Actually, it can be headlights as well if that’s more your cup of tea. I prefer tail lights because they have a nicer color and headlights tend to be a bit too bright for that perfect exposure. A friend just asked about the trick of the trade on msn and I thought I’d whip up a quick post about it.
Long exposure and light trails photograpy is really simple and very gratifying, as you get spectacular results pretty much instantly. But to obtain a nice balance between lights and environmental details takes a bit of experimenting.
First of all, it doesn’t do to take a shot in the dark. Pitch black sky and black concrete don’t reflect any lights and will make the photo look dull. You really want detail and a certain amount of light pretty much everywhere in the frame. Therefore, the best time to take these photos, as in any nighttime photography, is the blue hour, that magical little window of time after sunset when the sky is a rich deep blueish purple. This light will also balance the frame so there will be no overly dark or bright spots, which makes a correct exposure much, much easier.
Of course you can break this rule, like I have done many times. On a foggy night, the gazillions of tiny mist drops in the air will spread and reflect the light and give your photos a dreamlike appearance. Or you can venture out on a rainy evening and catch the gorgeous reflections of car lights on the wet asphalt.
When you have found a suitable spot for your photo, a nice street with nice surroundings and a safe place to set up your tripod, you can start thinking about the delicate issue of shutter speed. Some good rules of thumb:
- The more cars drive past during the exposure, the more lights, the more powerful light trail in the photo. On a small street or road, even a single car can produce a good light trail, but I usually jump for joy when I see two or more drive past in a convoy.
- The car(s) should pass through your frame from front to end during the exposure, so the optimal shutter speed would be the amount of time it takes for a car to drive along the part of the road that you are photographing. If the car drives too fast, it won’t have time to leave a significant trail. If it drives too slow, it won’t have time to pass throught the frame, so you’ll end up with a line that ends abruptly half way - not pretty. So have a look at the average speed of the passing cars, then adjust your shutter speed so that a car will have time to cross your frame.
- I always underexpose these photos by at least 1EV, to bring out contrast in the photo. Also take in consideration that a passing car will light up the image, so make sure you count that in when taking a test shot of the empty street to set the exposure values. ISO speed and aperture may have to be tweaked to obtain the crucial shutter speed, but optimally ISO100-200 and aperture f8-f13 yield the best results.
- If you have a polarizer filter, use it to block out disturbing reflections, for example when the car passes under a streetlight that makes its roof shimmer. A filter also makes it easier to adjust the shutter speed to the desired amount.
I’d love to see your light trail photos, so if you have any to showcase, leave the link in a comment here or on my Flickr page. Good luck!

I’m spending my summer holidays in Skåne (the southernmost part of Sweden) and using my days to explore the prettiest landscape photo sites in the area. One of these is Hallamölla Falls, boasting the tallest waterfall in Skåne (several smaller falls with a total height of 21 meters). It is not the Iguazu, but has some photo op potential all the same.

I arrived pretty late in the afternoon, not wanting the sunlight to shine though the foliage and ruin the shot by throwing the lights off balance. By the time I arrived at the waterfalls, the sun had already set behind the tallest of the trees, giving me the shadow I was looking for.

To begin with, I took some standard shots with the falls in the background, but I wasn’t all that happy with the result. I wanted to get close to the falling water! But it was a tricky challenge, as the falls could only be reached from the water surface, there being no path on the shore. I had to make a choice. Either stick with the bland shots from afar, or remove my shoes and wade in to approach the falls. This was a difficult decision, seeing as I am mortally afraid of walking on rocks, steep places, slippery surfaces, generally anything that is not asphalt or a comfortable, wide walking path. Add the risk of falling into ice cold water and risk losing my entire equipment, and you’ll see why I hesitated.  But the pull of the falls was too great. I pulled off my sneakers and socks and placed them on a nearby rock and hoped to see them again one day, then rolled up my jeans, strapped my backpack across my midriff and took the step into the unknown.

There were a fair amount of large rocks to step on, but I had to take a few steps into the water. In the end I preferred wading in stead of balancing on the dry rocks - the water was not altogether unpleasant and the small pebbles at the bottom felt more secure than the large, mossy, slippery rocks above the surface. All in all I spent a good fifteen minutes - well, more stumbling than wading - before reaching my preferred point of view. I did not dare move too fast: I could not risk losing my balance and toppling backwards, my camera stuff being tucked away safely in my large Lowepro backpack. Fortunately I could make use of my tripod as a walking stick.

Once there a single shot was all I needed. Using my Canon EF 28/1.8 lens and an NDx1000 filter with a shutter speed of two minutes, I got a dreamy, otherworldly look of the falls and the small pond in front of them. As in most photos, preparations took a great deal longer than taking the actual photo.

