sensitive light: photographing smoke

Tips on Photographing Smoke


Introduction Let me say straight away there is no right way to photograph smoke, it is largely a matter of experimentation to find out what works for you. This article is a description of my own methods, and a few things I have discovered along the way. I hope you find them useful. After ignoring smoke photography for 3 to 4 years I decided it was time to have another bash. In preparation for my latest smoke fest I searched the web for smoke images and smoke tutorials for inspiration and guidance from those taking smoke pictures while I was sitting with my feet up. Not surprisingly I found loads of them. Almost all the tutorials told me how easy it was to take smoke pictures, I spotted a gap in the market. I don't want to contradict anybody and say 'actually it is quite difficult' I just want to go into a little more detail and look at some of the pitfalls that could spoil the end results. Is yet another article on this subject necessary? There has been a ‘how to photograph smoke’ article on sensitivelight.com since 2004 when it was the only article on the subject of coloured smoke photography. So it is not another article it is just the original one brought up to date. There is a lot of brilliant and stunning smoke art out there, but there are probably more out of focus, poorly exposed smoke ‘art’ pictures on the web than there are out of focus poorly exposed pictures of cats. There must be a reason for this and it could be due to the lack of articles about what could be going wrong. Instead of directing this article at making the best smoke art pictures better, it is more to do with raising the standard within the genre as a whole. What I am looking for in my own work is well composed, clearly defined line and shape with smooth transition of smoke density throughout the image. The smoke should be, or at least appear to be, in focus across the image. Exposure should be controlled to the extent that there are no burned out whites or blocked up blacks in the smoke, unless this was the intention; blacks and whites do not take colour very well. Finally I should like to be able to print the image at 30 by 20 inches hang it on the wall and have it bear the scrutiny of those people who study large pictures from 6 inches away, you know the ones. That last part about large image size is probably the most difficult to achieve. Where to shoot The room where smoke art is created has a bearing on how the shooting session will go. For most control of the smoke plume a draught free room is required. For the sake of family life you may have to take into consideration the effect of incense and it’s smoke on the rest of the household. The ash from incense will mark fabric and carpets, probably not permanently but… only you can know the implications of doing something dirty and smelly indoors. Ventilation is important for a number of reasons. After a while smoke will build up in the room you are using as a smoke studio. For your health it is important to be able to regularly clear the air. More importantly as smoke builds up it will scatter light, the background will become less black so you will lose contrast, and in the worst case you will be photographing through a haze which is not good for image sharpness. Smoke rises because it is hotter than the air around it, we know that much, but indoors it can only go so far. A shapeless fog of smoke will build up near the ceiling of the studio, and after a time as more smoke is added the fog will expand downwards until your eyes start to sting and you remember about ventilation. If you are working in a warm room the smoke will dissipate into a fog closer to the source (the smoldering tip of the incense stick) than it would in a cold room. So to some extent smoke pictures are going to look cleaner, crisper and more contrasty if shot in a cold room with a high ceiling than if shot in a warm room with a low ceiling. A room with an external door and windows would probably be best. Let the smoke build up for a while, say 20 minutes, then stop burning and then start flushing the room with clean air, use your judgement. Flushing will often result in lowering the room temperature which is also good. I find that 10 or 20 minutes with a particular configuration of lighting, camera settings, and smoke manipulation is long enough to want to run off to the computer and assess the results. Lighting the smoke Imagine a darkly appointed room with no shiny surfaces to encourage reflection. See it is lit by one small, high, single pane window, facing towards the sun, see the patch of sunlight on the floor. If the air in the room is dusty or smoky you will be able to see the whole ray of light from window to floor. If the air in the room is clean the ray will be invisible and just the patch of light on the floor will catch the sunlight. In the clean air room set a smoke column to pass through the sunbeam and photograph the smoke against the dark walls of the room. With any camera, and no tricks, simple effective smoke pictures can be taken ready for post processing. I have never found the right room, but I know some people have, and it saves an awful lot of messing about. On the down side this setup will only work at a certain time of day, if it is sunny, and not at all at night. Sunlight also has the annoying habit of moving around the room. The alternative that almost all of us are forced into is to light the smoke artificially. To enable the smoke to be seen there needs to be good contrast between the brightly lit smoke and the dark, unlit background. To get the degree of contrast required, in most cases the only option is a flash unit. Unfortunately most if not all ‘on camera’ flash units will not be satisfactory, as the light that falls on the smoke will go on to fall on the background, reducing the contrast between smoke and background. An off camera remote flash unit is the way to go. One unit should be enough to light the scene although two or more units could be arranged to give a more even light across the area where the smoke is expected. The final placement of the lights is part of the trial and error, or experimentation you will need to go through. I have read several accounts where photographers have placed the lights low and angle them slightly upwards into the smoke, I don’t do this I prefer to have the lights roughly level with the subject area. My reason is that as the smoke tends to be denser the closer it is to the source and I would prefer not to concentrate most of the light into the densest areas, instead go for a more even lighting. Flash to subject distance has to be considered, if the lights are too close to the smoke there will be a falloff of light from one side of the subject to the other, experiment. What happens to the light after it hits the smoke is a matter of supreme importance. We don’t want any light to fall on or be reflected onto the background, similarly we don’t want it to be shining on the camera creating flare. A lot can be achieved with some black card, scissors and a roll of sticky tape. Basic lighting setup As I am the proud owner of two studio flash units that is what I use. These two equally powered units are seen here set behind the smoke and at about 30 degrees off the viewing axis. I find that having the lights more behind than to the side of the smoke gives a better sense of depth and transparency in the shot. There is card hanging off the lights to ensure they don’t leak onto the background, and card wrapped around the little vase holding the incense stick to stop reflections. The other items on the table are tea lights to manipulate the flow of smoke, more about these later, and a piece of cooking foil that has been shaped by scrunching it around my little finger, I just pop the foil on top of the incense stick to put it out. Flags to stop lens flare More black card, this time used as flags to stop the light from the flash heads from reaching the lens. I want to stress at this point that studio lights are not necessary, any off camera flash unit will work. Psycho_Babble the administrator of the flickr group Smoke and Mirrors wrote to say 'My crude set-up involves photographing with just an off camera flash and a simple black felt background, in the garage, no less.' We just use what we have available, I think exploiting the garage as a smoke studio is an excellent idea. The background. The nearer to black you can make your background the better. It may not sound all that important now, but when it comes to post processing, manipulating light levels and colour, having a black background is important. Black or scientific black (RGB 0,0,0) is immune to most of the post processing you will do later on, whereas dark grey or any other colour except white is not. Looking back at the picture of the basic lighting setup you can see several ‘blacks’ in the picture. There is the black of the bed linen on the table and on the wall behind the lights, the black of the card hanging off the lights, and in the centre of the wall the true background for photographing is a length of cotton velvet, clearly they are not all the same. Available from fabric shops cotton velvet gives the densest, darkest, least reflective surface I have found to date. A similar product, nylon velvet has a reflective sheen and is not as good as that made of cotton. You may think that I am making too much of this black business, after all you can always pick up a black paintbrush in your image editor and make all the non smoke areas RGB black. In fact I often do this. However, where you want to preserve the natural look of a veil of smoke getting thinner and thinner until it finally disappears altogether, a paintbrush is not going to help if the background wasn’t black to start with. If your background is not quite black there is another route you could take in post processing. Use the black point slider in your raw converter, or the black pointer in the Photoshop levels pallet, and force the not so black into true black. Again though, this is destructive, and that delicate diminishing veil is going to look far less delicate. Sources of smoke Anything small and non toxic that will smoulder without going out is a potential source of smoke. I use incense sticks because they are reasonably clean, reasonably cheap, easy to manage, burn for a long time, and have a light smooth smoke that dissipates easily after they have been extinguished. Not all incense sticks are equal, the smoke from all I have used appears grey to the eye. After