to the naked eye because of longer integration periods with a sensitive CCD — typically a few seconds to an hour or more, as compared to the eye’s 1/10 second.

CCD development for consumer and professional cameras is a fast-moving technology. As sensors with higher signal-to-noise ratios are produced, nighttime exposures using consumer and pro-grade cameras can be shortened (if desired). Eventually, digicams might reproduce what the eye sees in the same integration period, or close to it. This would give the photographer a choice between making a noise-free exposure that more closely resembles what the eye perceives, or a longer integration showing paths of star trails and a saturated laser of which only the camera is capable. At present, I can see more light at night in 1/10 second than my camera can. The reasons for this are fascinating, but beyond the scope of this discussion.




Should I as the photographer intentionally manipulate and alter photographs by desaturating and toning down long-exposure laser images to more closely resemble the muted laser beam as it is perceived by the naked eye? If so, what about exposure values in other areas of the image that are different from what the eye can detect?


Cover Image Perspective Adjustment:


In the interests of maintaining scientific accuracy, the cover image required a post-capture perspective adjustment:

Although the laser extends about 90 kilometers into the atmosphere, its full length cannot be seen. The thin ochre probe seems to disappear into the sky, but in fact extends far beyond. This is due to a variety of reasons that will not be addressed here. (This part of the photograph was cropped on the Smithsonian cover, but it is visible in the master image.) To capture the transition area in the photograph, I needed a lens that would allow the widest possible field of view while retaining sharp detail. In my kit the best choice was a 10.5 mm f/2.8 fisheye. However, I knew in advance that the resulting laser would appear with an unacceptable curvature typical of fisheye lenses, instead of being arrow-straight. Because Laser Guide Star scientists dislike artificially bowed laser beams as much as sickly green ones, a standard Photoshop filter was applied to restore the inaccurate fisheye distortion to that of a rectilinear view. I see this not as employing Photoshop “trickery” but rather as selecting the most sensible, high-precision tools available to achieve optimal, authentic results.

A similar fisheye perspective correction was applied to image “890 Keck LGS Landscape” mentioned above.

Oftentimes fisheye distortion is aesthetically desirable. It can be an unusual, fun, and eye-catching redefinition of our everyday world. The fact that it is visually impossible for humans is part of its attraction, and I enjoy using it for other subjects as-is without subsequently applying a rectilinear perspective filter. Here are two examples:





My background is in fine arts and music. It is my privilege to live among astronomers and to produce images for that community. I wear two hats as a photographer — that of an artist, and that of a documentary recorder / technician. Both are of equal importance to me; my work results from a melding of the disciplines.

Modern tools and techniques are among the means by which I produce and personalize my craft. I do not use a chemical darkroom, but rather a digital one. Adjustments in image balance, tone, and contrast are made not to “fool the eye” but rather to utilize all available image file data as deemed appropriate. Raw image files or scans can sometimes appear overly flat and washed-out without adjustment to use all legitimate data contained therein. There is a tremendous exposure range in CCD-generated image files, although not as broad in scope as that detected by the human eye in certain conditions. When exposure values of a given scene exceed my camera’s capability (but not my eye’s), I might shoot two back-to-back images of the same subject but with different exposure values (providing the subject is immobile). Those images are then “stacked” together with the best exposure extracted from each and “flattened” into a single broad-exposure image, closer to what I saw in the moment. This is a standard technique commonly used in professional imaging to effectively extend dynamic range.

Sometimes adjustments are made to overcome inadequacies in media and capture, for example, unwanted extremes in exposure or distracting flaws such as CCD noise and film grain. On the other hand, there can be aesthetic and journalistic legitimacy in preserving the authentic character and artifacts of capture media and process.

Ultimately, I try to make the image appear as I remember it, without contrivance or false exaggeration. But of greatest importance is to convey the sheer magnificence and emotion that inspired me to take the picture in the first place. The photograph is a vicarious record of my experience and impressions of the moment, as subjective as those might be.

Platitudes can be simplistic, but I often remind myself that there are no mundane subjects — only mundane photographers. This forces me to see the world in new ways.


Double Standard:


This discussion is not without paradox. Sometimes the camera sees that which the photographer cannot, and sometimes the photographer sees what the camera cannot. In viewing and photographing the laser both statements are true. It is my responsibility and prerogative as the artist / technician / photographer to arbitrate and balance these factors in the final image.

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Learn more about LASER GUIDE STAR: Terrestrial Photography.