Click on thumbnails to view larger version. This gallery illustrates the joys and frustrations I experience as I try to learn how to take some decent shots. Except for 2 photos (1st and 3rd) I have left the images unaltered to show the difference in the originals. Some photos can be enhanced significantly using e.g. Photoshop, and sometimes you can get away with such manipulation without obvious degradation of image quality. Other times you are not so lucky, and the more correction your photos need, the worse off you are. In general, the flaws in the photos below are of such character that attempts to save them by manipulation would result in undesired artifacts and to my opinion worse looking photos. So even though digital photography makes some significant improvements possible, the original photo is what really matters. The skills of the photographer still makes the key ingredient, but good equipment sure makes the task easier. When I arrived to Alaska (August 2001), I was shooting animals in Denali National Park with a cheap plastic camera with no zoom. Except for the photos of a wolf passing the bus 2 meters away from my camera, the results were miserable. Now equipped with a Canon 300D (Digital Rebel) and several lenses, the situation is different. If the photos are flawed, I'm usually at fault.
The first photo shows an almost full moon shining through a thin layer of high cirrus clouds. The ice crystals in the clouds are shaped such that they can reflect light at certain angles. The best reflection occurs at an angle of 22 degrees, and it is this reflected light we see as a moon halo (or more often as a sun halo around the sun). Now for the flaws: I had counted on a small blob of snow on the branch to block the glare from the moon - looks pretty useless! Also, it can be seen that the field of view covers just a little less than the 44 degrees it takes to include a full halo. At this point I was helpless - the widest I could make it was using the 18mm end of my 18-55mm Canon EF-S zoom lens. As can be seen below, I have now acquired a wider 15mm lens (Sigma fisheye f2.8) that will allow me to capture full halos.
At the other end, this is how much my 'ordinary' lenses allow me to zoom in. This shot is taken at the 500mm end of my Sigma 50-500mm zoom lens. I have cropped off the black edges, so the large version of this photo shows the full resolution of the original. Most other photos are scaled down by a factor of 3 to save space, bandwidth and download time. Some photos are (unfortunately) not all that sharp, so the reduced resolution doesn't matter much. Others, however, are quite sharp and reveal much more detail than the reduced size shows. See the two photos of the cabin below to see an example. Now, when I say 'ordinary' I exclude my telescope which can be attached to the camera as well, providing an extraordinary lens (1016mm).
As noted above, I acquired a wider fisheye lens, and these two photos show the difference between 18mm and 15mm. Fisheyes warp the image to fit more into the frame. With the appropriate software you can de-fish the image, but not without cutting off some of it along the edges. Better, you can get lenses that fit more into the frame without warping - an example is the somewhat more expensive Sigma 14mm f2.8 lens. However, some people like the warped appearance of fisheye images, considering it as a cool effect. To my opinion, the warping can indeed be cool if you use it in a creative manner, but mostly I prefer photos to look natural.
And if you take care, you can make fisheye images look fairly natural too. The warping in this photo is not really noticeable (or at least a lot less than above). The trick is: Straight lines that point toward the center are not bent due to the symmetry of the lens. But a straight line along the edge, such as the road along the bottom in the above picture - that's where you lose. Truth is I didn't think about this at all when I took the photo. I was just goofing around because I had received the lens the same day and was eager to use it, so I ran out hoping to catch some aurora, but there wasn't much to catch.
The two reasons I caughed up the money for the fisheye: It has wider field of view and it's faster. Faster in the sense that it lets in more light so I don't need as long exposure time. That's what the f-number is about - the lower the number, the faster the lens. At 18mm, the Canon EF-S lens can go down to f3.5 whereas the fisheye is f2.8. That makes a significant difference, and especially when it comes to aurora. When the aurora is good, it has structure in it (rays) and can be quite dynamic. The impressive structure you can see with the naked eye is what you'd like the photos to show too, but if you have to expose 10 seconds or more and the aurora is moving, you can forget about it. However, at this time there was hardly any aurora, and I had actually given up and was on my way back inside. Then some aurora started appearing quite suddenly.
But what's up with the supposedly faster lens - the photos look pretty dark. I checked that it was wide open - that is, that it was set to use f2.8. The lens can be set to use higher f-values, which gives an overall sharper image and more depth of field (the image is in focus over a longer range). That's not an issue here though, so the lens should be wide open, and it was. Well, the aurora is kind of dim, I thought, looking at it next to the alomost full moon.
"Now it's beginning to look better! It's moving too, so now is the time to lower the exposure time so I can catch some detail" I thought.
It was 15 seconds before, so I set it down to 8 seconds instead. When I saw this result, I finally realized that something was totally wrong: The ISO settings which control the sensitivity of the sensor. It was set to ISO 100, which is the lowest for the camera (other options are 200, 400, 800 and 1600). Using e.g. ISO 400 instead, I would get a picture just as bright with 1/4 of the exposure time. This doesn't come without a price. The increased sensitivity also applies to the noise, so the image becomes increasingly noisy (grainy). This is a trade you're willing to make when shooting aurora, but during daytime hours you can usually do without it and use ISO 100 to avoid the grainy look. Though I obviously want short exposure time, there's a limit to how much noise I can accept, and using ISO 1600 just isn't worth it in my opinion. ISO 800 gives acceptable photos. The noise is still noticeable, especially at full resolution, but most often the photos are presented at lower resolution as here which helps a lot. I decided to go for ISO 400 though, hoping I could still get bright images and with hardly any visible noise.
That helped! At the time it was hard to tell if it helped enough though. When the image appears on the LCD-screen on the camera, the brightness depends on the angle you're looking at the screen from. Unfortunately the aurora decided to start fading again while I was fumbling around with the settings. Well, of course I have trees blocking much of my view so I couldn't see what was going on to the north.
I'm hoping for a big show to kick in, but the single visible band keeps narrowing and gradually fades away.
Almost desperate to catch the little aurora there's left, I increase the exposure time all the way up to 30 seconds. Well, this is not worth wasting my time on...
...but since I was out there with the equipment anyway, I could just as well take a couple of moonlight shots of the cabin. This is the best of them, and since it is fairly sharp I have put it here in full resolution so you can see all the detail (warning: 687KB).
For comparison, here's a reduced resolution photo taken later. I might have considered it better than the other if it wasn't for the streaks from the moon in the upper left corner. That bright moon means trouble, especially when using a wide angle lens. One sure solution is to block it totally as in the photo above or keep it sufficiently far away from the field of view. Unfortunately that's not an option with both the moon and the aurora high in the sky.
Not much aurora at this time though. A few weak bands were still visible in the direction of town. For some reason I reduced the exposure time to 10 sec. Once more I decided to walk back in and began to pack down the equipment. At this point it is very cold, and if I don't take care, water will condense on camera and lenses when I bring it back in. Did this mistake once before realizing the importance of it. Solution: Things must be packed in airtight plastic bags while outside and should not be taken out before they approach room temperature.
And then things started happening fast! Bright aurora spread across the sky, and I desperately struggled to unpack my stuff again, reluctant to take my eyes off the sky above. Finally, after having decided where to put the tripod and point the camera, I was back in business. This is taken 3 min. and 49 sec. after the photo above. Settings are still ISO 400, f2.8, 10 sec. The thumbnail looks noisy, but the larger version reveals that it's actually thin clouds. Obviously, clouds can be a nuisance, but they can make the photos more interesting as well. I don't know about here, judge yourself. What I do know is that I don't like a heavily overexposed moon causing flares in my photos! The big fuzzy blobs in the corner above the moon are caused by reflections inside the lens.
The aurora is quite active, so I change to ISO 800 and 6 sec. exposure. I still don't catch much structure (discrete rays, sharp borders), but I remember it as if it wasn't highly structured, and the moonlit sky and thin clouds don't help either.
I shoot away, paying no attention to composition, just pointing the camera towards the brightest aurora. Note that there are no moonflares here, at least not in the form of big ugly blobs. I'm not sure if the streaks are referred to as flares as well. They're not wanted either, but with some luck and skill you may be able to remove them with Photoshop. The moon itself sometimes looks great in aurora photos, but not when they are as poorly composed as here.
The aurora starts fading a bit, so I increase the exposure time to 8 seconds and continue...
It keeps fading. I go up to 15 sec.
But now it's overhead and still moving, so I go down to 8 sec. though it's not all that bright.
The good show is over. I go back up to 13 sec. to catch the fading aurora and some big, ugly moon flares too. The first of these two photos is taken 7 minutes and 17 seconds after the first photo with bright aurora. This short event is called a substorm, and under favorable conditions they last longer and may appear several times during a night. But this night you had to be lucky to catch it. Then again, it's not all luck. The probability is highest around 'magnetic midnight' (the time at which the sun is at magnetic north) which is around 1am here. This substorm took place around 1.20am.
Next morning as I bike to work I am stunned as I look at the mountains to the south (the Alaska Range). Ahem, did I say morning? I'd say it's pretty close, but I guess some people don't consider 1:15pm to be in the morning. When the air is arranged in layers, each having different temperature and density, light changes direction by a slight angle when passing from one layer to another. The result is that light from far subjects close to the horizon can arrive to you via different paths, and you see duplicate images of some areas while others are hidden. This is called a mirage, and most often you see it as the sky dipping down in front of distant hills or mountains as in the photo below [which also shows dust on the camera sensor :-(].
This 'morning', however, it distorted the mountains in a way I hadn't seen before. During the winter, the air is arranged in stable layers whenever conditions are quiet (most of the time), but then the sky is usually clear too. That means a poor view of the mountains because the sun is low on the horizon so they appear against a very bright background, and furthermore, the air scatters more sunlight in this direction, causing a strong haze. At this time, however, snow was on it's way, so high clouds covered the valley while the air near the surface was still arranged in layers. I promptly set up my camera on a tripod to catch the remarkable result, taking photos to stitch together for a panorama view. And boy, could this have been great if only I had learned from my mistakes. I did take care to stop down the lens in order to get sharp photos, but what's the use. This is one case where the noise arising from accidentally using ISO 800 can really do some damage! Maybe a few more blunders will teach me...