some colour saturation is applied to the image all will appear to have colour and some will display multiple colours intertwined. This is due to the construction of the stick having different elements that produce different colours in the smoke. The picture used as a banner right at the top of this page is from an incense stick that presents (after saturation) different colours in the smoke. This picture has had only global edits to the colour, no local edits were necessary. It was not until 2010 that I realised such sticks existed and now I have a choice between monochrome and duotone smoke to work with. Speak to your local incense specialist retailer and ask them which sticks are best for producing smoke, they might know just the right product. By the way, I did try garden incense sticks thinking they would be bigger and produce more dense smoke; they were and they did. It was the only time I felt light headed from the effects of inhaling too much smoke, I recommend that garden incense sticks should only be used in the garden. I have also experimented with tobacco products (I did this for you, so that you wouldn't have to. Thank you Graham.) which keep burning, produce a good quality smooth smoke, monochrome blue in colour, but are too expensive and no better than ordinary incense sticks. I tried paper, specifically the absorbent kitchen towel and also toilet roll. I took a couple of sheets and twisted them into a stick that would stand upright. Always at hand and virtually no cost the paper smouldered well without going out, it produced quit a lot of dense single colour grey/blue smoke. Interestingly the twist in the paper was reflected in the smoke, the lowest part of the plume exhibited a twist rather than the smooth laminar flow we would normally see. Unfortunately there is a downside, paper produces a lot of dirty ash. It also has a bad smell, not so much whilst burning but after it has been snuffed out. I left the remains of a partially burned paper roll in the studio overnight, and it took days to purge the room of that burnt paper smell. Manipulating the smoke. In perfectly still air the smoke will rise in a straight column driven by the heat from the smouldering source. After a certain height there will be slight turbulence and then the smoke will accumulate in a cloud. Try to avoid getting the cloud in the picture, it spoils focus and contrast. Unless breathing and heartbeat stop it is unlikely that this will happen whilst photographing smoke. There will be some air movement and you should see shapes forming in the smoke. To vary the patterns try wafting or blowing near the smoke. Another way to change the shape of the smoke is to introduce a small obstruction to the path of the smoke, I have used spoons, a cheese grater, and other sundry items, each seems to have its own profile in the way the smoke is affected. By using obstructions the drag on the smoke seems to slow down the turbulence making the smoke move lazily. To slow down the smoke even more introduce an obstruction like a funnel at an angle that will move the smoke column so that it is no longer directly above the heat. To speed up the smoke (and raise that cloud I mentioned earlier) add more heat. This can be done by placing 3 or 4 lit candles (I use tea lights) around the source of the smoke at a distance of a few inches. Focus. Out of focus smoke in smoke art holds very few charms for me. Where smoke is concerned, in or out of focus is a subjective assessment that we all have to make with each picture. Sharpening tools are getting better year by year but there isn’t much I can do with a mainly out of focus image except delete it or heavily crop it into focus. To auto focus or to prefocus on the smoke is a contentious issue, there is something to say in favour off both methods. Just experiment and see what works best for you. I am firmly in the prefocus camp, I focus on where I expect the smoke to be. I usually stand away from the viewfinder to better see the shapes forming. It is a lot easier to react to a developing shape if you can see the whole scene; if you wait to see the perfect smoke shape in the viewfinder the chances are that you’ll be too late. It is best to use a remote release for this. If you are having trouble with focus it may be because from behind the camera you can’t judge exactly where the smoke is in relation to distance from the lens. Try this, before lighting the incense but after your camera position, focal length and aperture have been decided. Set some markers in front and behind the incense, focus on the incense and fire a couple of test shots. Then assess where the area of acceptable focus lies. Leave one marker for the nearest point of acceptable focus, and one for the furthest. Now by using a remote release you can stand alongside the smoke and only shoot when you see a plume within these markers. Checking the exposure. Take just a few shots to start with; this is the time to check the exposure. Checking the histogram at this stage won’t help unless you already have experience of shooting smoke. There is no bell curve with smoke photography, these are not shots in the park, they are shots in the dark. I recommend that you process a few shots at this stage to ensure you have all the settings right. Adjust