Gear gotchas

Once you've spent a bit of time with any camera system, it's easy to get to know its little idiosyncracies. I've shot Nikon since 1989, so I've got used to the button-and-dial interface and, on the whole, I like it a lot. There are a few niggles that crop up from time to time, like the tendency for the autofocus switch to get knocked out of position once in a while (though the D300 does seem to be a bit better in this regard than earlier Nikons - finally!) or the irritating quirk of the D300 and D200 battery to go on strike occasionally. But, for the most part, familiarity breeds contentment.

The trouble is, no matter how much experience you have (or how much you research a new purchase), there's always the unforeseen gotcha that can catch you out. Take, for example, my new 14-24mm f/2.8. I'd been dithering about whether or not to buy this lens for a while... and recently I decided that the only way to make a decision, one way or the other, was to go ahead and give it a try. Compared to my trusty 12-24mm f/4, which it replaces, the differences seemed obvious:

I like:

- the wider aperture. The new lens is useably sharp right up to wide open, giving me up to 2 stops extra leeway for low light or restricting depth of field
- the quality. Can you say sharp? Whilst the 12-24 is no slouch, the 14-24 is bitingly crisp

I don't like:

- the weight. No two ways about it, there's a lot of glass in the new lens - and I can feel the difference carrying it about
- the size. It's long and wide, too, taking up more space in my bag

A couple of months of use out in the real world has just confirmed these initial impressions. But it's also thrown up a completely unexpected one out of the blue. The huge front element - nearly 100mm, or 4 inches, in diameter - is particularly prone to getting mud or water splashes on it.

It doesn't stay this clean for long when the spray's flying...

Sound obvious? Well, I'm used to getting in close to the action with a wide lens, but the smallish front element of the 12-24mm didn't seem to need too much in the way of regular cleaning. My 14-24mm, on the other hand, has needed a careful and thorough clean after almost every shoot - and sometimes after every shot, when there's been a fair bit of water thrown about.

The reason, when I stop and think about it, is fairly obvious. There must be somewhere between 4 and 8 times the surface area of glass (I'm guesstimating) on the front of the 14-24mm, compared with the far more discrete 12-24mm - a factor both of its wider aperture and the fact that it covers a full 35mm frame. Given a certain density of water or mud droplets in the air, that translates to between 4 and 8 times the number of resulting splashes landing on the glass surface.

It makes the sensibly sealed-against-water-ingress mount look a bit redundant, since if there's enough water about to make the lens/camera interface vulnerable the front element will long since have been completely covered in water droplets. Worse, zooming from 14mm to 24mm pulls water out of the serrations in the built-in hood, where it tends to settle, into the lens' innards. I know, because I've been there.

I tend to subscribe to the view that less cleaning, in the long run, is better than more. Paranoid lens polishing is far more likely to result in long-term damage (in the form of scratches and hazing) than any noticeable increase in image quality. Having said that, ultra-wide lenses are particularly prone to showing blobs of water or dust on the front element in the image. There's a compromise to be struck, but so far the 14-24mm is forcing me to clean more often than I'd like.

Whether this is largely because I've been shooting in wet and muddy conditions a fair bit lately remains to be seen. But stockpiling supplies of lens cleaning fluid and PecPads certainly wasn't what I had in mind when I bought it. The jury's still out on this lens.

Comments

[Roo]

I bought one the other week too, my local shop ahd it for a very good price and my current widest was 20mm so I went for it. So far it's been perfect, not a single complaint about image quality or focussing. The size/weight doesn't bother me too much, it's just part of the package. I was tempted by the 12-24 and 17-35, in the end I thought I'd just go for the best, I usually regret it if I don't!

I've yet to touch the front element, when I start noticing a decrease in image quality I'll give it a clean.

[Seb Rogers]

Hey Roo,

If you haven't had to clean it yet you're obviously not getting in close enough ;-)

[Tom Carter]

I'm not even worried about water and mud. I'm worried about scratching the hell out of it. I'm a travel and street photog, and am worried sick about this. I don't know what Nikon was thinking not allowing filters.