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ne time or the other, you may feel tempted to take a picture of a building, whether indoors or outdoors. At first, this seems like a rather trivial undertaking -- until you compare your shots with others, possibly entering a contest and scoring surprisingly low. The recipe to get architectural shots right is quite easy -- but per usual you have to know what you're dealing with to get it right.

First of all, architecture is a difficult case because it won't run away. This is great as you have all the time you need to get your shot right, but it's bad as everybody knows you had all the time, which raises the margin substantially. Showing blurred pictures is a no go -- archi shots have to be crisp sharp everywhere. Sharpness needs a lot of depth of field (dof) which requires a small aperture (f:11, f:16 or even f:22, depending on your camera).

Choosing The Lens

Most often you want to use a wide angle lens with architecture to show as much as possible. This helps dof a lot -- but induces two other problems: the wider the lens gets, the more distortion you will usually see. This is, straight lines start to bend looking like a barrel -- and this requires you to set lines straight in some software later. However, lenses which show heavy distortion most often also show what is called chromatic aberration (ChrA).

Framing The Shot

Once you're ready to get that archi shot, lets get the best from what you've got.
At first, get a great spot where you can put the camera. As wide angle allows for dramatic changes of the picture within only a few steps, you may want to look for the proper spot for a while. Mind you: the building won't run away, giving you plenty of time to find to most fascinating view possible. Don't be shy to go to extremes -- extremely low, extremely high, extremely symmetric, extremely asymmetric -- you got it.

Dropping Lines

There lurks another problem however: once you set up your view, you'll notice that lines start to drop backwards if you point the camera upwards. This phenomenon is thus called 'dropping lines' and with regular cameras, you can do little about this. "Real" photographers will use large format cameras where they can tilt the lens plane in respect to the film plane -- but the usual cameras for consumers have a fixed film and lens plane. Except… except you've got a DSLR where you can mount a so called shift/tilt lens. Nikon offers a 24mm lens, and Novoflex, a German maker (http://www.novoflex.com), offers several adapters for tilting lenses on DSLRs. If you're doing lots of archi shots, this is a must have anyway. For the occasional shooter, software will help to get rid of dropping lines (at the cost of resolution, however).

Steady Your Cam

Once you've found the perfect view, put your cam steady. The most obvious choice is a tripod of course. Sometimes a Magic Arm comes handy, or even a Bean Bag -- but don't try to shoot architecture hand held, that's the recipe for blurred pictures, no matter how firm you think you can hold your camera. A tripod is not only a perfectly steady stand for your cam, it is also the only means to get your camera perfectly positioned. Leveling the cam is a must, and this is easily done with a good tripod…

No Internal Flash

Now it's time to disable the internal flash of your cam. We're going to deal with rather long exposure times and rather huge dimensions and this renders any internal flash obsolete. So by all means, disable it to prevent from ruined shots because it fired at the wrong time.

Setting Aperture

Set the shot up properly: architecture is slow moving with a need of sharpness, which calls for a small aperture. Well, as easy at it may sound at first, things get tricky with modern digital cameras. The smaller the sensor and the higher the resolution (# of pixels), the more problems arise with diffraction blur. As a guideline, you should avoid the smallest aperture in any case, no matter what lens/camera you got. The recommended aperture for best sharpness for a lot of lenses can be found using Google. If you don't get any results, try with an aperture in the middle of the available range. F.e. if your lens range is f:2.8 to f:22, the middle of that range is:
2.8 4 5.6 8 11 16 22
f:8

Setting The Distance

Hence the aperture of choice will be f:8 or f:11 for maximum depth of field and sharpness.
Because you'll use a middle to small aperture and a wide angle lens, we can expect the dof being big enough to cover all of the shot. However, you may want to set the distance to the 'hyperfocal distance'. This is a special distance which varies with focal length and aperture where everything will be reasonably sharp in the frame. With a 20 mm lens (35 mm equivalent) at f:11, the hyperfocal distance is about 93 cm. Set your lens to that distance and everything will be in focus. However, this is only of little importance if you use a wide angle lens at f:11, but if you need in-depth information you may google for 'hyperfocal distance'.

Setting Shutter Speed

Next you will have to set the shutter speed. As the cam sits steady and the building doesn't move, you should expose for the lights (as always shooting digital to avoid blown out highlights (boh)) and set the shutter accordingly. Most places are lit for 1/60 at f:4 in my experience -- using f:11 you'll end up with a shutter speed of 1/8 second -- impossible to hand hold the cam steady at this speed.
At 1/8th, moving objects will substantially blur. This may or may not look good and it's your decision how to deal with the problem: either accepting that blur as an inevitable fact, or lowering the shutter speed even more to get rid of moving objects altogether: slowing the shutter speed to f.e. one second, walking people will simply disappear from your picture. But we're stuck to f:11 @ 1/8 to get best sharpness -- how can we get a longer exposure time without sacrificing sharpness?

Addition

With the advent of Photoshop CS5, you can take several pictures of the same scene and have Photoshop remove 'variable' parts in the picture.

Neutral Filters

The answer is 'neutral density filters' (ND) -- ND filters are just gray tinted glass which doesn't affect color at all (hence neutral density) and they come in various densities. As we want to go for 1 second of shutter time we need (1/8 -> 1/4 -> 1/2 -> 1) 4 steps of darkening -- usually you want to buy a ND filter with an attenuation factor of 64, which is 6 stops, and we'll end up with a shutter speed of 4 seconds at f:11. This will get rid of most any people in your shot, as long as the crowd isn't too big. Single walking people will simply blend into the background and disappear from the final photo -- exactly what we're asking for. Crowded places need even longer shutter times, which in turn require an even denser ND filter and a stop watch to control shutter times in the 'Bulb' mode of your camera.

Polarizing Filters

While we're at it, you may also use a polarizing filter together with any ND filters to get rid of unwanted reflections on windows and to darken the sky some on hazy days. Polarizers are the best way to get good looking architectural shots, so by all means, get some. As polarizing filters usually cost 1 to 2 steps, it's a 'poor man's ND filter' as well.

Waiting For The Proper Moment

Now it would be about time to push the trigger -- but wait for a second. Check if any people are around and if so, if there's a chance most of them will leave the area around the camera soon. If so, wait shooting -- your cam will wait for your command happily. When it's time to trigger, you should either use a remote control or the self timer to avoid unwanted shaking. This is especially critical with shutter speeds between 1/50 and 1/2 second, but it should become a second habit to you to no touch the camera once it's set up.

Summary

For great architectural shots you need:

• a camera , preferably a DSLR
• a wide angle lens, preferably high quality and shift/tilt type
• a tripod
• a polarizing filter
• optionally a neutral density filter
• optionally a remote control
• optionally a stop watch

Postproduction

Once you've taken the picture (which is often referred to as 'the fact'), you can take some measures in post production (a.k.a. 'after the fact') to get the most out of your shot. I'm not doing a software tutorial here, but the usual rules apply: get the curves right, straighten the verticals, level the picture if there's a recognizable horizon (i.e. big water surfaces), and get rid of dropping lines as necessary.
For starters, read the awesome tutorial from Raymond Shay