Showing posts with label neutral density. Show all posts
Showing posts with label neutral density. Show all posts

Saturday, 17 October 2015

Through a Filter Darkly


Long exposure photography, where the shutter is left open long enough to blur even slower moving subjects in the frame, has been with us for a long time. In fact in photography's early days the poor sensitivity of photographic plates compared to the film speeds we are used to today made it impossible to do anything but, requiring portrait photographers to put to use braces to hold their sitters heads still less any small motion during the many seconds to minutes the shutter was open blur the image. As film sensitivity improved and it became the norm for photographers to truly be able to freeze an instant in time and long exposure photography became something of a special technique. Often this involved night time exposures such as the familiar images of star trails, where darkness allows the shutter to be left open for hours even with today's more sensitive materials. Sometimes though it would be desirable to leave the shutter open for long periods of time even in full daylight, for example to give a soft gossamer appearance to the flow of water in a fast moving stream. When simply closing the aperture down to its smallest setting isn't enough photographers wanting to achieve this effect have long carried neutral density (ND) filters to cut down the amount of light reaching the lens by perhaps three to four stops which might allow exposures to be stretched out to a full second or more.

It's hard to say when but over the past decade or so a growing number of photographers began to push the envelope of where these long exposure techniques could be applied. By extending exposure times even further, to minutes instead of seconds, motion such as the rolling of waves or the drift of clouds across the sky could transform the entire feel of a scene, achieving a new level of abstraction by viewing the world over a time scale much different from those at which our eyes operate. Suddenly, rather than three or four stops, photographers began seeking out ND filters that reduced light by ten stops. There are now many such filters on the market.

If you have never used a ten stop ND filter, you need to look carefully at a rather bright scene to be able to tell that they are not completely opaque. (It is not safe to look directly at the sun through a 10 stop ND filter however, or any filter not specifically designated as safe for this purpose. This includes looking through the optical viewfinder of a camera with a filter in place. Seriously.) The effect, as you would imagine, can be dramatic, altering the feel of a seaside image as radically as the use of infrared film can transform a photograph of a forest scene.

Having moved beyond a technique a photographer could pull out of their bag of tricks for special occasions, long exposure is now often referred to as a different kind of photography, its own genre. Photographers have built successful careers largely, sometimes almost entirely, through their long exposure work. I wouldn't dare be so presumptuous as to try to list the "most notable" long exposure photographers, but to give you a taste you might want to have a look at the work of Michael Levin,
Keith Aggett, Nathan Wirth or Paul Simon Wheeler.

Do so and you'll probably note the way bodies of water feature strongly in the portfolios of these photographers. While long exposure techniques affect the appearance of anything in the frame that is moving - windblown grass, clouds, humans - somehow it is water and the motion of waves that seem to create the greatest emotional impact, especially when the ethereal mist created by motion and time is contrasted with the solid unmoving presence of a rock, a pier or the wreck of an old ship. I imagine it would be hard to incorporate long exposure photography into your work if you lived out on a prairie.

Situated as I am among the Great Lakes, effectively oceans in terms of their photographic potential, I have favourable geography for long exposure photography easily at hand. It may seem a bit surprising, therefore, that it doesn't constitute a larger portion of my work. I should say first of all that this is in now way because long exposure isn't in line with any personal philosophy or ideal about photography. In my understanding the reason we might find photographs in particular so fascinating in a way that the actual scene photographed may not have hinted at even if we were present when it was taken is that the camera presents us with an image that is familiar and recognizable in a way we can easily relate to, but through an eye that sees the world in a different way than we experience it. We can make creative choices to record in a way that may be a little more or a little less like the way we see the world with our own eyes - motion versus still, colour versus black and white and so on. Often times we find the fascination deepens the more an image differs from the way our eyes see it. Add to this the photographic essence that anchors the image to reality and the fascination deepens. Long exposure photography then is just one more way in which the camera can see the world differently.

