polarizer

Filters part 2: Polariser and neutral density by Neil Alexander

Sunset from Over Owler Tor, High Peaks using neutral density filters by Neil Alexander

 Following on from last week's post on UV filters, this week I'm going to delve into the other filters that I use.

I have a bag of filters that's pretty much permanently attached to whichever camera bag I'm using at the time. In it I've a couple of different sized circular polarisers (though I don't remember which particular brand I'm on at the moment as I seem to go through these things like they're ten a penny), a Singh- Ray Variable Neutral Density Filter, a B+W 77mm #110 Solid Neutral Density Filter and assorted LEE Filters 4x6" Graduated NDs.

Polarisers are extremely useful for cutting down on glare and reflections, and adding some saturation to skies or foliage. This site provides quite a good example of the effects of a polariser with an article title "Demonstration of what can be done using a polarizer". You'll see as you mouse on and off the image that the foreground grass shows more colour, the sea less reflection, and the sky has more definition. For any respecting photographer, a polariser is essential. The effects of a polariser, particularly the reflection reduction are extremely difficult to re-create after the fact in Photoshop. Not impossible, but painstakingly time consuming, and for the sake of a few seconds experimentation at the time, and the price of a case of a good red it's a no-brainer.

I also use the two circular neutral density filters quite a lot, though obviously not together! I find the Singh-Ray variable ND filter very useful for adding just a little adjustable density to cut out enough ambient light just to slow my shutter a stop or two, though I do often find that it throws a rather bluey colourcast when dialed all the way in. This would be when I use the B+W 110. It's great fun to use and artistically opens up a lot of options. The downside is that once it's on, you can't see diddley through the viewfinder so focus and composition have to be set up before screwing on the filter. Then it's some calculated guess work to get a ball park shutter speed.

Khounagsi waterfall, Laos by Neil Alexander

Finally, graduated neutral density filters are exactly that. The graduation can be either hard or soft. I would use a hard one, if there was clear separation between the dark and light zones in my scene; an ocean horizon for example. Or I'd use a soft if there were elements from my foreground that extended into the lighter zone; buildings or trees spring to mind.

I've written a couple of posts previously on using neutral density filters so to save going over old ground, there's "The key to long exposures", "Silky water shots - it's not that hard" and "Variable neutral density filters".

You can also get reverse grads, gold and blue polarisers, infra-red filters.... the list is almost endless, but the only one of those that I've ever really had my eye on is a Gold 'n' Blue polariser simply because the effects it can create can be stunning.

Finally, in case you missed it, on Friday I posted April's desktop wallpaper for you to download and use complete with a handy little calendar - Get them out here.

Ultra-violet or UV filters. Why I feel they're uneccessary. by Neil Alexander

The Gherkin - Neil_Alexander

 Last week I was party to a rather heated exchange over on the Digital Photography School titled "Lens Filters: To Use or Not To Use? Your 2 cents, if you please!" here. So I thought that for today's blog post I would relate what I do, and my opinion on some of the points raised.

Some of you are probably thinking "What do I even need filters for when I'm using a digital camera?". Well there's several reasons, and several different kinds of filters. Gone are the days of using red, yellow and blue filters for black and white film, but the likes of polarisers and neutral density filters are still very relevant. So, let's start with the basics. The first and probably most used filter is a UV, or Ultra-violet filter. Whether these are actually of any use or not is an oft-debated point. Creatively they serve little or no purpose. In the right circumstances they may cut out a little superfluous UV and possibly prevent some lens flare (and can be very useful in hazy situations in high altitudes), but most people who do use them, pop them on simply to protect the front element of their lens. In the grand scheme of things, I feel this to be unnecessary for the following reasons:

  • Why put a piece of cheap glass on the front of a lens that could have cost several thousand pounds, potentially causing problems with the resultant image? The front element of any lens is generally the cheapest part to repair, and if being as careful as possible isn't enough (I grant you that accidents do happen), then this is what I have insurance for.
  • To protect the end of the lens, I'll use a lens hood. Lenses come with these for a reason and should not be kept reversed on the lens! Here's a prime example on the right. Lens protection is essentially what a hood is designed for, that and trying to negate any unwanted lens-flare. I use lens hoods all the time. In fact I think I only have one lens that I don't use with a lens hood and that's only because I've lost it.

The best lens hood I've ever purchased is this Mamiya rubber lens hood

Mamiya Lens Hood for All Lenses 127mm to 250mm (with 77mm Filter Size) for RB67 and RZ67 - Squashes almost flat for easy transportation

It's made from very sturdy rubber so provides extra protection and squashes up quite flat to save room in my bag, unlike the larger manufacturers' plastic hoods.

Nikon HB-29 Lens Hood (Bayonet) for 70-200mm f/2.8 G-AFS Lens (Replacement)

The long and the short of it is that as with everything in this game - it's all a matter of choice. There's no right and wrong. Just do what you feel comfortable with. However, if you are going to use a UV filter, DON'T buy the cheapest one you can find. Spend a few extra bob and get a decent one, please!

As always, I'd love to hear from you. If you've any comments, feel free to post in the comments below or drop me an email. Next week I'll post more on polarisers and neutral density filters. Watch this space.

Finally, before I sign off I thought I'd share a few frames I made in Manchester last week when the Queen and Prince Philip came to Manchester as part of her Diamond Jubilee Celebrations. Pop over to the Demotix wire service site here