Especially in underwater macro photography, it becomes challenging sometimes to get your subject separated from your background. You can try and achieve it shooting big aperture and shallow depth of field, another technique is to “snoot” your subject.
A snoot is a “light shaping device” which allows the photographer to reduce the beam of the light source and therefore gain more control over the exposure of your image. There is a whole bunch of different snoots now on the market: the RETRA snoot is probably the most sophisticated but also expensive option, 10bar offers a cheaper version including a laser or you can go for a DIY version. My first attempts with the snoot technique were actually done with the RGBlue video light and snoot kit.
Working with the snoot technique takes a lot of patience and a bit of practice. The results however are rewarding and add that little creative twist to your images. It can also reduce backscatter and create unique effects by directing the light.
I would highly recommend dedicating a dive to practice just the snoot technique. You will have to mount the snoot onto your strobes and putting it on, taking it off, putting it back on again can be quite annoying! Also, you want to shoot with only one strobe to start with. So get rid of all the extra drag and bring only the strobe with the snoot attached. You are looking for calm and easy conditions, ideally a bit of overcast and less sun to not overpower your focus light or laser.
Picking the right subject is crucial as well. You do not want to start your first snoot experience with a moving subject like an Mimic Octopus or Pygmy Seahorse in an environment where you cannot steady yourself. As usual, Nudibranchs or Frogfish are perfect to experiment with the snoot technique.
What is nice about the 10bar snoot is that you can choose the diameter of the snoot depending on the size of your subject. Since you want to exclude as much light as possible, you will have to practice which diameter for which size of subject but you will probably get a feel for that quite quickly. The bigger challenge is then to direct the snoot and have it at the right distance from the subject.
I usually find myself a rock of similar size of whatever I’d like to snoot. I then roughly choose my camera settings and focus distance, pretending to shoot that rock. Then I adjust the position of my strobe with attached snoot and do the fine tuning on the actual subject.
This is when the integrated laser in the 10bar snoot comes handy. It gives you a rough idea where the snoot is pointing at and where the strobe will output light. Alternatively, you can use the focus light or your strobe of course which gives you a good indication where
That is also why my first tries with the snoot were with a constant video light – that way you can see the output of light and where it is pointing at straight away. The only problem is that the output of a video light isn’t quite strong enough.
When it comes to camera settings, I use fast shutter like 1/200 and small aperture around f/16. You will have to put your strobes on high power to get your image properly illuminated. Don’t worry too much if you cannot get the exposure 100% right in camera, focus more on the positioning of the snoot – the rest can be done by playing with the blacks in Lightroom.
So if you’re looking for a new challenge and another way to shoot more creative images underwater, try the snoot technique. And like anything after a bit of practice, it becomes easy 🙂