I hasten to add it is not an unreal way. If creatures somehow evolved to see the world changing on a time scale of minutes rather than fractions of a second what we see in a long exposure image might be a better representation of how the world really looks to them. To such beings the sort of everyday image we see now made at a shutter speed of 1/60th of a second might be as strikingly unusual as Harold Edgerton's images of a bullet frozen in motion as it emerged from an apple it had been shot through. While we tend to think of the way that we see the world as "objective" and any other way as somehow "unreal", these are accidents of the kind of beings we are. This isn't to say that how we see the world is irrelevant to the way relate to a photograph. I don't imagine an image of a scene made in radio frequencies would have much emotional impact. There needs to be that anchor.

In the end then my choice to stick with the usual sub one second shutter speeds comes down to the particulars of what my muse chooses to whisper in my ear at any given time. I choose to make long exposures sometimes, but not usually in much the same way I shoot colour film sometimes, but not usually. I just have to trust the muse, she's been good to me so far. (What, I can have a female muse if I want to.)

One reason I often don't choose to go with extended exposure time is clouds. If you've been following this blog for any length of time you'll know I love clouds. In fact the very reason I'm writing at this moment rather than being out there with a camera is that there's a beautiful cloudless blue sky outside my window right now - useless. The way clouds render in long exposure images, silken puffs rushing by like freight trains or sometimes extended into aurora like fingers reaching across the skies, can sometimes bring an ethereal sense of its own to an image, but that's not what draws me to the, at least not usually. I'm drawn to clouds for their form, foreboding, the play of light and the sense they give that the sky is a thing. Whatever an extended exposure times may bring to the way it renders clouds, much of the time these other things can be lost.

And so it was that last week I finally found myself at a beach on the shore of Lake Ontario I've been meaning to explore. The weather was terrible, and by terrible I mean just about perfect - blustering winds stirring up waves, dark threatening clouds with the occasional break to let the sun flood through. I walked the length of the beach with the big pack containing my Wista kit then, having shot all 12 sheets I had with me returned to the car and grabbed the smaller pack and did the whole thing again with the Bronica. I honestly hadn't given any thought to doing long exposure on this outing and while I had my 77mm thread size ND filter with me, there were no thread adapters packed anywhere meaning the one and only lens I could use it with was the 50mm Nikkor wide angle for the Bronica. It wasn't until well into the morning, when I came upon a large branch that had washed in from who knows where with what appeared to be a sort of cobbled together ladder I would guess once lead to a tree house still attached that I had any notion of getting it out. Objectively it seemed the clouds were just the sort I usually like to shoot just as they are (or as they appear to me) and the rough surface of the lake with waves that would curl then spread into a frothy blanket as the hit shore were ideal things to incorporate into the photographs I was taking but, you know, the muse.

I have two film backs for the Bronica and on this day one was loaded with HP5+ which is excellent generally and has the speed to allow me to hand hold when the need strikes, the other containing Fuji Acros which, among its other virtues probably the best film ever created when working with exposure times longer than a few seconds. As luck would have it the composition called for the 50mm, the only lens my 10 stop ND filter would fit. To this I added a Cokin graduated grey filter to save me having to burn in the sky later on and a pair of 90 second exposures were made. It seemed prudent to at least rattle off a normal exposure too so after switching backs, removing the ND filter and putting the grad filter back in place I did another shot on HP5+ at, I think, 1/30th.

The long exposure result is up at the top where it stands the best chance of catching the eye of potential readers. It is almost an entirely straight can of the negative though I burned in the lower right corner in Photoshop just a smidge. Now for comparison here is what I got without the ND filter:


For easier comparison here they are side by side. You might want to click to enlarge:


Your evaluation may differ, but even though I'd be happy with the normal exposure if that's all I had taken and your view of the situation may differ, I'll make no bones about the fact that I prefer the long exposure version in this instance. It's true too that I put a good deal more time in Photoshop with the standard version to get it to look as good as I think it could though honestly this is probably due at least in part to some vignetting imparted by the cheap no-name neutral density filter I've been using (even some expensive ND filters are prone to uneven expousre) doing some of the burning-in work for me.