Afterwards I found myself sitting on one of the large rocks, peacefully dangling my feet almost knee deep into the cool water, feeling the strong current from the falls whirling around my toes. It was an immense feeling of accomplishment, having conquered the dangerous depths of a one-foot deep creek, battling the unnamed monsters dwelling under the surface, and returning to tell the tale - with a pretty decent photo to boot! It was a small step for mankind, but a giant leap for a clumsy chick :) It felt great to face my fears and realize that walking on some rocks isn’t, after all, the end of the world.

I love watching the cargo ships floating by on the Danube river and for a long time I’d been plotting a way to capture these huge, rusty monsters. I got my chance on a rainy morning.

Preparations
I was fortunate enough to spot the ship approaching from afar, so I hadample time to precisely plan my shot. The place for the photo was fixed: standing at the foot of a bridge, I had little scope to move around. I only had my 50/1.8 lens with me, so I had to compose the image carefully - no possibility to zoom in or out. I had to make the most of the situation.

I wanted to put the ship in the lower third and dedicate the lower part of the image to its reflection, as the overcast weather ensured lovely saturated colors and great contrast, the ideal conditions for a nice reflection. The bridge pillars and the structure of the bridge gave a good geometric background to the approaching ship. Having found the appropriate spot for my photo, it was time to act.

Exposure
Because of the early morning gloom, I chose ISO400 and once again blessed my 350D for not giving me any noise grief with this setting. Another important parameter was the depth of field. I wanted a good sharp image of ship and bridge alike, so I chose a small aperture opening, f9.  Thanks to the high ISO speed, I could still use a shutter speed I could handle without motion blur, 1/200.

(I always shoot in full manual mode, as I feel this gives me the most flexibility to quickly and easily modify my settings. According to the moment, I might need to adjust the ISO, one minute later I might need a slightly different shutter speed and so on. M mode gives me the possibility to instantly doing these adjustments, sometimes half without thinking, as the light or scenery around me changes.)

And finally the moment of truth. The ship pushed throught the bridge pillars and showed its big, rusty, ugly face like some ancient dinosaur peeking out from between petrified trees. It was completely silent and so impressive that for one stopped heartbeat, I forgot abut photography and just stared, mesmerised, at it - but then I remembered what I was there for and took the shot. Thanks to the preparations, my fast camera and a bit of luck, the photo came out like I had imagined and planned. Preparing for the photo took about five minutes - one thousand times as much as the exposure itself.

Post processing
… was a fast business. I shoot RAW, so I could do most of the necessary tweaks in Canon’s own, excellent RAW editing software, Digital Photo Professional, or DPP in short. I slightly increased the contrast and adjusted the white balance to get the warm, yellowish colors I had seen on site. I only opened the file in Photoshop to resize and frame for the web.

One of my most popular photos and one I get most questions about is that of the St. Stephen’s Basilica in Budapest.

It was made with real HDR technique, for which I used 5 bracketed photos. HDR is virtually unavoidable in circumstances where you want strong lights and deep shadows to be equally visible in the picture. This is especially true of building interior photos.
The point of HDR is to increase the bit depth (and thus the dynamic range) of photos with different exposure values into one single file, which is then tone mapped in order to achieve the final result. HDR merging and tone mapping is usually done with designated software, such as Photomatix or Dynamic Photo HDR (I use the latter), but can also be done in Photoshop.
For the Bazilika image I put the camera on a tripod, lens pointing upwards to the huge dome. I always use my camera with full manual settings. Here the exposure values were ISO100 and f/16. I then manually adjusted the shutter speed between 1 and 20 seconds to achive the 5 exposures ranging from -2 to +2 EV.  Taking 5 photos in stead of the usual 3 that the camera’s built-in auto bracketing function will allow will get you smoother, more detailed HDR photos. I sometimes take as many as 9 bracketed shots for a single HDR - a tripod is, of course, necessary.

I shoot in RAW, but I usually convert the photos before loading them into the HDR software.  There the tone mapping process will define the end result - whether it will have the ‘overdone’ look or a more natural appearance is totally up to you. If a natural look is desired, the most important setting is the ‘Light Smoothing’ (Photomatix) and the ‘Dramatic Light Range’ (Dynamic Photo HDR).  Here I went for the natural version. To eliminate the greyish tint often caused by the tone mapping process, I also ran the photo through Photoshop, tweaking the color balance a bit to restore the original colors seen inside the church.

A useful tip for your HDR photos is to run them through the Auto Level function in PS - this has a surprisingly good way of removing your usual tone mapping errors, such as loss of contrast and funny color balance.

Finally, here are three of the 5 original shots used for the final photo and the tone mapped, non-photoshopped result: