ESTABLISHED 2010 - Beyond The Campfire was created to encourage readers to explore the great outdoors and to observe it close up. Get out and take a hike, go fishing or canoeing, or simply stretch out on a blanket under a summer sky...and take your camera along. We'll talk about combining outdoor activities with photography. We'll look at everything from improving your understanding of the basics of photography to more advanced techniques including things like how to see photographically and capturing the light. We'll explore the night sky, location shoots, using off camera speedlights along with nature and landscape. Grab your camera...strap on your hiking boots...and join me. I think you will enjoy the adventure.

Friday, December 22, 2017

The Story Behind the Photograph - The Nebula of Orion: Where Stars are Born

The beauty of photography is its ability to be expressed in so many ways. I have often promoted the idea of what I call Cross Training where as a photographer I want to pursue as many kinds of photography as I can. The reason being, by doing so you will strengthen your overall understanding of the photographic process. One of the most fascinating and challenging forms of photography is Astrophotography. It forces the photographer to look at the exposure process from a different perspective and at the same time offers up a fascinating opportunity to see a part of creation that is virtually invisible to the unaided eye. However, with the camera's ability to accumulate light, even what appears invisible can be captured by using a few relatively simple techniques. Photographing the night sky requires one to not only expand more deeply into the elements of photography, it also requires you to develop a basic understanding of the night sky itself. When both are combined, the results can be spectacular.


As part three of the 'Story Behind the Photograph' we will take a look at one of the most challenging photographs I've ever captured; The Nebula of Orion: Where Stars Are Born

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The winter night sky and the summer night sky offer two differing vantage points for observing the heavens. The summer sky provides a fascinating view toward the center of our Milky Way Galaxy. Bracketed by the constellations of Sagitarius and Scorpius, our view toward the center of the galaxy is filled with bands of dust and gas and billions of stars. With just a simple wide angle lens, a tripod, and a dark sky, you can capture amazing images of our home galaxy as it arches above the southern horizon.


Fast forward to winter and the night sky changes and so does our view. Instead of looking inward toward the center of the galaxy, we are now looking away from the center toward the outer edges where wispy bands of stars orbit and we begin to look toward deep space. The constellations also change, and one of the most prominent is the constellation of Orion, the Hunter.


Orion forms a basic X in the southern winter night sky and consists of a variety of stars including four stars forming the corners, three bright stars forming his belt, and three stars below the belt forming his sword. One of the sword stars is actually a nebula, a place where stars are born, and it is one of the few nebula's of this type visible to the unaided eye appearing as a slight smudge forming the center star of the sword. This nebula when seen close up in all of its glory is one of the most beautiful in all of creation.

It is here dozens of new stars are being created within a gigantic fan of gas and dust consisting mostly of hydrogen , which also accounts for the reddish hue. It is also one of the easiest nebula's to capture using simple photographic equipment. But, to do so requires an understanding of basic celestial mechanics. You see, as the earth spins, the stars appear to move across the sky. This movement can be measured quite precisely and equals so many degrees per minute (I don't recall the exact number). To be able to photograph this relatively dim nebula, you must be able to do three things; use a long telephoto lens to make it large enough to see, use a relatively long exposure to accumulate the dim light, and because of the long exposure and long focal length lens, you must be able to track your camera across the sky at the same rate as the apparent movement created by the spin of the earth.

It sounds more complicated than it really is. Yes, you can purchase expensive camera or telescope tracker devises that work quite well, or, using a bit of ingenuity, you can build your own. The most common home built tracker is called a Barndoor Star Tracker. It is simply two pieces of wood with a hinge at one end and a drive mechanism located at the other end. There are some precise measurements required, but that falls outside the discussion scope of this story, but there are numerous examples available.


The drive mechanism must turn exactly at 1 rpm, or one full revolution per minute. It also requires that it be aligned rather precisely with the north star, actually just to one side of the north star. Once every thing is attached and aligned, and the drive mechanism is activated, this simple devise will quite accurately track deep sky objects for up to several minutes allowing your camera, which rides on top, to take clear and sharp long exposures bringing into view that which is not visible.

And so it was, one March evening in 2014, my Barndoor tracker devise was attached to a sturdy tripod and a small 1 rpm motor was attached to the drive mechanism. With some trial and error, the tracker was aligned with the north star, and using my 500mm lens, I zoomed in on the Orion Nebula. It took several attempts to get the exposure and focus correct and also a few slight tweaks of the north star alignment, but I eventually enjoyed what proved to be an amazing evening of shooting the night sky.

Standing outside on a cold winter evening under a clear sky is almost like viewing Heaven from afar. On this particular evening it seemed as though I could actually see to heaven and back as the night proved to be dark and clear, adorned with silver jewels. Hovering above the southern horizon, Orion the Hunter shimmered in all of his glory, bold and bright, unmistakable by its form, unbelievable in its clarity. It stood like a beacon as though its placement was purposeful and it shined as a visable symbol representing all the other hidden wonders residing just out of visual reach.

The tiny 1 rpm motor was activated and gently hummed as the connecting arm it turned rotated the drive shaft which slowly moved the barndoor tracker allowing it to counter act the rotation of the earth and stars. Using a remote shutter cable, I pressed the shutter release and counted from 1....18, 19, 20. A few seconds later, across the view screen appeared the reddish glow of the Orion Nebula. Using the viewer zoom, I took a closer look and realized my measurements and alignment on this occasion appeared to be dead on right. After a few more shots, I rushed inside to download them.

The image required some slight tweaking in Photoshop, brightness, contrast, color corrections, noise reduction, sharpening, all in small increments to enhance the elements already there...and a final crop to bring the nebula to its final appearance. Being my most vocal critic, I tend to find fault in almost all of my images, but even after close inspection, this capture exceeded every expectation.

Several previous attempts to photograph this same nebula had resulted in frustratingly blurred and imperfect images resulting from improper alignment of the tracker. But, when I took a close look at this one, the surrounding stars appeared as sharp pin points of light and the subtle delicate textures of the red, pink, and blue giant gas cloud floated across the darkness of space in a choreographed dance of color. Embedded within that cloud were the glowing beginnings of new stars having just formed not so long ago in celestial terms.

Orion Nebula - Where Stars are Born
All the hard work, the research, the trials and lots of errors, the endless nights standing in the cold air when the conditions were marginal, had finally paid off. With this single photo, my view of the heavens changed. The Nebula of Orion, where stars are born, became more than just a winter constellation, it became a photographic pathway to the hidden wonders of the heavens.


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