the exposure so that the brightest part of the smoke is almost white. Over exposure will lose some detail and the smoke will look blocky and unattractive. Under exposure will result in lack of contrast and the smoke will blend too well with the background. Practise, and lots of it, is required to get all the exposure settings right. The trouble with image size. Smoke photography is a trial and error business, with the number of usable images representing a very small percentage of those taken. All I want is a beautiful shape, beautifully focused, and beautifully exposed. If all the basics are right this will happen from time to time, but to have it fill the frame as well appears to be asking too much. This has seldom, if ever, happened for me. It doesn’t matter what the focal length of the lens is, you are always going to struggle with depth of field if you are photographing smoke in it’s turbulent phase. More precisely depth of field and acceptable image size in pixels. If you stand far enough back you can get the whole room in focus but the number of pixels devoted to the smoke will be tiny. I did innumerable trials using different lenses and focal lengths before I realised that it just doesn’t make any real difference. I won’t say don’t waste your time, research is always good, just don’t be surprised if you never find that magic focal length. If you are using one of those new 80 megapixel digital backs you are going to get more usable smoke pixels, but if your camera is more modestly endowed in that department you will have to resign yourself to relying on luck to get that really large image. The alternative is to build your smoke art from multiple exposures, that way there is no limit to the size of file you can create. Post processing. It is not my intention to delve into the black arts of Photoshop, we all have our own levels of expertise, favourite techniques etc. Most of what you have learnt, or will learn about image enhancement can be applied to smoke pictures. This section is about principals rather than recipes. Over time I must have used about every blending mode, third party plugin, and technique that I have available to me, but in the end simple is usually best. After the initial selection process, which takes the longest time, I start to work on an image. In the second phase of the selection process I open the image in a RAW processor, I am using Adobe Lightroom at the moment. If you are shooting in JPEG then use the image editor of your choice but RAW would be better because of the wide latitude afforded by that file format. • Pump up the saturation not to maximum, if saturation is too high there is a risk of introducing noise. • Tweak the colour temperature, again watch out for added noise if this is taken too far. • Play with exposure, and the black point. • Look at the cropping possibilities. • Throw out all but the best. Cleanup. With the remainder it is time for the cleanup. Paint all the almost blacks in the background with RGB 0,0,0. Be careful not to swipe away any usable smoke. Use a hard brush if you are painting up close to a hard edge and a soft brush near soft edges. Spot the picture for sensor dust, and environmental dust, you were after all just before shooting, wafting dust around the studio. In the same way that dust appears, so do black holes, little patches where the smoke is less dense than it’s surrounding area, spot healing will do the trick. When you think you have dealt with all the spots invert the image and deal with the ones you have missed. Having now seen the smoke both on a black and a white background you will know which is more appealing. Applying colour. There are loads of ways to apply colour to the smoke I suggest you dabble, and experiment. I have tried lots of methods, from soft selections with colour balance and hue/saturation to gradient layers with the blend mode set to colour. There is no limits to, and certainly no correct way of applying colour. Sharpening or not. I would recommend that any sharpening is applied sparingly, to see artefacts on the edge of the smoke is not attractive. In some images I have gone the other way and applied a very small amount of edge sharpening combined with surface blur to smooth out the non edge areas of smoke. Try anything. Conclusion. I have found creating smoke art at times both frustrating and very satisfying. Some people manage to get things right from the word go and others have had to struggle to produce decent pictures. I hope that, if you intend to have a go at creating coloured smoke pictures, these notes help to put you straight into the first group. Have fun. I would love to have comments from anyone who feels that they can add to this article, or even disagree with what I have said for that matter. If you have experience of smoke photography and have something to say that might help others then please leave a comment. I should be particularly grateful to hear from anyone who has experience of different sources of smoke, especially if they exhibit multiple colours or pass on other distinctive qualities to the smoke, like the twist from twisted paper. For more smoke photographs see the Smoke art collection or the Smoke wheels collection Thanks, Graham.
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