Who is to day if I'll be making this sort of image more in the future. Maybe I'd use it more often if I had something better than a no-name filter. It's an investment I've been considering. (There's never a shortage of things one should consider investing in, is there?) At the very least I'll have to be more careful in future to keep my thread adapters at hand.


Saturday, 11 October 2014

Adventures in Long Exposure

The technique of long exposure photography, purposely using exposure times ranging from several seconds to several minutes or more to create time dependent effects such as giving flowing water a gossamer appearance or creating continuous light trails from the motion of stars or tail-lights, is nothing new. As you may already be aware however over the past several years the popularity of using long exposures in landscape and architectural photography, not just as a special technique reserved for particular kinds of situations, but as a sort of de facto approach that can be applied nearly any time something in the frame is moving, has been growing to become almost a style of photography unto itself. For many well known and highly talented photographers it has become somewhat of a signature look.

An exposure of several minutes I made last year. Lacking the near-opaque neutral density filter often considered requisite for long exposure photography my attempts at long exposures like this were limited to those two narrow time bands each day when the sun was just far enough below the horizon to permit extended exposure times. A bit too dark and exposure times quickly climb from minutes to several hours - far longer than I was willing to wait it out. 

While a deep appreciation for the work of many of these photographers has lead me to incorporate long exposure into my own, I have to confess I'm a little leery about it. The technique seems to be most commonly applied today in a way that is right up my ally photographically speaking, to use the motion of ripples and waves to transform the textured glassy surface of oceans, lakes, firths and so forth into something that appears far less substantial, a mist perhaps. Clouds, meanwhile, often shed all pretense of being stationary when exposures go on for more than just a few seconds. As a result fairly ordinary scenes can take on an air of mystery, a juxtaposition of the familiar and the other-worldly.  Had I ever sat down to write a photographic manifesto the previous sentence would probably feel right at home among its pages, so what's not to love?

A small part of it at least was simply cost. Photographers who regularly use long exposure techniques typically recommend a 10 stop neutral density filter, at least as a start, and maybe a few more 2-4 stop filters to stack on top of that when 10 isn't enough. Considering the advice I find tends to come from photographers for whom long exposure plays a big roll in their work, and who typically are working with larger budgets than a schmoe such as myself, some rather premium brands get mentioned. By far the most commonly cited is the Lee Big Stopper, a square drop-in filter requiring an adapter ring and holder (ideally for each lens) which would easily run me over $200 once all is said and done. Considering that's what I paid for my most prized component of my RB67 system, the 50mm Sekor C lens, it wasn't something I could see ever working its way up to the part of my priority list where things get bought. Fortunately with a bit of digging I was able to find a generic 10 stop filter for under $20. So far it's proven to be perfectly adequate and if long exposure proves to be a more satisfying creative outlet than I've been thinking I can always upgrade.

A more recent photo made through a 10x neutral density filter in order to achieve a 90 second total exposure time. Using Fuji Neopan Acros film eased exposure calculations somewhat a no reciprocity adjustments are required for exposures up to two minutes.

Somehow I'm not seeing it happening though. There are things to be lost as well as gained when this technique is used. I don't always like what it does for the look of clouds for example. There are also times when the surface of the water as it appears when exposures are short enough to freeze its motion is what works best. For an example of this have a look at the first photo in my previous post and note the texture of the water  and how it helps tell the story of churning winds and sunlight. I would be quite a different photo if the shutter were kept open long enough to allow this motion to blur into a sea of marshmallow fluff. Arguably it might still be an interesting photo, it just wouldn't say what I wanted it to in this case.

This might be why, despite my interest in experimenting with long exposures and my belief that it may be the key to getting the right look in some circumstances, I have no ambitions of making it a signature look of my own. When looking through the work of photographers who turn to the technique time and time again I can sometimes get a little numbed by a certain sameness of feel. It leaves me to wonder if for some photographers the heavy neutral density filters are being brought to bear out of habit. I have my own filter to play with now so it remains to be seen how it goes for me. As always I'll keep you posted.