If you're planning a wedding you'll probably find that selecting your photographer is one of the hardest things you'll have to do.

Unlike almost any other service that you'll buy, it's tremendously hard to compare photography products and services. It's even harder to compare photographers.

Many wedding vendors have broadly equivalent services. If you're comparing catering from one supplier and catering from another, chances are that, for the same budget and type of menu, the food will be of similar quality. Likewise the entertainment: as long as you and your guests like the music, one band may be just as much fun to dance to as another. And white table linen from one supplier will probably look pretty much the same as white table linen from another.

It's quite tempting to think that wedding photography is also interchangeable. But, as some couples find out too late, that's not the case at all.

Photography is a deeply personal activity. It may look easy but strangely it's not. The thing about photography is that it's both an intensely technical and intensely creative process. The photographer has to decide what they want the image to say; how to frame it; how to light it; where to pull focus; when to release the shutter. The slightest variation in any of these things will produce a very different image. No two people will ever visualise a potential moment in the same way, and neither of them will ever take the same photograph.

There are two vital things you need from a photographer - vision and consistency.

You have to love how your photographer sees because they will be capturing your day and your memories through their eyes. Do you love their portfolio? If not, move on - otherwise you won't love your own wedding photographs either.

You have to trust in their consistency because you need them to produce excellent work for you - just as they did for their past clients. Most weddings include unpredictable weather, bad light, difficult locations, unforeseen problems and over-running timescales. The right photographer takes all this in their stride, relaxed and confident they can get the shot no matter what. And not just one brilliant shot, but hundreds of them, guaranteed - because they can rely on their consistency.

When you're reviewing photographers, ask to see not one wedding in full, but four or five. Any photographer who is truly consistent will love you for it.

Not all products and services are the same. Two packages with 'DVD and Album' may sound equivalent, but they rarely are.

Some photographers get their albums in bulk from a wholesale supplier; others have their albums built to order as a bespoke piece of art. Some albums are finished in white vinyl and polythene; others are bound by hand with museum-grade archival paper and Japanese silk. Some albums are packaged in a cardboard sleeve; others are boxed and presented in a cedar and rosewood case.

With albums, you tend to get what exactly what you pay for. A £30 album will look like it was worth every penny. Fortunately, so will a £1200 album.

There are even more hidden differences if your package includes disks of images. 

Some photographers will give you unedited images straight out of camera; others may have spent over thirty hours of production work to make every image absolutely perfect. Some photographers will bundle every shot taken, all thrown in regardless of quality; others will ensure their disks are thoughtfully put together, carefully edited and sequenced to produce the most perfect story of your day. Some photographers give you "high resolution" images that will only print to 6x4 inches. Other photographers will give you images that will make 16x20 inch prints.

We feel it's worth thinking hard about your wedding photography. Consider what you want from it - not only on the day of the wedding; but, far more importantly, for the rest of your lives together.

Your wedding can only be photographed once, so it makes sense to have it done properly, and done well. We suggest you select your photographer by their visual style; their professionalism and adherence to detail; their connection to you, and your trust in them.

Choose carefully, because you're selecting someone to preserve your memories for a lifetime.